Signal generation method and signal generation device
Abstract
The invention describes a transmission method that simultaneously transmits a first modulated signal and a second modulated signal at a common frequency performs precoding on both signals using a fixed precoding matrix and regularly changes the phase of at least one of the signals, thus improving the quality of the data signal received at a receiving device.

Term
6.3 yearsleft in the term
Expires 23 January 2033.
- Priority
- Filed
- Granted
- Today
- Expires
4 claims: 4 independent, 0 dependent
- 1REIVINDICACIONES Habiéndose descrito la invención como antecede, se reclama como propiedad lo contenido en las siguientes reivindicaciones:1. Un método de transmisión caracterizado porque comprende: llevar a cabo codificación para generar bloques codificados hechos de una pluralidad de bits al utilizar un esquema de codificación de bloque de corrección de error predeterminado;llevar a cabo generación de señal de transmisión para generar, para cada una de una pluralidad de ranuras, una primera señal de transmisión zl y una segunda señal de transmisión z2 desde los bloque codificados;y transmitir la primera señal de transmisión zl desde una primera antena de una primera estación base en un primer periodo a una primera frecuencia, y la segunda señal de transmisión z2 desde una segunda antena de una segunda estación base en el primer periodo de la primera frecuencia, la generación de señal de transmisión incluye: generar, para cada una de la pluralidad de ranuras, una primera señal modulada si y una segunda señal modulada s2 desde cada uno de los bloques codificados;con respecto a la primera señal modulada si y a la 414 IMPI INSTITUTO MEXICANO DE LA PROPIEDAD INDUSTRIAL segunda señal modulada s2, aplicar pre-codificación expresada por una matriz fija F, la matriz F es expresada como: F - 1 a x 7« 2 +l e' 0 j en donde a representa un número real positivo que excluye 0;y con respecto al menos a una de la primera señal modulada si y a la segunda señal modulada s2, llevar a cabo un cambio de fase mientras que se varía regularmente un esquema de cambio de fase para cada una de la pluralidad de ranuras, en la codificación, un primer bloque codificado y un segundo bloque codificado diferente del primer bloque codificado que se genera como los bloques codificados, y un esquema de cambio de fase seleccionado para la primera ranura en la generación de señal de transmisión dirigida para el primer bloque codificado que es el mismo que un esquema de cambio de fase seleccionado para la primera ranura en la generación de señal de transmisión dirigida para el segundo bloque codificado.
- 2Un aparato de transmisión caracterizado porque comprende:un codificador que lleva a cabo codificación para generar bloques codificados hechos de una pluralidad de bits 415 IMPI INSTITUTO MEXICANO DE LA PROPIEDAD INDUSTRIAL al utilizar un esquema de codificación de bloque de corrección de error predeterminado;un generador de señal de transmisión que lleva a cabo generación de señal de transmisión para generar, para cada una de una pluralidad de ranuras, una primera señal de transmisión zl y una segunda señal de transmisión z2 desde los bloques codificados;un primer transmisor que transmite la primera señal de transmisión zl desde una primera antena de una primera estación base en un primer periodo a una primera frecuencia;y un segundo transmisor que transmite la segunda señal de transmisión z2 desde una segunda antena de una segunda estación base en un primer periodo a la primera frecuencia, el generador de señal de transmisión incluye: un generador de señal modulada que genera, para cada una de la pluralidad de ranuras, generadora una primera señal modulada si y una segunda señal modulada s2 desde cada uno de los bloques codificados;un pre-codificador que aplica precodificación expresada por una matriz fija F con respecto a la primera señal modulada si y la segunda señal modulada s2, la matriz F es expresada como: _ 1 í e ;0 axe JiT •Ja 2 +l[axe^ e y0 j 416 IMPI INSTITUTO MEXICANO DE LA PROPIEDAD INDUSTRIAL en donde a representa un número real positivo que excluye 0;y un cambiador de fase que lleva a cabo un cambio de fase mientras que se varía regularmente un esquema de cambio de fase para cada una de la pluralidad de ranuras con respecto al menos a una de la primera señal modulada si y a la segunda señal modulada s2, el codificador genera, como los bloques codificados, un primer bloque codificado y un segundo bloque codificado diferente del primer bloque codificado, y un esquema de cambio de fase seleccionado para la primera ranura en la generación de señal de transmisión mediante el generador de señal de transmisión dirigido para el primer bloque codificado que es el mismo que un esquema de cambio de fase seleccionado para la primera ranura en la generación de señal de transmisión dirigida para el segundo bloque codificado.
- 3Un método de recepción caracterizado porque comprende:adquirir una señal de recepción obtenida al recibir una primera señal de transmisión zl transmitida desde una primera antena de una primera estación base en un primer periodo a una primera frecuencia y una segunda señal transmisión z2 transmitida desde una segunda antena de una segunda estación base en el primer periodo a la primera 417 IMPI INSTITUTO MEXICANO DE LA PROPIEDAD INDUSTRIAL frecuencia, la primera señal de transmisión zl y la segunda señal de transmisión z2 habiendo sido generadas por un proceso de generación predeterminado;y obtener datos de recepción al aplicar un proceso de demodulación que corresponda al proceso de generación predeterminado para la señal de recepción, el proceso de generación predeterminado es un proceso para llevar a cabo generación de señal de transmisión para generar, para cada una de una pluralidad de ranuras, la primera señal de transmisión zl y la segunda señal de transmisión z2 a partir de cada uno de los bloques codificados que ha sido generado al llevar a cabo codificación utilizando un esquema de codificación de corrección de error predeterminado y hecho de una pluralidad de bits, y la generación de señal de transmisión incluye: generar, para cada una de la pluralidad de ranuras, una primera señal modulada si y una segunda señal modulada s2 a partir de cada uno de los bloques codificados;con respecto a la primera señal modulada si y a la segunda señal modulada s2, aplicar pre-codificación expresada por una matriz fija F, la matriz F es expresada como: _ 1 e J0 Ja 2 +l\axe J0 e J0 ;418 IMPI INSTITUTO MEXICANO DE LA PROPIEDAD INDUSTRIAL en donde a representa un número real positivo que excluye 0;y con respecto al menos a una de la primera señal modulada si y a la segunda señal modulada s2, llevar a cabo un cambio de fase mientras que se varía regularmente un esquema de cambio de fase para cada una de la pluralidad de ranuras, en la codificación, un primer bloque codificado y un segundo bloque codificado diferente del primer bloque codificado que se genera como los bloques codificados, y un esquema de cambio de fase seleccionado para la primera ranura en la generación de señal de transmisión dirigida para el primer bloque codificado que es el mismo que un esquema de cambio de fase seleccionado para la primera ranura en la generación de señal de transmisión dirigida para el segundo bloque codificado.
- 4Un aparato de recepción caracterizado porque comprende:un adquisidor que adquiere una señal de recepción obtenida al recibir una primera señal de transmisión zl transmitida desde una primera antena de una primera estación base en un primer periodo a una primera frecuencia y una segunda señal de transmisión z2 transmitida desde una segunda antena de una segunda estación base en el primer periodo a la primera frecuencia, la primera señal de transmisión zl y la 419 IMPI INSTITUTO MEXICANO DE LA PROPIEDAD INDUSTRIAL segunda señal de transmisión z2 habiendo sido generadas por un proceso de generación predeterminado;y un desmodulador que obtiene datos de recepción al aplicar un proceso de demodulación que corresponde al proceso de generación predeterminado para la señal de recepción, el proceso de generación predeterminado es un proceso para llevar a cabo generación de señal de transmisión para generar, para cada una de la pluralidad de ranuras, la primera señal de transmisión zl y la segunda señal de transmisión z2 a partir de cada uno de los bloques codificados que ha sido generado al llevar a cabo codificación al utilizar un esquema de codificación de corrección de error predeterminado y hecho de una pluralidad de bits, y la generación de señal de transmisión incluye: generar, para cada una de la pluralidad de ranuras, una primera señal modulada si y una segunda señal modulada s2 a partir década uno de los bloques codificados;con respecto a la primera señal modulada si y a la segunda señal modulada s2, aplicar pre-codificación expresada por una matriz fija F, la matriz F es expresada como: - i í e 0 a x eJ,T Ja*Vl\a*e J0 e J * / en donde a representa un número real positivo que 420 IMPI INSTITUTO MEXICANO DE LA PROPIEDAD INDUSTRIAL excluye 0;y con respecto al menos a una de la primera señal modulada si y a la segunda señal modulada s2, llevar a cabo un cambio de fase mientras que se varía regularmente un 5 esquema de cambio de fase para cada una de la pluralidad de ranuras, en la codificación, un primer bloque codificado y un segundo bloque codificado diferente del primer bloque codificado que se genera como los bloques codificados, y 10 un esquema de cambio de fase seleccionado para la primera ranura en la generación de señal de transmisión dirigida para el primer bloque codificado que es el mismo que un esquema de cambio de fase seleccionado para la primera ranura en la generación de señal de transmisión dirigida para 15 el segundo bloque codificado.
Independent claims4
2,592 paragraphs in 565 sections, as filed
SIGNAL GENERATION METHOD AND SIGNAL GENERATION APPARATUS
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
field of invention
The present invention relates to a transmitting device and a receiving device for communication using multiple antennas.
Background of the Invention
A MIMO (multiple input, multiple output) system is an example of a conventional communication system that uses multiple antennas. In multi-antenna communication, of which the MIMO system is representative, each of multiple transmission signals is modulated, and each modulated signal is transmitted at the same time from a different antenna in order to increase the transmission speed of the signals. data.
Figure 23 illustrates an exemplary configuration of a transmit and receive device having two transmit antennas and two receive antennas, and using two transmit modulated signals (transmit currents). In the transmission apparatus, the encoded data is interpolated, the interpolated data is modulated, and frequency conversion and the like are performed to generate transmission signals, and the transmission signals are transmitted from the antennas. In that case, the method for simultaneously transmitting different modulated signals from
I laughed. No.: 261287
<img file="MX385274B_D0001.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY different transmission antennas at the same time and on the same frequency is the spatial multiplexing MIMO system.
In this context, Patent Literature 1 suggests the use of a transmission device provided with a different interpolation pattern for each transmission antenna. That is, the transmission device of Figure 23 must use two differentiated interpolation patterns performed by two interpolators (n<sub>a</sub> and nb). As far as the receiving device is concerned, Non-Patent Literature 1 and Non-Patent Literature 2 describe how to improve the reception quality by iteratively using software values for the detection scheme (by the MIMO detector in Fig. 2. 3).
As it happens, models of real propagation environments in wireless communications include NLOS (non-line-of-sight) models, of which a Rayleigh fading environment is representative, and LOS (with line of sight), of which a Rician fading environment is representative. When the transmitting device transmits a single modulated signal, and the receiving device performs maximum ratio combining on the signals received by multiple antennas, and then demodulates and decodes the resulting signals, excellent reception quality can be achieved in a LOS environment, in particular, in an environment where the Rician factor is large. The Rician factor represents the power received from direct waves relative to
<img file="MX385274B_D0002.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY with the power received from the scattered waves. However, depending on the transmission system (for example, a spatial multiplexing MIMO system), a problem occurs in that the reception quality deteriorates when the Rician factor increases (see Non-Patent Literature 3).
Figures 24A and 24B illustrate an example of the simulation results of the Bit Error Rate (BER) characteristics (vertical axis: BER, horizontal axis: SNR (Signal to Noise Ratio) for data encoded with LDPC (Base Density Parity Check) codes and transmitted by a 2x2 spatial multiplexing MIMO system (two transmit antennas, two receive antennas) in a Rayleigh fading environment and in a Rician fading environment with Rician factors of K = 3, 10 and 16 dB. Figure 24A gives log-likelihood ratio BER characteristics based on Max-Log approximation (Max-log APP) without iterative detection (see Non-Patent Literature 1 and Non-Patent Literature 2), while Figure 24B gives the BER Max-Log APP feature with iterative detection (see Non-Patent Literature 1 and Non-Patent Literature 2) (number of iterations: five). Figures 24A and 24B clearly indicate that, regardless of whether iterative detection is performed or not, the reception quality degrades in the spatial multiplexing MIMO system when the Rician factor increases. Therefore, the problem of quality degradation
<img file="MX385274B_D0003.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY reception when stabilizing the propagation environment in the spatial multiplexing MIMO system, which does not occur in a conventional system of single modulation signals, is exclusive to the spatial multiplexing MIMO system.
Broadcast or multicast communication is a service applied to various propagation environments. The radio wave propagation environment between the broadcasting station and the receiving devices belonging to the users is often a LOS environment. When using a spatial multiplexing MIMO system with the above problem for broadcast or multicast communication, a situation may arise where the received power of the electric field at the receiving apparatus is high, but the quality degradation of reception makes it impossible to receive the service. In other words, in order to use a spatial multiplexing MIMO system in broadcast or multicast communication, both in an NLOS environment and in a LOS environment, there is a desire to develop a MIMO transmission system that offers a certain degree of reception quality.
Non-Patent Literature 8 describes a method for selecting a codebook to be used in precoding (i.e., a precoding matrix, also called a weighting matrix for precoding) based on feedback information from a partner. Communication. Non-Patent Literature 8 does not describe at all, however,
<img file="MX385274B_D0004.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY a method for precoding in an environment where feedback information from the communication partner cannot be acquired, as is the case in the preceding broadcast or multicast communication.
On the other hand, Non-Patent Literature 4 describes a method for changing the precoding matrix over time. This scheme is applicable when no feedback information is available. Non-patent Literature 4 describes the use of a unit matrix as the matrix for precoding and changing the unit matrix 10 randomly, but does not describe at all a method applicable to the degradation of reception quality in the environment THE previously described. Non-Patent Literature 4 simply mentions random jumps between precoding matrices. Obviously, the Non-patent Literature 4 makes no mention at all of a precoding method or a structure of a precoding matrix, to remedy the degradation of reception quality in a LOS environment.
List of mentions
patent literature
Patent literature 1
Publication of the International Patent Application
No. WO2005/050885
Non-patent literature
Non-Patent Literature 1
Achieving near-capacity on a multiple-antenna channel IEEE Transaction on Communications, vol.51, no. 3,
<img file="MX385274B_D0005.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY pages 389-399, March 2003.
Non-Patent Literature 2
Performance analysis and design optimization of LDPC-coded MIMO OFDM systems IEEE Trans. Signal Processing, vol.52, no.2, pages 348-361, Feb. 2004.
Non-Patent Literature 3
BER performance evaluation in 2x2 MIMO spatial multiplexing systems under Rician fading channels IBICE Trans. Fundamétale, vol.E91-A, no.10, pages 2798-2807, Oct. 2008.
Non-Patent Literature 4
Turbo space-time codes with time varying linear transformations IEEE Trans. Wireless Communications, vol.6, no.2, pages 486-493, Feb. 2007.
Non-Patent Literature 5
Likelihood function for QR-MLD suitable for soft-decision turbo decoding and its performance IEICE Trans. Commun., vol.E88-B, no.l, pages 47-57, Jan. 2004.
Non-Patent Literature 6
A tutorial on 'Parallel concatenated (Turbo) coding' , 'Turbo (iterative) decoding' and related topics IEICE, Technical Report IT98-51.
Non-Patent Literature 7
Advanced signal processing for PLCs: Wavelet-OFDM Proc. of IEEE International symposium on ISPLC 2008, pages 187-192, 2008.
<img file="MX385274B_D0006.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Non-Patent Literature 8
DJ Lovey R. W. HeathJr., Limited feedback unitary precoding for spatial multiplexing systems IEEE Trans. Inf. Theory, vol.51, no.8, pages 2967-1976, Aug. 2005.
Non-Patent Literature 9
DVB Document A122, Framing structure, channel coding and modulation for a second generation digital terrestrial television broadcasting system (DVB-T2), Jun. 2008.
Non-Patent Literature 10
L. Vangelista, N. Benvenuto, and S. Tomasin Key technologies for next-generation terrestrial digital television standard DVB-T2, IEEE Commun. Magazine, vol.47, no.10, pages 146-153, Oct. 2009.
Non-Patent Literature 11
T. Ohgane, T. Nishimura, and Y. Ogawa, Application of space division multiplexing and those performance in a MIMO channel IEICE Trans. Commun., vo.88-B, no.5, pages 1843-1851, May 2005.
Non-Patent Literature 12
RG Gallager Low-density parity-check codes, IRE Trans. Inform Theory, IT-8, pages 21-28, 1962.
Non-Patent Literature 13
DJC Mackay, Good error-correcting codes based on very sparse matrices, IEEE Trans. Inform Theory, vol. 45, no. 2, pages 399-431, March 1999.
<img file="MX385274B_D0007.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Non-Patent Literature 14
ETSI EN 302 307, Second generation framing structure, channel coding and modulation systems for broadcasting, interactive Services, news gathering and other broadband satellite applications v.1.1.2, Jun. 2006.
Non-Patent Literature 15
Y.-L. Ueng, and C.-C. Cheng A fast-convergence decoding method and memory-efficient VLSI decoder architecture for irregular LDPC codes in the IEEE 802.16e standards IEEE VTC-2007 Fall, pages 1255-1259.
Non-Patent Literature 16
SM Alamouti Asimple transmit diversity technique for wireless Communications IEEE J. Select. Common Areas, vol. 16, no.8, pages 1451-1458, Oct 1998.
Non-Patent Literature 17
V. Tarokh, H. Jafrkhani, and AR Calderbank Space-time block coding for wireless Communications: Performance results IEEE J. Select. Common Areas , vol. 17, no. 3, no.3, pages 451-460, March 1999.
Brief Description of the Invention
technical problem
It is an object of the present invention to provide a MIMO system that improves reception quality in a LOS environment.
Solution to the problem
The present invention provides a generation scheme
<img file="MX385274B_D0008.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL of signals to generate, from multiple baseband signals, multiple signals for transmission in a common frequency band and at a common date-time, comprising the steps of: generating M first coded blocks usable as a first set of bits and M second coded blocks usable as a second set of bits, using a predetermined block coding scheme for error correction, where M is a natural number; perform a phase shift on each of a first baseband signal si generated from the first set of bits and a second baseband signal s2 generated from the second set of bits, thus generating a post-phase shifted first baseband signal si' and a second post-phase shifted baseband signal s2', each of which includes M symbols; and applying the weighting to the first post-phase shifted baseband signal si' and to the second post-phase shifted baseband signal s2' in accordance with a predetermined matrix F, thereby generating the multiple signals for transmission on the common band frequency and the common date-time as a combination of M pairs of a first weighted signal zl and a second weighted signal z2, where the first weighted signal zl and the second weighted signal z2 satisfy the relationship: (zl, z2)<sup>T</sup> =F(if',s2')<sup>T</sup> and phase shifting is performed on the first baseband signal si and the second baseband signal s2 using a phase shift value sequentially selected from among N phase shift value candidates.
<img file="MX385274B_D0009.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Furthermore, the present invention provides a signal generation apparatus for generating, from multiple baseband signals, multiple signals for transmission in a common frequency band and at a common date-time, comprising: an encoder that generates M first coded blocks usable as a first set of bits and M second coded blocks usable as a second set of bits, using a predetermined block coding scheme for error correction, where M is a natural number; a phase shifter that performs a phase shift on each of a first baseband signal si generated from the first set of bits and a second baseband signal s2 generated from the second set of bits, thereby generating a first baseband signal with postphase shift si' and a second postphase shift baseband signal s2', each of which includes M symbols; and a weighting unit that applies the weight to the first post-phase shifted baseband signal si' and to the second post-phase shifted baseband signal s2' according to a predetermined matrix F, thereby generating the multiple signals for transmission in the common band frequency and common date-time as a combination of M pairs of a first weighted signal zl and a second weighted signal z2, where the first weighted signal zl and the second weighted signal z2 fulfill the relationship: (zl, z2)<sup>T</sup> = F(sl', s2 ')<sup>T</sup> and the phase shift is performed on the first baseband signal si and the second baseband signal s2 using a phase shift value
<img file="MX385274B_D0010.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY sequentially selected among N candidates of phase modification value.
Advantageous effects of the invention
In accordance with the foregoing structure, the present invention provides a signal generation scheme and signal generation apparatus that remedy reception quality degradation in a LOS environment, thus providing high quality service to LOS users during communication. broadcast or multicast.
Brief Description of the Figures
Figure 1 illustrates an example of a transmitting and receiving device in a spatial multiplexing MIMO system.
Figure 2 illustrates an exemplary frame configuration.
Figure 3 illustrates an example of a transmission device applying a phase shift scheme.
Figure 4 illustrates another example of a transmission device applying a phase shift scheme.
Figure 5 illustrates another exemplary frame configuration.
Figure 6 illustrates an exemplary phase shift scheme.
Figure 7 illustrates an exemplifying configuration of a receiving device.
<img file="MX385274B_D0011.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Figure 8 illustrates an exemplary configuration of a receiving device signal processor.
Figure 9 illustrates another exemplary configuration of a receiving device signal processor.
Figure 10 illustrates an iterative decoding scheme.
Figure 11 illustrates exemplary receiving conditions.
Figure 12 illustrates a further example of a transmission device applying a phase shift scheme.
Figure 13 illustrates yet another example of a transmission device applying a phase shift scheme.
Figures 14A and 14B illustrate a further exemplary frame configuration.
Figures 15A and 15B illustrate yet another exemplary frame configuration.
Figures 16A and 16B illustrate yet another exemplary frame configuration.
Figures 17A and 17B illustrate yet another exemplary frame configuration.
Figures 18A and 18B illustrate yet another exemplary frame configuration.
Figures 19A and 19B illustrate examples of a schematic
<img file="MX385274B_D0012.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY correlation.
Figures 20A and 20B illustrate further examples of a mapping scheme.
Figure 21 illustrates an exemplary configuration of a weighting unit.
Figure 22 illustrates an exemplary symbol rearrangement scheme.
Figure 23 illustrates another example of a transmitting and receiving device in a spatial multiplexing MIMO system.
Figures 24A and 24B illustrate exemplary BER characteristics.
Figure 25 illustrates another exemplary phase shift scheme.
Figure 26 illustrates yet another exemplary phase shift scheme.
Figure 27 illustrates a further exemplary phase shift scheme.
Figure 28 illustrates yet another exemplary phase shift scheme.
Figure 29 illustrates yet another exemplary phase shift scheme.
Figure 30 illustrates an exemplary symbol arrangement for a modulated signal that provides a high quality received signal.
<img file="MX385274B_D0013.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Figure 31 illustrates an exemplary frame configuration for a modulated signal that provides a high quality of received signal.
Figure 32 illustrates another exemplary symbol arrangement for a modulated signal that provides a high quality received signal.
Figure 33 illustrates yet another exemplary symbol arrangement for a modulated signal that provides a high quality received signal.
Figure 34 illustrates the variation in symbol numbers and intervals required per encoded block, when block codes are used.
Figure 35 illustrates the variation in numbers of symbols and intervals required per pair of coded blocks, when block codes are used.
Figure 36 illustrates an overall configuration of a digital broadcast system.
Figure 37 is a block diagram illustrating an exemplary receiver.
Figure 38 illustrates the multiplexed data configuration.
Figure 39 is a schematic diagram illustrating the multiplexing of stream-encoded data.
Figure 40 is a detailed diagram illustrating a video stream as contained in a sequence of packets
<img file="MX385274B_D0014.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
PES.
Fig. 41 is a structural diagram of TS packets and multiplexed data source packets.
Figure 42 illustrates the PMT data configuration.
Figure 43 illustrates the information as configured in the multiplexed data.
Figure 44 illustrates the configuration of the stream attribute information.
Figure 45 illustrates the configuration of a video display and audio output device.
Figure 46 illustrates an exemplary configuration of a communications system.
Figures 47A and 47B illustrate an exemplary symbol layout variant for a modulated signal that provides a high received signal quality.
Figures 48A and 48B illustrate another exemplary symbol arrangement variant for a modulated signal providing a high received signal quality.
Figures 49A and 49B illustrate yet another exemplary symbol arrangement variant for a modulated signal providing a high received signal quality.
Figures 50A and 50B illustrate yet another variant of the exemplary symbol arrangement for a modulated signal providing a high received signal quality.
Figure 51 illustrates a configuration
<img file="MX385274B_D0015.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY example of a transmission device.
Figure 52 illustrates another exemplary configuration of a transmission device.
Figure 53 illustrates a further exemplary configuration of a transmission device.
Fig. 54 illustrates yet another exemplary configuration of a transmission device.
Figure 55 illustrates a baseband signal changer.
Fig. 56 illustrates yet another exemplary configuration of a transmission device.
Figure 57 illustrates exemplary operations of a distributor.
Figure 58 illustrates more exemplifying operations of a distributor.
Figure 59 illustrates an exemplary communications system indicating the relationship between base stations and terminals.
Figure 60 illustrates an example of frequency assignment to transmission signals.
Figure 61 illustrates another example of frequency assignment to transmission signals.
Figure 62 illustrates an exemplary communications system indicating the relationship between a base station<sub>you</sub>repeaters and terminals.
<img file="MX385274B_D0016.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Figure 63 illustrates an example of frequency assignment to transmit signals relative to the base station.
Figure 64 illustrates an example of frequency assignment to transmit signals relative to repeaters.
Figure 65 illustrates an exemplary repeater receiver and transmitter configuration.
Figure 66 illustrates a signal data format used for transmission by the base station.
Figure 67 illustrates yet another exemplary configuration of a transmission device.
Figure 68 illustrates another baseband signal changer.
Figure 69 illustrates a weighting, baseband signal shift, and phase shift scheme.
Figure 70 illustrates an exemplary configuration of a transmission device using an OFDM scheme.
Figures 71A and 71B illustrate additional exemplary frame configurations.
Figure 72 illustrates the interval amounts and phase shift values corresponding to a modulation scheme.
Figure 73 further illustrates the amounts of
<img file="MX385274B_D0017.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY intervals and phase shift values corresponding to a modulation scheme.
Figure 74 illustrates the overall frame configuration of a signal transmitted by a broadcast station using DVB-T2.
Figure 75 illustrates two or more types of signals at the same date-time.
Fig. 76 illustrates yet another exemplary configuration of a transmission device.
Figure 77 illustrates an alternative exemplary frame configuration.
Figure 78 illustrates another alternative exemplary frame configuration.
Figure 79 illustrates a further alternative exemplary frame configuration.
θθ illustrates yet another alternative exemplary frame configuration.
Figure 81 illustrates yet another alternative exemplary frame configuration.
Figure 82 illustrates yet another alternative exemplary frame configuration.
Figure 83 illustrates yet another alternative exemplary frame configuration.
Figure 84 illustrates two or more additional types of signals at the same date-time.
Figure 85 illustrates a configuration
<img file="MX385274B_D0018.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY Alternative example of a transmission device.
Figure 86 illustrates an alternative exemplary θ3 configuration of a receiving device.
Figure 87 illustrates another alternative exemplary configuration of a receiving device.
Figure 88 illustrates yet another alternative exemplary configuration of a receiving device.
Figures 89A and 89B illustrate additional alternative exemplary frame configurations.
Figures 90A and 90B illustrate still further alternative exemplary frame configurations.
Figures 91A and 91B illustrate further alternative exemplary frame configurations.
Figures 92A and 92B illustrate even more alternative exemplary frame configurations.
Figures 93A and 93B illustrate still further alternative exemplary frame configurations.
Figure 94 illustrates an exemplary frame configuration used when space-time blocking codes are used.
Detailed description of the invention
The embodiments of the present invention are described below with reference to the accompanying figures.
<img file="MX385274B_D0019.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Modality 1
The following describes in detail a transmission scheme, a transmission device, a reception scheme and a reception device relevant to the present embodiment.
Before beginning the actual description, an outline of the transmission schemes and decoding schemes in a conventional spatial multiplexing MIMO system is provided. Figure 1 illustrates the structure of a spatial multiplexing MIMO system N<sub>c</sub>xN<sub>r</sub>. An information vector z is encoded and interpolated. The coded bit vector u = (ui, ... u<sub>nt</sub>) is obtained as the interpolation output. Here, Ui = (a, ... Ui<sub>M</sub>) (where M is the number of bits transmitted per symbol) . In the case of a transmission vector s = (Si, ... S<sub>nt</sub>) , a received signal Si = map(ui) is found for the transmit antenna #í. Normalizing the transmit power, this can be expressed as E{|yes|<sup>2</sup>} = I<sub>s</sub>/N<sub>you</sub> (where E<sub>s</sub> is the total energy per channel). The receiving vector y = (yi, ... y<sub>No.</sub>)<sup>T</sup> it is expressed in Mathematics 1 (formula 1), below.
[Math 1] (formula 1) y=(y^--,y<sub>N</sub>I =<sub>Λ7</sub> s + n JLJLAWr
<img file="MX385274B_D0020.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Here, H.<sub>nt</sub>NrθθI<sup>a</sup> channel matrix, n = (ni, ... n<sub>No.</sub>) is the noise vector and the average value of ni is zero for complex independent and identically distributed (iid) Gaussian noise of variance o<sup>2</sup>. Based on the relationship between the transmitted symbols input to a receiver and the received symbols, the probability distribution of the received vectors can be expressed as Math 2 (formula 2), below, for a multidimensional Gaussian distribution.
[Mathematics 2] (formula 2)
1/1 M p(y|“)=7----yw<sup>ex</sup>Py-Hs(u)
Here, we consider a receiver that performs iterative decoding. Such a receiver is illustrated in Figure 1 as consisting of an external software input/output decoder and a MIMO detector. The log-likelihood ratio vector (L-value) of Fig. 1 is given by Math 3 (formula 3) to Math 5 (formula 5), as follows.
[Mathematics 3] (formula 3)
L(u) = /
<img file="MX385274B_D0021.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
[Mathematics 4] (formula 4)
[Mathematics 5] (formula 5) (Iterative detection scheme)
The following describes the iterative detection of MIMO signals performed by the spatial multiplexing MIMO system N<sub>you</sub>xN<sub>r</sub>.
The log-likelihood ratio of Un» is defined by Math 6 (formula 6).
[Mathematics 6] (formula 6)
I y) = /«
Through the application of Bayes' theorem, Math 6 (Formula 6) can be expressed as Math 7 (Formula 7).
<img file="MX385274B_D0022.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
[Mathematics 7] (formula 7)
LO, I y) =<sub>+</sub>^1^=+<sup>1</sup>) <sup>P(</sup>u„=-V ^(ylw^-i) , p(<sub>or</sub> =+1) Συ pU I “WI uj
Συ p(y\^p^luj Q mn,-l
Note that u<sub>mn</sub>, <sub>±</sub>i = {u|umn = ±1}· By means of the approximation InZa, ~ max ln aj, Math 7 (formula 7) can be approximated as Math 8 (formula 8) . The symbol ~ is used here to mean approximation.
i [Mathematics 8] (formula 8)
L{u<sub>m</sub>„ | y) - ln<sup>+1)</sup> + max{ln<sub>p</sub>(<sub>Y</sub> | <sub>or</sub>) <sub>+</sub> p(<sub>or</sub> | )} = <sup>umn</sup>>^
- max {ln p(y | u) + P(u |<sub>mmm</sub>„)}
Ufnn,— i
In Math 8 (formulas), P(u|umn) γ1ηΡ(ν|υ^) can be expressed as follows.
<img file="MX385274B_D0023.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
[Math 9] (formula 9) p^\uj= IPW
<img file="MX385274B_D0024.tif" />
[Mathematics 10] (formula 10)
[Mathematics 11] (formula 11) lnP(uij) = -u¡jP(uij)-ln exp ·<sup>2</sup> l V + exp for
L(oops)
Note that the logarithmic probability of the given equation in Math 2 (formula 2) can be expressed as Math 12 (formula 12).
<img file="MX385274B_D0025.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
[Math 12] (formula 12) lnP(y | u) = -^y-Ιη^π --k<sup>2</sup> 2(7 y-Hs(u)
Therefore, given Math 7 (Formula 7) and Math 13 (Formula 13), the posterior L value for the MAP or APP (posterior probability!) can be expressed as follows.
[Mathematics 13] (formula 13)
Συ<sup>εχ</sup>ρ<
y-Hstuf+EMwJ ¿j y-Hs(u)
<img file="MX385274B_D0026.tif" />
This is hereinafter referred to as iterative APP decoding. Furthermore, given Math 8 (Formula 8) and Math 12 (Formula 12), the posterior L value for the Max-log APP can be expressed as follows.
[Mathematics 14] (formula 14)
Uu™ I y) = miM®. y> Mu))}<sup>vvmn</sup> Umn,+\ max{'P(u,y,L(u))}
<img file="MX385274B_D0027.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
[Mathematics 15] (formula 15)
Y(u,y,¿(u)) = --fy—Hs(u)<sup>2</sup> +X<sup>Zn/5</sup>U) 2cr v
This is hereafter called iterative Max-log APP decoding. By itself, the external information required by the iterative decoding system can be obtained by subtracting the previous input from Math 13 (Formula 13) or Math 14 (Formula 14).
system model
Figure 23 illustrates the basic configuration of a system related to the following explanations. The illustrated system is a 2x2 spatial multiplexing MIMO system that has an external decoder for each of two streams A and B. The two external decoders perform identical LDPC decoding (although the present description considers the example of a configuration where the external encoders use LDPC codes, the external encoders are not restricted to using LDPC as the error correcting codes). The example can also be performed using other error correcting codes, such as turbo codes, convolutional codes, or LDPC convolutional codes. Also, although the external encoders are now described as individually configured for each transmit antenna, no limitation is intended in that regard. A single can be used
<img file="MX385274B_D0028.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY external encoder for multiple transmission antennas or the number of external encoders may be greater than the number of transmission antennas. The system also has interpolators (n<sub>a</sub>, n<sub>b</sub>) for each of the currents A and B. Here, the modulation scheme is 2<sup>h</sup>-QAM (ie h bits are transmitted per symbol).
The receiver performs iterative detection (iterative APP (or Max-log APP) decoding) of the MIMO signals, as already described. LDPC codes are decoded using, for example, sum-product decoding.
Figure 2 illustrates the frame configuration and describes the order of the symbols after interpolation. here, (i<sub>at</sub>j<sub>a</sub>) and (ib.jb) can be expressed as follows.
[Mathematics 16] (formula 16)
<img file="MX385274B_D0029.tif" />
[Mathematics 17] (formula 17)
here, i<sub>a</sub> yi<sub>b</sub> represent the order of symbols after interpolation, j<sub>a</sub> yj<sub>b</sub> represent the bit position in the modulation scheme (where j<sub>a</sub>,jb = 1, - h) , n<sub>a</sub> yn<sub>b</sub>represent current interpolators A, B, and G<sup>a</sup>Yo<sub>a</sub>,j-<sub>a</sub> yn<sup>b</sup>ib,jb
<img file="MX385274B_D0030.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY represent the data order of streams A and B before interpolation. Note that Figure 2 illustrates a situation where i<sub>a</sub> = i<sub>b</sub>.
iterative decoding
The following describes in detail the sum-product decoding used to decode the LDPC codes and the iterative detection algorithm of MIMO signals, both used by the receiver.
Sum-product decoding
A two-dimensional MxN matrix H = {H<sub>mn</sub>} as the check matrix of the LDPC codes subject to decryption. In the case of the set [1,N] - {1, 2 ... N}, the partial sets A(m) and B(n) are defined as follows.
[Mathematics 18] (formula 18)
A(m) = {n: pf =1} mn<sup>J</sup>
[Mathematics 19] (formula 19)
B(n) = {m: fl -1} mn<sup>J</sup>
Here, A(m) means the set of column indices equal to 1 for row m of the check matrix H, while B(n) means the set of row indices equal to 1 for row n of the check matrix. check matrix H. The algorithm of the
<img file="MX385274B_D0031.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY sum-product decoding is as follows.
Step Al (Initialization): on all pairs (m,n) that satisfy H<sub>mn</sub> =1, the previous logarithmic ratio is established
Pmn = 1. Loop variable (number of iterations) l is set<sub>sum</sub> = 1, and the maximum number of loops l is set<sub>sum</sub>,<sub>raah</sub>x.
Step A-2 (Processing): For all pairs (m,n) that satisfy = 1 in the order m = 1, 2, ... M , update the log ratio of extrinsic value to<sub>mn</sub> using the following update formula.
[Mathematics 20] (formula 20)
OCmn
Π ^«(Α+AjWÍ Σ
[Math 21] (formula 21) sign(x) = x>0 x < 0
[Mathematics 22] (formula 22) /<sub>WBh</sub><sup>expw+1</sup> exp(r) -1 where f is the Gallager function. λ<sub>η</sub> it can then be computed as follows.
Step A-3 (Column operations) : on all pairs
<img file="MX385274B_D0032.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY (m,n) that meet H<sub>mn</sub> = 1 in the order n = 1, 2, ... N , the log ratio of extrinsic value is updated to<sub>mn</sub> using the following update formula.
[Mathematics 23] (formula 23)
<img file="MX385274B_D0033.tif" />
<img file="MX385274B_D0034.tif" />
Step A-4 (Calculation of log-likelihood ratio) : for ne [Ι,Ν] , the log-likelihood ratio L<sub>n</sub> is computed as follows.
[Mathematics 24] (formula 24) n
Step A-5 (Iteration count) : if l<sub>ITS</sub>m < l<sub>yes</sub>um,maxz then increase l<sub>suro</sub> and the process returns to step A-2. The sum-product decoding ends when l<sub>sum</sub> = he<sub>yes</sub>um,max
The above describes an iteration of the sum-product decoding operations. Subsequently, iterative detection of MIMO signals is performed. The variables m, η, β^, λ<sub>π</sub>, and L<sub>n</sub> used in the preceding explanation of the sum-product decoding operations are expressed as m<sub>a</sub>, n<sub>a</sub>, a<sup>a</sup>mana, p<sup>a</sup>Manaz Ána and L<sub>na</sub> for current A and as m<sub>b</sub>, n<sub>b</sub>, a<sup>b</sup>mbnbz β^ηΒζ Anb and Lnh for current B.
<img file="MX385274B_D0035.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Iterative detection of MIMO signals
The following describes the calculation of λ<sub>π</sub> for iterative detection of MIMO signals.
The following formula can be derived from Math 1 (formula 1).
[Math 25] (formula 25) yW = y<sub>2</sub>(t))<sup>T</sup>=H<sub>22</sub>Ú)s(0 + n(r)
Given the frame configuration illustrated in Fig.
2, the following functions are derivable from Math 16 (Formula 16) and Math 17 (Formula 17).
[Mathematics 26] (formula 26) n = Q Iba ώ &ia,ja
[Mathematics 27] (formula 27)
Ylb ^^ib,jb where n<sub>a</sub>,n<sub>b</sub>and [1,N] . For iteration k of the iterative detection of MIMO signals, the variables Á<sub>na</sub>, L<sub>na</sub>, A<sub>nb</sub> and Lnb are expressed as Xk,naz ^k.nai Xk<sub>>nb</sub> and Lk,<sub>nb</sub>.
Step Bl (Initial detection; k = 0)
For initial wave detection, Á<sub>O)na</sub> Already<sub>0</sub>,<sub>n</sub>b are calculated as follows.
For iterative APP decoding:
[Mathematics 28] (formula 28) y(zx)-H22G'x)<sup>s</sup>(<sup>or</sup>G'x)) *<sub>9</sub> «dy^)“H22(ix)s(u(f<sub>x</sub>))
For iterative Max-log APP decoding: [Mathematics 29] (formula 29)
4,<sup>=</sup>r Μ^ζΡ^ζΡ)}- {^(“Q\LyQ\))} ^Ο,ηχ,+Ι ©Ο,ην.-Ι
[Mathematics 30] (formula 30)
2σ y(z<sub>X</sub>)H22(z'x)<sup>s</sup>(<sup>or</sup>(zx)) where X = a,b. Next, the iteration count for iterative detection of MIMO signals is set to the minimum<sup>=</sup> 0 being the maximum iteration count
Step B-2 (Iterative Detection; Iteration k) : When the iteration count is k, Math 11 (formula 11), the
Math 13 (formula 13) to Math 15 (formula 15), the
<img file="MX385274B_D0036.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Math 16 (formula 16) and Math 17 (formula 17) can be expressed as Math 31 (formula 31) to Math 34 (formula 34) below. Note that (X,Y) = (a,b)(b,a).
For iterative APP decoding: [Mathematics 31] (formula 31) ^u.
Mu<sup>=</sup> J<sup>+ ln</sup> ' <sup>ex</sup>Q2
[ 2σ yGO-H<sub>2</sub>2(zx)s(u(/<sub>x</sub>))| ’
J* exp* ,'2σ y(z'x)<sup>_</sup>H22(l'x)S(u(ix))||
[Mathematics 32] (formula 32)
<img file="MX385274B_D0037.tif" />
/=1
<img file="MX385274B_D0038.tif" />
For iterative Max-log APP decoding: [Mathematics 33] (formula 33)
<img file="MX385274B_D0039.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
[Mathematics 34] (formula 34) í λ 1<sup>2</sup> y(i<sub>x</sub>)-H22G'x)<sup>s</sup>(<sup>or</sup>(zx))
Step B-3 {Iteration count and codeword estimation) If l<sub>mime</sub> < he<sub>ra</sub>Yo<sub>mo</sub>,max then increases Imimo and the process returns to step B-2. When I<sub>ra</sub>Yo<sub>mo</sub> = imi,max<sub>F</sub> θθ finds an estimated codeword, as follows.
[Mathematics 35] (formula 35) i Tt £ <0 ínúmo'Tlx where X = a,b.
Figure 3 shows an exemplary configuration of a transmission device 300 relevant to the present embodiment. An encoder 302A takes information (data) 301A and a framing signal 313 as input (which includes the error correction scheme, code rate, block length, and other information used by the encoder 302A in the error correction coding of the data, so that the scheme designated by the framing signal 313 is used. You can change the error correction scheme). According to the framing signal 313, the encoder 302A performs encoding of
<img file="MX385274B_D0040.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY error correction, such as convolutional encoding, LDPC encoding, turbo encoding or the like, and outputs the 303A encoded data.
An interpolator 304A takes the coded data 303A and the framing signal 313 as input, performs interpolation, that is, rearranges the order thereof, and then outputs the interpolated data 305A. (According to the frame setting signal 313, you can change the interpolation scheme).
A correlator 306A takes the interpolated data 305A and the framing signal 313 as input and performs modulation on them, such as QPSK (Quadrature Phase Shift Keying), 16-QAM (Quadrature Phase Shift Keying), 16-quadrature amplitude modulation) or 64-QAM (64-state quadrature amplitude paramodulation); it then outputs a baseband signal 307A. (According to the frame configuration signal 313, you can change the modulation scheme).
Figures 19A and 19B illustrate an example of a QPSK modulation correlation scheme for a baseband signal consisting of an I-phase component and a Q quadrature component in the IQ plane. For example, as shown in Fig. 19A, when the input data is 00, the output is 1=1.0, Q=1.0. Similarly, when input data with 01, the output is I = -1.0, Q = 1.0, etc. Figure 19B illustrates
<img file="MX385274B_D0041.tif" />
IMPI
MEXICAN INSTITUTE OF PROPERTY OR INDUSTRIAL an example of a QPSK modulation mapping scheme in the IQ plane that differs from Figure 19A in that the signal points in Figure 19A have been rotated around the origin to obtain the signal points in Figure 19B. Non-Patent Literature 9 and Non-Patent Literature 10 describe such a constellation rotation scheme. Alternatively, the cyclic Q delay described in Non-Patent Literature 9 and Non-Patent Literature 10 can also be adopted. An alternative example, other than Figures 19A and 19B, is shown in Figures 20A and 20B, which illustrate a signal point layout for 16-QAM in the IQ plane. The example of figure 2 0A corresponds to figure 19A, while that of figure 2 0B corresponds to figure 19B.
An encoder 302B takes information (data) 301B and framing signal 313 as input (which includes error correction scheme, coding rate, block length, and other information used by encoder 302A in encoding). error correction scheme of the data, so that the designated scheme is used by the framing signal 313. You can change the error correction scheme). According to the frame shaping signal 313, the encoder 302B performs error correction coding, such as convolutional coding, LDPC coding, turbo coding or the like, and outputs the 303B encoded data.
<img file="MX385274B_D0042.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
An interpolator 304B takes the coded data 303B and the framing signal 313 as input, performs interpolation, ie rearranges the order thereof, and outputs the interpolated data 305B. (According to the frame setting signal 313, you can change the interpolation scheme).
A correlator 306B takes the interpolated data 305B and the framing signal 313 as input and performs modulation on them, such as QPSK, 16-QAM or 64-QAM, then outputs a baseband signal 307B. (According to the frame configuration signal 313, you can change the modulation scheme).
An information generator for signal processing schemes 314 takes the framing signal 313 as input and therefore outputs the processing scheme information 315. The signal processing scheme information 315 designates the array of fixed precoding to be used and includes information about the pattern of phase changes used to change the phase.
A weighting unit 308A takes the baseband signal 3 07A, the baseband signal 3 07B, and the signal processing scheme information 315 as input, and, according to the signal processing scheme information 315, performs weighting. weighting on baseband signals 307A and 307B, then outputs a 3-weighted signal 09A. The Weighting Scheme
<img file="MX385274B_D0043.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY is described in detail below.
A wireless unit 310A takes the 3-weighted signal 09A as input and performs processing such as quadrature modulation, band limiting, frequency conversion, amplification, etc., then outputs the transmission signal 311A. An antenna 312A then outputs the transmission signal 311A as radio waves.
A weighting unit 3 08B takes the baseband signal 3 07A, the baseband signal 3 07B and the signal processing scheme information 315 as input and, according to the signal processing scheme information 315, performs weighting on baseband signals 307A and 307B, then outputting weighted signal 316B.
Figure 21 illustrates the configuration of the weighting units 3 08A and 3 08B. The area in Figure 21 surrounded by dashed lines represents one of the weight units. Baseband signal 307A is multiplied by wll to get wll-sl(t) and multiplied by w21 to get w21 · si (t) . Similarly, baseband signal 307B is multiplied by wl2 to get wl2 · s2 (t) and is multiplied by w22 to get w22 · s2 (t). Then zl (t) =wll'sl(t) + wl2-s2(t) and z2(t) = w21 si (t) + w22 s22(t) are obtained. Here, as already explained, if (t) and s2(t) are the baseband signals modulated according to a modulation scheme such as BPSK (Binary Phase Shift Keying), QPSK, 8-PSK (Binary Phase Shift Keying), phase shift of
<img file="MX385274B_D0044.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY symbols), 16-QAM, 32-QAM (quadrature amplitude modulation in 32 subchannels), 64-QAM, 256-QAM 16-APSK (16 symbol phase shift keying), etc.
Both weighting units perform weighting using a fixed precoding matrix. The precoding matrix uses, for example, the Math 36 (Formula 36) scheme and satisfies the conditions of Math 37 (Formula 37) or Math 38 (Formula 38), all of which are set forth below. However, this is just an example. The value of a is not restricted to Math 37 (Formula 37) and Math 38 (Formula 38) and can assume other values, for example a = 1.
Here, the precoding matrix is:
[Math 36] (formula 36) ^wll<sub>k</sub>w21
<img file="MX385274B_D0045.tif" />
In Mathematics 36 (formula 36) above, o¿ can be given by:
[Mathematics 37] (formula 37)
<img file="MX385274B_D0046.tif" />
Alternatively, in Math 36 (formula 36)
<img file="MX385274B_D0047.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY precedent, a can be given by:
[Mathematics 38] (formula 38)
<img file="MX385274B_D0048.tif" />
The precoding matrix is not restricted to that of Math 36 (formula 36), but can also be as indicated by Math 39 (formula 39). [Mathematics 39] (formula 39)<sup>λ</sup>η41 wl2^ (a ^νν21 w22 J d)
In Mathematics 39 (formula 39), let a = Ae<sup>j511</sup>, b = Be^<sup>612</sup>, c = Ce<sup>j521</sup> yd = From<sup>j622</sup>. Also, one of a, b, c and d' can be zero. For example, the following configurations are possible: (1) a can be zero as long as b, c, and d are nonzero, (2) b can be zero as long as a, c, and d are nonzero, (3) c can be zero as long as a, b, and d are nonzero, or (4) d can be zero as long as a, b, and c are nonzero.
When any of the modulation scheme, error correction codes and coding rate thereof changes, the precoding matrix can also be set, changed and fixed for use.
A 317B phase shifter takes the 316B weighted signal
<img file="MX385274B_D0049.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL and signal processing scheme information 315 as input, then regularly change the phase of signal 316B to output it. This regular change is a phase change performed according to a predetermined phase change pattern having a predetermined period (cycle) (for example, all n symbols (where n is an integer, n 1) or in a predetermined interval) . The details of the phase shift pattern are explained below in Mode 4.
The wireless unit 310B takes the post-phase shift signal 309B as input and performs processing such as quadrature modulation, band limiting, frequency conversion, amplification, etc. , then outputs the transmission signal 311B. Antenna 312B then outputs transmission signal 311B as radio waves.
Figure 4 illustrates an exemplary configuration of a transmission device 400 that differs from that of Figure 3. The points of difference between Figure 4 and Figure 3 are described below.
An encoder 402 takes the information (data) 401 and the framing signal 313 as input, and, according to the framing signal 313 , performs error correction coding and outputs the coded data 402.
A distributor 404 takes encoded data 403 as input, performs distribution thereof, and outputs data 405A and data 405B. Although Figure 4 illustrates only
<img file="MX385274B_D0050.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY encoder, the number of encoders is not limited to it. The present invention can also be implemented using m encoders (where m is an integer, m 1) such that the distributor divides the encrypted data created by each encoder into two groups for distribution.
Figure 5 illustrates an example of a time domain frame configuration for a transmission device according to the present embodiment. The 500_l token is to notify the receiving device about the transmission scheme. For example, symbol 500_l conveys information such as the error correction scheme used to transmit the data symbols, the code rate thereof, and the modulation scheme used to transmit the data symbols.
Symbol 501_l is for estimating the channel jitter of the modulated signal zl(t) (where t is the time) transmitted by the transmitting device. Symbol 502_l is a data symbol transmitted by the modulated signal zl(t) as symbol number u (in the time domain). Symbol 503_l is a data symbol transmitted by the modulated signal zl(t) as symbol number u+1.
Symbol 501_2 is for estimating the channel jitter of the modulated signal z2(t) (where t is the time) transmitted by the transmitting device. Symbol 502_2 is a data symbol transmitted by the modulated signal z2(t)
<img file="MX385274B_D0051.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY as the symbol number u (in the time domain) . Symbol 503_2 is a data symbol transmitted by the modulated signal zl(t) as symbol number u+1.
Here, symbols zl(t) and z2(t) having the same date-time (identical timing) are transmitted from the transmit antenna using the same (common/shared) frequency.
The following describes the relationships between the modulated signals zl(t) and z2(t) transmitted by the transmitting device and the received signals rl(t) and r2(t) received by the receiving device.
In Fig. 5, 504#l and 504#2 indicate the transmitting antennas of the transmitting device, while 505#l and 505#2 indicate the receiving antennas of the receiving device. The transmitting device transmits the modulated signal zl(t) from the transmit antenna 504#l and transmits the modulated signal z2(t) from the transmit antenna 504#2. Here, the modulated signals zl(t) and z2(t) are assumed to occupy the same (common/shared) frequency (bandwidth). The channel fluctuations of the transmitting device antennas and receiving device antennas are h<sub>or</sub>(t),h<sub>12</sub>(t),h<sub>21</sub>(t)yh<sub>22</sub>(t), respectively. Assuming that the receiving device receiving antenna 505#l receives the received signal rl(t) and that the receiving device receiving antenna 505#2 receives the signal
<img file="MX385274B_D0052.tif" />
received r2(t), the following relationship holds.
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
[Math 40] (formula 40) {jhW h<sub>2</sub>2^k<sup>z2</sup>^
Fig. 6 belongs to the weighting scheme (precoding scheme) and the phase shift scheme of the present embodiment. A weight unit 600 is a combined version of the weight units 308A and 308B of FIG. 3 . As shown, current si(t) and current s2(t) correspond to baseband signals 307A and 307B of FIG. 3 . That is, the currents si (t) and s2 (t) are the baseband signals made up of an I-phase component and a Q quadrature component in accordance with the correlation made by a modulation scheme such as QPSK, 16- QAM and 64-QAM. As indicated by the frame configuration of Figure 6, the stream sl(t) is represented as si(u) at symbol number u, as si(u+1) at symbol number u+1, etc. . Similarly, the current s2(t) is represented as s2(u) at symbol number u, as s2(u+l) at symbol number u+1, etc. Weighting unit 600 takes baseband signals 307A (si(t)) and 307B (s2(t)) as well as signal processing scheme information 315 of FIG. 3 as input, performs weighting accordingly. with schema information
<img file="MX385274B_D0053.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY processing signals 315, and outputs the weighted signals 309A (zl(t)) and 316B(z2'(t)) of Figure 3. The phase shifter 317B changes the signal phase weighted signal 316B(z2'(t)) and outputs the postphase shift signal 309B(z2(t)).
Here, given the vector W1 = (wll,wl2) of the first row of the fixed precoding matrix F, zl(t) can be expressed as Math 41 (formula 41) below.
[Mathematics 41] (formula 41) zl(í) = Wlx(5Í(í),y2(í))<sup>T</sup>
Similarly, given the vector W2 = (w21,w22) of the second row of the fixed precoding matrix F, and letting the phase shift formula applied by the phase shifter be y(t) , z2(t ) can be expressed as Math 42 (formula 42) below.
[Math 42] (formula 42) z2(f) = y(0xW2x(51(í),s2(í))<sup>T</sup>
Here, y(t) is a phase change formula that follows a predetermined scheme. For example, given a period (cycle) of four and datetime u, the phase change formula can be expressed as Math 43 (formula 43) below.
IMPI
MEXICAN INSTITUTE<sup>F</sup> OF THE PROPERTY
INDUSTRIAL
[Math 43] (formula 43) y(u) = e<sup>j0</sup>
Similarly, the phase change formula for date-time u+1 can be, for example, as given by Math 44 (formula 44).
[Mathematics 44] (formula 44) .π y(« + l) = e<sup>72</sup>
That is, the phase change formula for the date-time u+k can be expressed as Math 45 (formula 45).
[Math 45] (formula 45) .kn y(u + k) = e<sup>2</sup>
Note that Math 43 (Formula 43) through Math 45 (Formula 45) are given only as an example of regular phase change.
The regular phase change is not restricted to a period (cycle) of four. Potentially enhanced reception capabilities (error correction capabilities, to be exact) can be promoted in the receiving device
<img file="MX385274B_D0054.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY increasing the amount of the period (cycle) (this does not mean that a longer period (cycle) is better, although avoiding low amounts such as two is probably ideal).
Likewise, although Mathematics 43 (formula 43) to the
Mathematics 45 (formula 45) above represent a configuration in which a phase change is carried out through rotation by predetermined consecutive phases (in the formula above, each n/2), the phase change does not need to rotate one amount, but can be random. For example, according to the predetermined period (cycle) of y(t) , the phase can change by sequential multiplication, as shown in Math 46 (formula 46) and Math 47 (formula 47). The key point of regular phase shift is that the phase of the modulated signal changes regularly. The degree of the phase change is preferably as uniform as possible, such as from -n radians to π radians. However, since this describes a distribution, random changes are also possible.
[Mathematics 46] (formula 46)
<img file="MX385274B_D0055.tif" />
<img file="MX385274B_D0056.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
[Mathematics 47] (formula 47)
<img file="MX385274B_D0057.tif" />
<img file="MX385274B_D0058.tif" />
<img file="MX385274B_D0059.tif" />
<img file="MX385274B_D0060.tif" />
By itself, the weighting unit 60 0 of Figure 6 performs precoding using fixed and predetermined precoding weights, and the phase shifter 10 317B changes the phase of the input signal while regularly varying the degree of the change in phase. phase.
When a specialized precoding matrix is used in a LOS environment, quality is likely to improve tremendously. However, depending on the conditions of the direct waves, the phase and amplitude components of the direct wave can differ greatly from the specialized precoding matrix, when reception occurs. The LOS environment has certain rules. Therefore, the reception quality of the data is tremendously improved by means of a regular change 20 applied to a transmission signal that obeys those rules. The present invention provides a signal processing scheme for LOS environment enhancements.
Figure 7 illustrates an exemplary configuration of a receiving device 700 belonging to the present embodiment. The 703_X wireless unit receives as input the
<img file="MX385274B_D0061.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY signal 702_X that receives the antenna 7 01_X, performs processing such as frequency conversion, quadrature demodulation and the like, and outputs the baseband signal 704_X.
The channel jitter estimator 7 05_l of the modulated signal zl transmitted by the transmitting device takes the baseband signal 704_X as input, extracts the reference symbol 501_l for the channel estimate of Fig. 5, estimates the value of hn of Mathematics 40 (formula 40) and outputs the channel estimation signal 706_l.
The channel jitter estimator 7 05_2 of the modulated signal z2 transmitted by the transmitting device takes the baseband signal 704_X as input, extracts the reference symbol 501_2 for the channel estimate of Fig. 5, estimates the value of hi<sub>2</sub> of Math 40 (formula 40) and outputs the channel estimation signal 706_2.
Wireless unit 703_Y receives, as input, signal 702_Y received by antenna 701_X, performs processing such as frequency conversion, quadrature demodulation, and the like, and outputs baseband signal 704_Y.
The channel jitter estimator 7 07_l of the modulated signal zl transmitted by the transmitting device takes the baseband signal 704_Y as input, extracts the reference symbol 501_l for the channel estimate of Fig. 5, estimates
<img file="MX385274B_D0062.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY the value of h<sub>2i</sub> of Math 4 0 (formula 4 0) and outputs the channel estimation signal 708 1.
The channel jitter estimator 707_2 of the modulated signal z2 transmitted by the transmission device takes the baseband signal 704_Y as input, extracts the reference symbol 501_2 for the channel estimation of Fig. 5, estimates the value of h<sub>22</sub> of Math 40 (formula 40) and outputs the channel estimation signal 708_2.
A control information decoder 709 receives the baseband signal 704_X and the baseband signal 704_Y as input, detects the symbol 500_l indicating the transmission scheme of Fig. 5, and outputs a control scheme information signal. transmission 710 for the transmission device.
A signal processor 711 takes baseband signals 704X and 704_Y, channel estimation signals 706_1, 706_2, 708_l, and 708_2, and transmission scheme information signal 710 as input, performs detection and detection. decoding and then output the received data 712 1 and 712_2.
The operations of the signal processor 711 of FIG. 7 are described in detail below. Figure 8 illustrates an exemplary configuration of signal processor 711 pertaining to the present embodiment. As shown, the signal processor 711 is mainly comprised of an inner MIMO detector, software input/output decoders, and a coefficient generator. Non-Patent Literature 2 and Non-Patent Literature 3 describe an iterative decoding scheme using this structure. The MIMO system described in Non-Patent Literature 2 and Non-Patent Literature 3 is a spatial multiplexing MIMO system, while the present embodiment differs from Non-Patent Literature 2 and Non-Patent Literature 3 by describing a system MIMO that regularly changes phase over time while using the same precoding matrix. If we take the (channel) matrix H(t) from Math 36 (formula 36) , letting the precoding weight matrix of Figure 6 be F (here, a fixed precoding matrix that remains unchanged for a given signal received) and letting the phase change formula used by the phase shifter of Figure 6 be Y(t) (here, Y(t) changes at time t), then the receive vector R(t) = (rl(t),r2 (t))<sup>T</sup> and the current vector S(t) = (if (t),s2(t))<sup>T</sup>, the following function is derived:
[Mathematics 48] (formula 48)
R(t)= H(t)xY(t)xFxS(t) where κ(')= (oy(»)J
<img file="MX385274B_D0063.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Here, the receiving device may use Non-Patent Literature 2 and 3 decoding schemes in R(t) by computing H(t)xY(t)xF.
Accordingly, the coefficient generator 819 of FIG. 8 takes a transmission scheme information signal 818 (corresponding to 710 of FIG. 7) indicated by the transmission device (information to specify the fixed precoding matrix in use and the phase change pattern used when the phase changes) and outputs a signal processing scheme information signal 820.
The inner MIMO detector 803 takes the signal processing scheme information signal as input and performs iterative detection and decoding using the signal and the relationship thereof with Math 4 8 (formula 48). Its operations are described below.
The processing unit illustrated in Fig. 8 uses a processing scheme, as illustrated in Fig. 10, to perform iterative decoding (iterative detection). First, detection of a modulated signal (current) codeword (or frame) si and a modulated signal (current) codeword (or frame) s2 is performed. As a result, the software input/output decoder obtains the log-likelihood ratio of each bit of the modulated signal codeword (or frame) (current) si and of the modulated signal codeword (or frame) ( stream)
C^IMPI
MEXICAN INSTITUTE<sup>r</sup> OF THE PROPERTY
INDUSTRIAL s2. The log-likelihood ratio is then used to perform a second round of detection and decoding. Those operations are performed multiple times (those operations are hereinafter called iterative decoding (iterative detection)). The following operations focus on the scheme for creating the log-likelihood ratio of a symbol at a specific time within a frame.
In Fig. 8, a memory 815 takes baseband signal 801X (corresponding to baseband signal 704_X of Fig. 7), channel estimation group signal 802X (corresponding to channel estimation signals 706 1 and 706 2 of Figure 7), the baseband signal 801Y (corresponding to the baseband signal 704_Y of Figure 7), and channel estimation group signal 802Y (corresponding to channel estimation signals 708_l and 708_2 of Fig. 7) as input, execute (compute) H(t)xY(t)xF of Math 48 (formula 48 ) in order to perform iterative decoding (iterative detection) and stores the resulting matrix as a group of transformed channel signals. Memory 815 then outputs the signals described above as needed, specifically as the 816X baseband signal, the 817X channel estimation group transform signal, the 816Y baseband signal, and the 816Y channel estimation group transform signal. channel 817Y.
Subsequent operations are described by
<img file="MX385274B_D0064.tif" />
IMPI
Separate MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY for initial detection and for iterative decoding (iterative detection).
(Initial detection)
The inner MIMO detector 803 takes the baseband signal 801X, the channel estimation group signal 802X, the baseband signal 801Y and the channel estimation group signal 802Y as input. Here, the modulation scheme for the modulated signal (current) si and the modulated signal (current) s2 are taken to be 16-QAM.
The inner MIMO detector 803 first computes H(t)xY(t)xF from the channel estimation signal groups 802X and 802Y, thereby calculating a candidate signal point corresponding to the baseband signal 801X. Figure 11 represents such a calculation. In Figure 11, each black dot is a candidate signal point in the IQ plane. Since the modulation scheme is 16-QAM, there are 256 candidate signal points. (However, Figure 11 is only a representation and does not indicate all 256 candidate signal points). Letting the four bits transmitted in modulated signal si be bO, bl, b2, and b3 and the four bits transmitted in modulated signal s2 be b4, b5, b6, and b7, the candidate signal points corresponding to (bO, bl, b2 , b3, b4, b5, b6, b7) are found in figure 11. The squared Euclidean distance between each candidate signal point and each received signal point 1101 (corresponding to baseband signal 801X) is then computed. Euclidean distance squared
<img file="MX385274B_D0065.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY between each point is divided by the noise variance or<sup>2</sup>. Therefore, we calculate E<sub>x</sub>(b0, bl, b2, b3, b4, b5, b6, b7) . It means<sub>x</sub> is the squared Euclidean distance between a candidate signal point corresponding to (bO, bl, b2, b3, b4, bB, b6, b7) and a received signal point, divided by the noise variance. Here, each of the baseband signals and the modulated signals si and s2 is a complex signal.
Similarly, the inner MIMO detector 803 computes H(t)xY(t)xF from the channel estimation signal groups 802X and 802Y, computes the candidate signal points corresponding to the baseband signal 801Y, computes the squared Euclidean distance between each of the candidate signal points and the received signal points (corresponding to the 801Y baseband signal), and divides the squared Euclidean distance by the noise variance σ<sup>2</sup>. Therefore, we calculate E<sub>Y</sub>(b0, bl, b2, b3, b4, b5, b6, b7) . It means<sub>Y</sub> is the squared Euclidean distance between a candidate signal point corresponding to (bO, bl, b2, b3, b4, b5, b6, b7) and a received signal point, divided by the noise variance.
Then we compute E<sub>x</sub>(b0, bl, b2, b3, b4, b5, b6, b7) + E<sub>Y</sub>(b0, bl, b2, b3, b4, b5, b6, b7) = E(b0, bl, b2, b3, b4, b5, b6, b7) .
The indoor MIMO detector 803 outputs E(b0, bl, b2, b3, b4, b5, b6, b7) as a signal 804.
The 805A log-likelihood calculator takes
<img file="MX385274B_D0066.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY the signal 804 as input, calculates the log-likelihood of the bits bO, bl, b2, and b3, and outputs the log-likelihood signal 806A. Note that this log-likelihood calculation yields the one-bit log-likelihood to be 1 and the one-bit log-likelihood to be 0. The calculation scheme is as shown in Math 28 (Formula 28), Math 29 (Formula 29) and Math 30 (Formula 30) and details are given in Non-Patent Literature 2 and 3.
Similarly, log-likelihood calculator 805A takes signal 804 as input, calculates the log-likelihood of bits b0, bl, b2, and b3, and outputs log-likelihood signal 806B. A deinterpolator 807A takes log-likelihood signal 806A as input, performs deinterpolation corresponding to that of the interpolator (interpolator 304A of FIG. 3), and outputs deinterpolated log-likelihood signal 808A.
Similarly, a de-interpolator 807B takes log-likelihood signal 806B as input, performs deinterpolation corresponding to that of the interpolator (interpolator 304B of FIG. 3), and outputs the deinterpolated log-likelihood signal 808B.
The log-likelihood ratio calculator 809A takes the deinterpolated log-likelihood signal 808A as input, calculates the log-likelihood ratio of the bits encoded by the encoder 302A of FIG. 3,
<img file="MX385274B_D0067.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY and outputs the log-likelihood ratio signal 810A.
Similarly, the log-likelihood ratio calculator 809B takes the deinterpolated log-likelihood signal 808B as input, calculates the log-likelihood ratio of the bits encoded by the encoder 302B of FIG. 3, and outputs the ratio signal log-likelihood 810B.
The software I/O decoder 811A takes the log-likelihood ratio signal 810A as input, performs decoding, and outputs the decoded log-likelihood ratio 812A.
Similarly, the software input/output decoder 811B takes the log-likelihood ratio signal 810B as input, performs decoding, and outputs the decoded log-likelihood ratio 812B.
(Iterative Decoding (Iterative Detection), k Iterations)
The interpolator (813A) takes the kl<sup>Ava</sup> log-likelihood ratio 812A, decoded by the software I/O decoder as input, performs interpolation and outputs the interpolated log-likelihood ratio 814A. Here, the interpolation pattern used by interpolator 813A is identical to that of interpolator 304A in Figure 3.
Another interpolator (813B) takes kl<sup>Ava</sup> reason of
<img file="MX385274B_D0068.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY log-likelihood ratio 812B, decoded by the software input/output decoder as input, performs interpolation, and outputs the interpolated log-likelihood ratio 814B. Here, the interpolation pattern used by the other interpolator 813B is identical to that of the other interpolator 304B in Figure 3,
The indoor MIMO detector 803 takes the baseband signal 816X, the channel estimate group transformed signal 817X, the baseband signal 816Y, the channel estimate group transformed signal 817Y, the interpolated log likelihood ratio 814A and the interpolated log likelihood ratio 814B as input. Here, the 816X baseband signal, the 817X channel estimation group transform signal, the 816Y baseband signal, and the 817Y channel estimation group transform signal are used instead of the 801X baseband signal, the channel estimation group signal 802X, baseband signal 801Y and channel estimation group signal 802Y because the latter cause delays due to iterative decoding.
The iterative decoding operations of the inner MIMO detector 803 differ from the initial detection operations thereof in that the interpolated log-likelihood ratios 814A and 814B are used in the signal processing for the former. The indoor MIMO detector 803 first calculates E(b0, bl, b2, b3, b4, b5, b6, b7) in the same way as
<img file="MX385274B_D0069.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY for initial detection. In addition, the coefficients for Math 11 (Formula 11) and Math 32 (Formula 32) are computed from the interpolated log-likelihood ratios 814A and 814B. The value of E(b0, bl, b2, b3, b4, b5, b6, b7) is corrected using the coefficients thus calculated to obtain E'(b0, bl, b2, b3, b4, b5, b6, b7), which is output as the 804 signal.
Log-likelihood calculator 805A takes signal 804 as input, calculates the log-likelihood of bits b0, bl, b2, and b3, and outputs log-likelihood signal 806A. Note that this log-likelihood calculation yields the one-bit log-likelihood to be 1 and the one-bit log-likelihood to be 0. The calculation scheme is as shown in Mathematics 31 (formula 31) to Mathematics 35 (formula 35), and the details are given in Non-Patent Literature 2 and 3.
Similarly, log-likelihood calculator 805B takes signal 804 as input, calculates the log-likelihood of bits b4, b5, b6, and b7, and outputs log-likelihood signal 806A. The operations performed by the forward deinterpolator are similar to those performed for the initial detection.
Although Figure 8 illustrates the configuration of the signal processor when iterative detection is performed, this structure is not absolutely necessary, as they can
<img file="MX385274B_D0070.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY good reception improvements can be obtained only through iterative detection. As long as the necessary components for iterative detection are present, the configuration need not include interpolators 813A and 813B. In such a case, the inner MIMO detector 803 does not perform iterative detection.
The key point for the present embodiment is the calculation of H(t)xY(t)xF. As shown in Non-Patent Literature 5 and others, QR decomposition can also be used to perform initial detection and iterative detection.
In addition, as indicated in Non-Patent Literature 11, MMSE (least mean square error) linear operations and ZF (forced zero) linear operations can be performed based on H(t)xY(t)xF when performing detection. initial.
Figure 9 illustrates the configuration of a signal processor, different from that of Figure 8, that serves as the signal processor for the modulated signals transmitted by the transmission device of Figure 4. The point of difference of Figure 8 is the number of software input/output decoders. A software input/output decoder 901 takes log-likelihood ratio signals 810A and 810B as input, performs decoding, and outputs a decoded log-likelihood ratio 902. A distributor 903 takes the decoded log-likelihood ratio 902. as input for distribution.
<img file="MX385274B_D0071.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Otherwise, the operations are identical to those explained for figure 8.
As already described, when a transmission device according to the present embodiment using a MIMO system transmits multiple modulated signals from multiple antennas, changing the phase in time while multiplying by the precoding matrix as to change the phase regularly results in improvements in data reception quality for a receiving device in a LOS environment where direct waves are dominant, in contrast to a conventional spatial multiplexing MIMO system.
In the present embodiment and in particular in the configuration of the receiving device, the number of antennas is limited and explanations are given in this regard. However, the modality can also be applied to a larger number of antennas. In other words, the number of antennas of the receiving device does not affect the operations or the advantageous effects of the present embodiment.
Furthermore, although LDPC codes are described as a particular example, the present embodiment is not so limited. Also, the decoding scheme is not limited to the sum-product decoding example given for the software I/O decoder. Other software input/output decoding schemes can also be used, such as the BCJR algorithm, SOVA, and the algorithm
<img file="MX385274B_D0072.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Max-Log-Map. Details are provided in Non-Patent Literature 6.
Furthermore, although the present embodiment is described using a single carrier scheme, no limitation in that regard is intended. The present mode is also applicable to multi-carrier transmission. Accordingly, the present embodiment can also be realized using, for example, spread spectrum communications, OFDM (orthogonal frequency division multiplexing), SC-FDMA (carrier frequency division multiple access). Single Carrier), SC-OFDM (Single Carrier Orthogonal Frequency Division Multiplexing), Miniwave OFDM as described in Non-Patent Literature 7, etc. Also, in the present embodiment, symbols other than data symbols, such as pilot symbols (preamble, single word, etc.). or symbols conveying control information, may be arranged within the frame in any manner.
The following describes an example where OFDM is used as a multi-carrier scheme.
Figure 12 illustrates the configuration of a transmission device using OFDM. In Figure 12, components operating in the manner described for Figure 3 use identical reference numerals.
OFDM related processor 12OIA takes 309A weighted signal as input, performs processing on it
<img file="MX385274B_D0073.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY related to OFDM and outputs the 1202A transmission signal. Similarly, the OFDM-related processor 1201B takes the post-phase change 309B as input, performs OFDM-related processing on it, and outputs the transmission signal 1202A.
Figure 13/ illustrates an exemplary configuration of OFDM-related processors 1201A and 1201B and forward of Figure 12. Components 1301A through 1310A belong to 1201A through 312A of Figure 12, while components 1301B through 1310B belong to between 1201B and 312B.
Serial-to-parallel converter 1302A performs serial-to-parallel conversion on weighted signal 13OIA (corresponding to 3-weighted signal 09A of FIG. 12) and outputs parallel signal 1303A.
The reorderer 1304A takes the parallel signal 1303A as input, performs reordering on it, and outputs the reordered signal 1305A. The rearrangement is described in detail below.
The IFFT (Inverse Fast Fourier Transform) unit 1306A takes the reordered signal 1305A as input, applies an IFFT to it, and outputs the post-IFFT signal 1307A.
The 1308A wireless unit takes the 1307A post-IFFT signal as input, performs processing such as frequency conversion and amplification on it, and outputs the
<img file="MX385274B_D0074.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY modulated signal 1309A. Antenna 1310A then outputs the modulated signal 1309A as radio waves.
Serial-to-parallel converter 1302B performs serial-to-parallel conversion on weighted signal 1301B (corresponding to post-phase shift 309B of FIG. 12) and outputs parallel signal 1303B.
The reorderer 1304B takes the parallel signal 1303B as input, performs reordering on it, and outputs the reordered signal 1305B. The rearrangement is described in detail below.
The IFFT unit 1306B takes the reordered signal 1305B as input, applies the IFFT to it, and outputs the post-IFFT signal 1307B.
The wireless unit 1308B takes the post-IFFT signal 1307B as input, performs processing such as frequency conversion and amplification on it, and outputs the modulated signal 1309B. Antenna 1310A then outputs the modulated signal 1309B as radio waves.
The transmission device of Figure 3 does not use a multi-carrier transmission scheme. In this way, as shown in Fig. 6, the phase change is performed to achieve a period (cycle) of four and the post-phase change symbols are arranged with respect to the time domain. As shown in Fig. 12, when multi-carrier transmission such as OFDM is used, naturally the symbols change
<img file="MX385274B_D0075.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL precoded postphases can be arranged with respect to the time domain as in Figure 3, and this is true for each (sub-)carrier. However, for multicarrier transmission, the arrangement may also be in the frequency domain or in both the frequency domain and the time domain. The following describes those provisions.
Figures 14A and 14B indicate frequency on the horizontal axes and time on the vertical axes thereof, and illustrate an example of a symbol reordering scheme used by reorderers 1301A and 1301B of Figure 13. The frequency axes they are made up of (sub-)carriers 0 to 9. The modulated signals zl and z2 share common date-time (timing) indicators and use a common frequency band. Figure 14A illustrates a reordering scheme for the symbols of the modulated signal zl, while Figure 14B illustrates a reordering scheme for the symbols of the modulated signal z2. With respect to the symbols of the OIA weighted signal 13 input to the serial-to-parallel converter 13 02A, the assigned order is #0, #1, #2, #3, etc. Here, since the example is about a period (cycle) of four, #0, #1, #2, and #3 are equivalent to one period (cycle). Similarly, #4n, #4n+l, #4n+2, and #4n+3 (where n is a nonzero positive integer) are also equivalent to a period (cycle).
As shown in Fig. 14A, the symbols #0, #1, #2, #3, etc. are arranged in order, starting at the carrier
<img file="MX385274B_D0076.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
0. Symbols #0 through #9 are given timestamps $1, followed by symbols #10 through #19 are given timestamps #2, and so on. In a regular arrangement. Note that the modulated signals zl and z2 are the complex signals.
Similarly, with respect to the symbols of the weighted signal 1301B that are input to the serial-to-parallel converter 1302B, the assigned order is #0, #1, #2, #3, etc. Here, since the example is about a period (cycle) of four, a different phase shift is applied to each of #0, #1, #2, and #3, which are equivalent to one period (cycle). Similarly, a different phase shift is applied to each of #4n, #4n+l, #4n+2, and #4n+3 (where n is a nonzero positive integer), which are also equivalent to a period ( cycle)
As shown in Fig. 14B, the symbols #0, #1, #2, #3, etc. they are arranged in order, starting at carrier 0. Symbols #0 through #9 are given timestamps $1, followed by symbols #10 through #19 are given timestamps #2, and so on. In a regular arrangement.
Symbol group 1402 shown in FIG. 14B corresponds to one symbol period (cycle) when using the phase shift scheme of FIG. 6 . Symbol #0 is the symbol obtained using the phase at date-time u of figure 6, symbol #1 is the symbol obtained using the phase at date-time u+1 of figure 6, symbol #2 is the symbol obtained using the phase at date-time u+2 of figure 6 and symbol #3 is
<img file="MX385274B_D0077.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY the symbol obtained using the phase at date-time u+3 in Figure 6. Therefore, for any #x symbol, the #x symbol is the symbol obtained using the phase at date-time u in Figure 6 when x mod 4 is equal to 0 (that is, when the remainder of x divided by 4 is 0, with mod being the modulus operator), the symbol #x is the symbol obtained using the phase at date-time u+1 of Figure 6 when x mod 4 is equal to 1, the symbol #x is the symbol obtained using the phase at date-time u+2 in figure 6 when x mod 4 is equal to 2, and the symbol #x is the symbol obtained using the phase at date-time u+3 in figure 6 when x mod 4 is equal to 3.
In the present embodiment, the modulated signal zl shown in Fig. 14A has not undergone a phase shift.
Per se, when using a multi-carrier transmission scheme such as OFDM and different from single-carrier transmission, the symbols may be arranged with respect to the frequency domain. Of course, the symbol layout scheme is not limited to those illustrated in Figs. 14A and 14B. Additional examples are shown in Figures 15A, 15B, 16A, and 16B.
Figures 15A and 15B indicate the frequency on the horizontal axes and the time on the vertical axes thereof, and illustrate an example of a symbol reordering scheme used by the 13OIA and 1301B reorderers of Figure 13 that differs from that of the figures 14A and 14B. Figure 15A illustrates a
<img file="MX385274B_D0078.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY reordering scheme for the symbols of the modulated signal zl, while Figure 15B illustrates a reordering scheme for the symbols of the modulated signal z2. Figures 15A and 15B differ from Figures 14A and 14B in that different reordering schemes are applied to the symbols of the modulated signal zl and to the symbols of the modulated signal z2. In Fig. 15B, symbols #0 to #5 are arranged on carriers 4 to 9, symbols #6 to #9 are arranged on carriers 0 to 3, and this arrangement is repeated for symbols #10 to #19 . Here, as in Fig. 14B, the group of symbols 1502 shown in Fig. 15B corresponds to a period (cycle) of symbols when the phase shift scheme of Fig. 6 is used.
Figures 16A and 16B indicate frequency on the horizontal axes and time on the vertical axes thereof, and illustrate an example of a symbol reordering scheme used by reorderers 1301A and 1301B of Figure 13 that differs from that of figures 14A and 14B. Figure ISA illustrates a reordering scheme for the symbols of the modulated signal zl, while Figure 16B illustrates a reordering scheme for the symbols of the modulated signal z2 . Figures ISA and 16B differ from Figures 14A and 14B in that, while Figures 14A and 14B showed the symbols arranged on the sequential carriers, Figures ISA and 16B do not arrange the symbols on the sequential carriers. Obviously, in the case of figures ISA and 16B, they can be applied to the symbols of the modulated signal
<img file="MX385274B_D0079.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY zl and to the symbols of the modulated signal z2 reordering schemes different from those of figures 15A and 15B.
Figures 17A and 17B indicate frequency on the horizontal axes and time on the vertical axes thereof, 5 and illustrate an example of a symbol reordering scheme used by reorderers 1301A and 1301B of Figure 13 that differs from those of Figures 14A to 16B. Figure 17A illustrates a reordering scheme for the symbols of the modulated signal zl and Figure 17B illustrates a reordering scheme for the 10 symbols of the modulated signal z2. While Figures 14A through 16B show the symbols arranged with respect to the frequency axis, Figures 17A and 17B use the frequency and time axes together in a single arrangement.
While Fig. 6 describes an example where a phase change is performed in a period of four slots (cycle), the following example describes a period of eight slots (cycle). In Figures 17A and 17B, symbol group 1702 is equivalent to one symbol period (cycle) when using the phase shift scheme (i.e., to eight symbols) such that symbol #0 is the symbol obtained using the phase at date-time u, symbol #1 is the symbol obtained using the phase at date-time u+1, symbol #2 is the symbol obtained using the phase at date-time u+2, symbol #3 is the symbol obtained using the phase at date-time u+3, symbol #4 is the symbol obtained using the phase at date-time u+4 , the symbol
<img file="MX385274B_D0080.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY #5 is the symbol obtained using the phase at date-time u+5, symbol #6 is the symbol obtained using the phase at date-time u+6 and symbol #7 is the symbol obtained using the phase at date-time u+7. Therefore, for any symbol #x, the symbol #x is the symbol obtained using the phase at the date-time u when x mod 8 is equal to 0, the symbol #x is the symbol obtained using the phase at the date-time time u+1 when x mod 8 is equal to 1, the symbol #x is the symbol obtained using the phase in date-time u+2 when xmod 8 is equal to 2, the symbol #x is the symbol obtained using the phase at date-time u+3 when x mod 8 is equal to 3, the symbol #x is the symbol obtained using the phase at date-time u+4 when x mod 8 is equal to 4, the symbol #x is the symbol obtained using the phase at date-time u+5 when x mod 8 equals 5, the symbol #x is the symbol obtained using the phase at date-time u+6 when x mod 8 equals 6, and the symbol #x is the symbol obtained using the phase at date-time hour u+7 when x mod 8 is equal to 7. In Figs. 17A and 17B, four slots along the time axis and two slots along the frequency axis are used for a total of 4 x 2 = 8 slots, in which one symbol period (cycle) is arranged. Here, given mxn symbols per period (cycle) (i.e., mxn different phases are available for multiplication), then n intervals (carriers) in the frequency domain and m intervals in the time domain must be used to arrange the symbols of each period (cycle), so that m > n. This is because the wave phase
<img file="MX385274B_D0081.tif" />
IMPI
Direct data fluctuates slowly in the time domain relative to the frequency domain. Therefore, the present embodiment performs a regular phase shift that reduces the influence of direct steady waves. In this way, the phase change period (cycle) should preferentially reduce direct wave fluctuations. Therefore, m must be greater than n. Taking into account the above, the joint use of the time and frequency domains for the rearrangement, as shown in figures 17A and 17B, is preferred in relation to the use of either the frequency domain or the time domain alone, due to the strong probability that the direct waves will become regular. As a result, the effects of the present invention are more easily obtained. However, the rearrangement in the frequency domain can lead to diversity gain due to the fact that the frequency domain fluctuations are abrupt. By itself, the joint use of the frequency and time domains for rearrangement is not always ideal.
Figures 18A and 18B indicate frequency on the horizontal axes and time on the vertical axes thereof, and illustrate an example of a symbol reordering scheme used by reorderers 1301A and 130IB of Figure 13 that differs from that of Figures 17A and 14B. Figure 18A illustrates a reordering scheme for the symbols of the modulated signal zl, while Figure 18B illustrates a reordering scheme for the symbols of the modulated signal z2 . Similar to figures 17A and
<img file="MX385274B_D0082.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
17B, Figures 18A and 18B illustrate the joint use of the time and frequency domains. However, in contrast to Figures 17A and 17B, where the frequency domain is prioritized and the time domain is used for the secondary symbol layout, Figures 18A and 18B prioritize the time domain and use of the signal domain. frequency for the arrangement of secondary symbols. In FIG. 18B, symbol group 1802 corresponds to a symbol period (cycle) when the phase shift scheme is used.
In Figures 17A, 17B, 18A and 18B, the reordering scheme applied to the symbols of the modulated signal zl and the symbols of the modulated signal z2 may be identical or different as in Figures 15A and 15B. Both approaches allow to obtain a good reception quality. Also, in Figures 17A, 17B,
18A and 18B, the symbols may be arranged non-sequentially as in Figures 16A and 16B. Both approaches allow to obtain a good reception quality.
Figure 22 indicates the frequency on the horizontal axis and the time on the vertical axis thereof, and illustrates an example 20 of a symbol reordering scheme used by the reorderers 13OIA and 13 0IB of Figure 13 which differs from the preceding one. Figure 22 illustrates a regular phase change scheme using four intervals, similar to the date-time indicators u and u+3 in Figure 6. The characteristic feature of Figure 22 is that, although the symbols are reordered with respect to
<img file="MX385274B_D0083.tif" />
IMPI
In the frequency domain, when read along the time axis, a periodic shift of n (n = 1 in the example of Figure 22) symbols is evident. The group of frequency domain symbols 2210 in Figure 22 indicates four symbols to which the phase shift is applied in the timestamps ua u+3 of Figure 6.
Here, symbol #0 is obtained by phase shifting at date-time u, symbol #1 is obtained by phase shifting at date-time u+1, symbol #2 is obtaining by means of a phase change in the date-time u+2 and the symbol #3 is obtained by means of a phase change in the date-time u+3.
Similarly, for the group of frequency domain symbols 2220, symbol #4 is obtained via a phase shift at date-time u, symbol #5 is obtained via a phase shift at date-time u+1, symbol #6 is obtained by phase shifting date-time u+2 and symbol #7 is obtained by phase shifting date-time u+3 .
The phase change described above is applied to the symbol at date-time $1. However, in order to apply the periodic shift in the time domain, the following phase changes are applied to the groups of symbols 2201, 2202, 2203 and 2204.
For the group of time-domain symbols 22 01, symbol #0 is obtained by a phase shift in the
<img file="MX385274B_D0084.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY date-time u, symbol #9 is obtained through a phase change in date-time u+1, symbol #18 is obtained through a phase change in date- time u+2 and the symbol #2 7 is obtained by means of a phase change in the date-time u+3.
For the group of time-domain symbols 2202, symbol #28 is obtained via a phase shift at date-time u, symbol #1 is obtained via a phase shift at date-time u +1, symbol #10 is obtained by phase shifting at datetime u+2, and symbol #19 is obtained by phase shifting datetime u+3.
For the group of time-domain symbols 2203, symbol #20 is obtained by a phase change in date-time u, symbol #29 is obtained by a phase change in date-time u +1, symbol #2 is obtained by phase shifting at date-time u+2 and symbol #11 is obtained by phase shifting at date-time u+3.
For the group of time-domain symbols 2204, symbol #12 is obtained by a phase change in date-time u, symbol #21 is obtained by a phase change in date-time u +1, the symbol #3 0 is obtained by means of a phase change in the date-time u+2 and the symbol #3 is obtained by means of a phase change in the date-time u+3.
The characteristic feature of Figure 22 is seen in that, taking symbol #11 as an example, the two neighboring symbols of it that have the same date-time in the frequency domain
<img file="MX385274B_D0085.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY (#10 and #12) are both symbols that are changed using a different phase than symbol #11, and the two neighboring symbols of it that have the same carrier in the time domain (#2 and #20) are both symbols that are changed using a different phase than symbol #11. This is true not only for symbol #11, but also for any symbol that has two neighboring symbols in the frequency domain and the time domain. Therefore, the phase change is effectively carried out. This is highly likely to improve the reception quality of the data as the regularizing influence of direct waves is less likely to be received.
Although Fig. 22 illustrates an example where n - 1, the invention is not limited in that regard. The same can be applied to a case where n = 3. Also, although Figure 22 illustrates the modality of the effects described above by arranging the symbols in the frequency domain and advancing in the time domain so as to achieve the characteristic effect of imparting a periodic shift to the order of the symbol arrangement, for the the same effect the symbols can also be arranged randomly (or regularly).
Modality 2
In Mode 1 described above, the phase shift is applied to a weighted signal (precoded with a fixed precoding matrix) z(t). The following modalities describe various phase change schemes by which
<img file="MX385274B_D0086.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY can obtain the effects of Modality 1.
In the previously described embodiment, as shown in Figures 3 and 6, phase shifter 317B is configured to perform a phase shift on only one of the signals output by weighting unit 600.
However, the phase shift can also be applied before the weighting unit 600 is pre-encoded. In addition to the components illustrated in Figure 6, the transmitting device may also have weighting unit 600 before phase shifter 317B, as shown in Figure 25.
Under such circumstances, the following configuration is possible. Phase shifter 317B performs a regular phase shift with respect to baseband signal s2(t), which has been correlated according to a selected modulation scheme, and outputs s2 '(t) = s2(t)y(t) (where y(t) varies in time t) . The weighting unit 600 performs the premodification on s2't, outputs z2(t) = W2s2 '(t) (see Math 42 (formula 42)), and then the result is transmitted.
Alternatively, the phase shift can be performed on both the modulated signals si(t) and s2(t). By itself, the transmission device is configured to include a phase shifter that takes in both signals that are output by the weighting unit 600, as shown in Figure 26.
Like the 317B phase shifter, the phase shifter
<img file="MX385274B_D0087.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
317A performs a regular phase shift on the signal input, and as such shifts the signal phase zl'(t) pre-encoded by the weighting unit. A transmitter then outputs the post-phase change signal zl(t).
However, the rate of phase change applied by phase shifters 317A and 317B varies simultaneously in order to perform the phase shift shown in Fig. 26. (The following describes a non-limiting example of the phase shift scheme) . For date-time u, phase shifter 317A in Fig. 26 performs the phase shift such that zl(t) = yi(t)zl'(t), while phase shifter 317B performs the shift so that z2 (t) = y<sub>2</sub> (t) z2 ' (t) . For example, as shown in Figure 26, for date-time u, yi (u) = e<sup>j0</sup> and y2 (u) = e<sup>jn/2</sup>, for date-time u+1, yi(u+l) = e<sup>jn/4</sup> and y2(u+l) = e<sup>-:Í3n/4</sup>, and for date-time u+k, yr(u+k) = e<sup>jkn/4</sup> yy<sub>2</sub> (u+k) = θί^<sup>311</sup>/<sup>4</sup> - <sup>n</sup>/2) Here, the regular phase change period (cycle) may be the same for both phase shifters 317A and 317B or may vary for each.
Furthermore, as already described, a phase shift may be performed before the weighting unit is precoded. In such a case, the transmission device must be configured as illustrated in figure 27.
When a phase shift is performed on both modulated signals, each of the transmit signals, for example, is control information that includes information about
<img file="MX385274B_D0088.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY of the phase change pattern. Obtaining the control information, the receiving device knows the phase shift scheme by which the transmitting device regularly varies the shift, i.e. the phase shift pattern, and thus can demodulate (decode) the phase shifts. signals correctly.
Next, variants of the exemplary configurations shown in figures 6 and 25 are described with reference to figures 28 and 29. Figure 28 differs from figure 8 in the inclusion of the information of activation deactivation (ON/OFF) of the change of phase 2800 and in which the phase change takes place in only one of zl'(t) and z2 '(t) (that is, it takes place in one of zl'(t) and z2'(t), which have identical date-time indicators or a common frequency). Therefore, in order to perform the phase change in one of zl'(t) and z2'(t), the phase shifters 317A and 317B shown in Fig. 28 may each be ON and perform phase change or, deactivated (OFF) and do not perform the phase change. The ON/OFF information of the phase change 2800 is the control information for it. An information generator for signal processing schemes 314 shown in FIG. 3 outputs phase shift ON/OFF information 2800.
Phase shifter 317A in Figure 28 changes phase to produce zl(t) = yi(t)zl' (t) , while phase shifter 317B changes phase to produce z2(t) = y<sub>2</sub>(t)z2' (t) .
Here, a phase change is applied that has a period
<img file="MX385274B_D0089.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY (cycle) of four, for example, to zl' (t) . (Meanwhile, the phase of z2'(t) does not change). Therefore, for date-time u, yi (u) = e<sup>J</sup>° y y2(u) = 1, for date-time u+1, y^Ju+l) = e<sup>jn/2</sup> and y2(u+l) = 1, for date-time u+2, yi(u+2) = e<sup>jn</sup> y y2(u+2) = 1 and for date-time u+3 yi(u+3) = e<sup>j3n/2</sup> and y2(u+3) = 1.
Next, a phase change having a period (cycle) of four is applied, for example, to z2' (t). (Meanwhile, the phase of zl' (t) does not change). Therefore, for the date-time u+4, yiíu+4) = 1 yy<sub>2</sub>(u+4) = e^°, for date-time u+5, and<sub>x</sub>(u+5) = 1 and and<sub>2</sub>(u+5) = e<sup>jn</sup>^<sup>2</sup>, for date-time u+6, yx(u+6) = 1 and y2(u+6) = e<sup>jn</sup> y for date-time u+7 yx(u+7) = 1 yy<sub>2</sub>(u+7) = e<sup>j3n>/2</sup>.
Therefore, given the preceding examples.
for any 8k datetime, yi(8k) = e<sup>J</sup>° yy<sub>2</sub>(8k) =
1,
<td>for</td><td>any</td><td>date hour</td><td>8k+l, yi(8k+l)</td><td>= e^<sup>2</sup> Y</td>
<td>Y<sub>2</sub>(8k+l) .= 1, for</td><td>any</td><td>date hour</td><td>8k+2, and<sub>x</sub>(8k+2)</td><td>i = e<sup>jn</sup> Y</td>
<td>Y<sub>2</sub>(8k+2) = 1, for</td><td>any</td><td>date hour</td><td>8k+3, yi(8k+3)</td><td>= and<sup>j3n,/2</sup> Y</td>
Y<sub>2</sub>(8k+3) = 1, for any date-time 8k+4, yi (8k+4) = 1 yy<sub>2</sub> (8k+4) = e<sup>j0</sup>, for any date-time 8k+5, yi(8k+3) =lyy<sub>2</sub>(8k+5) = and<sup>jn/2</sup>, for any date-time 8k+6, and<sub>x</sub>(8k+6) =lyy<sub>2</sub>(8k+6)
<img file="MX385274B_D0090.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY = e<sup>jn</sup> / And for any date-time 8k+7, yi(8k+7) =lyy<sub>2</sub>(8k+7) = and<sup>j3n/2</sup>.
As already described, there are two intervals, one where the phase change occurs only at zl'(t) , and another where the phase change occurs only at z2'(t) . Likewise, the two intervals form a period of phase change (cycle). Although the preceding explanation describes the interval where the phase change occurs only at zl'(t) and the interval where the phase change occurs only at z2'(t) as equal, no limitation is provided in this regard . The two intervals may also differ. Furthermore, although the preceding explanation describes the pattern of a phase change with a period (cycle) of four only in zl'(t) and then the pattern of a phase change with a period (cycle) of four only in z2 '(t) , no limitation is provided in this regard. The phase changes can be performed at zl' (t) and z2' (t) in any order (for example, the phase change can alternate between being performed at zl'(t) and at z2'(t) or, can be done in random order).
Phase shifter 317A in Fig. 29 changes phase to produce si' (t) = y!(t)sl(t) , while phase shifter 317B changes phase to produce s2'(t) = y<sub>2</sub>(t)s2(t).
Here, a phase change with a period (cycle) of four is applied, for example, to sl(t). (Meanwhile, s2(t) remains unchanged.) Therefore, for the date-time u,
<img file="MX385274B_D0091.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY yi (u) = e<sup>j0</sup> and y2(u) = 1, for date-time u+1, yi(u+l) = e<sup>jn/2</sup> and y2(u+l) = 1, for date-time u+2, yi(u+2) = e<sup>jn</sup> y y2(u+2) = 1 and for date-time u+3, yi(u+3) = e<sup>j3n/2</sup> and y2(u+3) = 1.
Next, a phase change with a period (cycle) of four is applied, for example, to s2(t). (Meanwhile, sl(t) remains unchanged.) Therefore, for date-time u+4, yi(u+4) = 1 and y<sub>2</sub>(u+4) = e<sup>j0</sup>, for date-time u+5, yi(u+5) = 1 and y2(u+5) = e<sup>jn/2</sup>, for date-time u+6, yi(u+6) = l and y2(u+6) = e<sup>]n</sup> and for date-time u+7, yi(u+7) =lyy<sub>2</sub>(u+7) = e<sup>j3n/2</sup>.
Therefore, given the preceding examples, for any date-time 8k, yUSk) = e<sup>j0</sup> yy<sub>2</sub>(8k) = 1, for any date-time 8k+l, yi(8k+l) = e<sup>jn/2</sup> yy<sub>2</sub>(8k+l) = 1, for any date-time 8k+2, yi(8k+2) = e<sup>jn</sup> yy<sub>2</sub>(8k+2) = 1, for any date-time 8k+3, and<sub>x</sub>(8k+3) = e^<sup>3n/2</sup> yy<sub>2</sub>(8k+3) = 1, for any date-time 8k+4, yi(8k+4) =lyy<sub>2</sub>(8k+4) = e<sup>J</sup>°, for any date-time 8k+5, yi(8k+5) =lyy<sub>2</sub>(8k+5) = e^<sup>no/2</sup>, for any date-time 8k+6 , yi(8k+6) =lyy<sub>2</sub>(8k+6) = e<sup>jn</sup>, Y
<img file="MX385274B_D0092.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY for any date-time 8k+7, yi (8k+7) = 1 yy<sub>2</sub> (8k+7) = and<sup>j3n/2</sup>.
As already described, there are two intervals, one where the phase change occurs only at sl(t) and one where the phase change occurs only at s2(t) . Likewise, the two intervals form a period of phase change (cycle). Although the foregoing explanation describes the interval where the phase change is performed only at si(t) and the interval where the phase change is performed only at s2(t) as the same, no limitation is provided in this regard. The two intervals may also differ. Furthermore, although the preceding explanation describes the mode of phase change with a period (cycle) of four only in si(t) and then the mode of phase change with a period (cycle) of four only in s2(t) , no limitation is foreseen in this sense. The phase changes can be performed on sl(t) and s2(t) in any order (for example, they can alternate between being performed on sl(t) and s2(t), or they can be performed in random order).
Therefore, the receiving conditions under which the receiving device receives each transmission signal zl(t) and z2(t) are equalized. By periodically changing the phase of the symbols in the received signals zl(t) and z2(t), you can increase the chance that the error correcting codes will correct the errors, thus improving the received signal quality in the LOS environment. .
<img file="MX385274B_D0093.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Therefore, Mode 2 as already described can produce the same results as Mode 1 described above.
Although the present embodiment uses a single carrier scheme, ie time domain phase shift, as an example, no limitation is intended in that regard. The same effects can also be achieved using multicarrier transmission. Accordingly, the present embodiment can also be realized using, for example, spread spectrum communications, OFDM, SC-FDMA (single carrier frequency division multiple access), SC-OFDM, miniwave OFDM, as described below. described in Non-Patent Literature 7, etc. As described above, while the present embodiment explains the phase change as the change in phase with respect to the time domain t, alternatively the phase may change with respect to the frequency domain, as discussed in Mode 1. That is, considering the phase shift scheme in the time domain t described in the present embodiment and replacing t with f (where f is the ((sub-)carrier) frequency) leads to a phase shift applicable to the frequency domain . Furthermore, as already explained in relation to Mode 1, the phase shift scheme of the present embodiment is also applicable to the phase shift with respect to both the time domain and the frequency domain.
Therefore, although figures 6, 25, 26, and 27
<img file="MX385274B_D0094.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY illustrate phase changes in the time domain, the replacement of time t by the carrier f in each of figures 6, 25, 26 and 27 corresponds to a phase change in the frequency domain. In other words, replacing (t) by (t, f) where t is time and f is frequency corresponds to performing the phase shift in the time-frequency blocks.
Also, in the present embodiment, symbols other than data symbols, such as pilot symbols (preamble, single word, etc.) or symbols conveying control information, may be arranged within the frame in any manner.
Modality 3
Modality Forms 1 and 2, described above, explain the regular phase changes. Mode 3 describes a reception device admission scheme to obtain good received signal quality of the data, regardless of the reception device layout, considering the location of the reception device with respect to the transmission device.
Mode 3 refers to the arrangement of the symbols within the signals obtained by means of a phase shift.
Figure 31 illustrates an example of frame configuration for a portion of the symbols within a signal in the time-frequency domain, given a transmission scheme where
<img file="MX385274B_D0095.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY performs a regular phase change for a multicarrier scheme, such as OFDM.
First, an example is explained in which the phase shift is performed on one of two baseband signals, pre-encoded in the manner explained in Mode 1 (see Fig. 6).
(Although Figure 6 illustrates a time-domain phase shift, the shift of time t by carrier f in Figure 6 corresponds to a frequency-domain phase shift. In other words, replace (t) by (t, f) where t is the time and f is the frequency, corresponds to making phase changes in the time-frequency blocks).
Figure 31 illustrates the framing configuration of the modulated signal z2', which is input to phase shifter 317B of Figure 12. Each square represents a symbol (although both signals si and s2 are included for purposes of comparison). precoding, according to the precoding matrix, only one of signals si and s2) can be used.
Consider symbol 3100 on carrier 2 and date-time $2 in Figure 31. The carrier described here may alternatively be referred to as a subcarrier.
Within carrier 2, there is a very strong correlation between the channel conditions for symbol 3100 on carrier 2, datetime $2, and the channel conditions for the time-domain symbols closest to datetime $2 , that is, the token 3013 at date-time $1 and
<img file="MX385274B_D0096.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY the symbol 3101 at date-time $3 within carrier 2.
Similarly, for datetime $2, there is a very strong correlation between the channel conditions for symbol 3100 on carrier 2, datetime $2, and the channel conditions for the frequency domain symbols closest to carrier 2, that is, symbol 3104 on carrier 1, date-time $2, and symbol 3104 on date-time $2, carrier 3.
As already described, there is a very strong correlation between the channel conditions for symbol 3100 and the channel conditions for symbols 3101, 3102, 3103, and 3104.
The present description considers N different phases (N being an integer, N 2 ) for multiplication in a transmission scheme where the phase changes regularly. The symbols illustrated in figure 31 are indicated as e<sup>j0</sup>, for instance. That means that this symbol is the signal z2 ' of figure 6 with phase change through multiplication by e^°. That is, the values indicated in figure 31 for each of the symbols are the values of y(t) from Mathematics 42 (formula 42), which are also the values of z2 (t) = y<sub>2</sub>(t)z2<sup>r</sup> (t) described in Modality 2.
The present modality takes advantage of the high correlation in the existing channel conditions between the neighboring symbols in the frequency domain and/or the neighboring symbols in the time domain, in a symbol arrangement that enables the
<img file="MX385274B_D0097.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY reception device that receives the symbols with the changed phase obtains a high quality of data reception.
In order to achieve this high quality of data reception, conditions #1 and #2 are necessary.
(Condition #1)
As shown in Figure 6, for a transmission scheme involving a regular phase shift performed on the pre-encoded baseband signal z2' using multi-carrier transmission, such as OFDM, time X, carrier Y is a symbol to transmit the data (hereinafter the data symbol), the neighboring symbols in the time domain, i.e. at time Xl, carrier Y and at time X+l, carrier Y are also symbols of data, and a different phase shift must be performed on the precoded baseband signal z2' corresponding to each of the three data symbols, i.e. on the precoded baseband signal z2' at time X, carrier Y, at at time Xl, carrier Y and at time X+l, carrier Y.
(Condition #2)
As shown in Figure 6, for a transmission scheme involving a regular phase shift performed on the pre-encoded baseband signal z2' using multi-carrier transmission such as OFDM, time X, carrier Y is a symbol of data, the neighboring symbols in the frequency domain, that is, at time X, the carrier Yl and at
<img file="MX385274B_D0098.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY time X, carrier Y+l are also data symbols, and a different phase shift must be performed on the pre-encoded baseband signal z2' corresponding to each of the three data symbols, i.e. , in the precoded baseband signal z2' at time X, carrier Y, at time X, carrier Yl, and at time X, carrier Y+l.
Ideally, data symbols that satisfy Condition #1 should be present. Similarly, data symbols that satisfy Condition #2 must be present.
The grounds that support Conditions #1 and #2 are as follows.
There is a very strong correlation between the channel conditions of the given symbol of a transmission signal (hereinafter symbol A) and the channel conditions of symbols neighboring symbol A in the time domain, as already discussed. described.
Therefore, when three neighboring symbols in the time domain each have different phases, despite the degradation of the reception quality in the LOS environment (poor signal quality caused by the degradation of the conditions due to the phase relations of direct waves, despite the high quality of si in terms of SNR) for symbol A, the remaining two symbols to symbol A are very likely to provide good reception quality. As a result, a good received signal quality can be achieved after the
<img file="MX385274B_D0099.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY error correction and decoding.
Similarly, there is a very strong correlation between the channel conditions of the given symbol of a transmission signal (hereafter symbol A) and the channel conditions of symbols neighboring symbol A in the frequency domain, as already described.
Therefore, when three neighboring symbols in the frequency domain each have different phases, despite the degradation of the reception quality in the LOS environment (poor signal quality caused by the degradation of the conditions due to the relations of phase of direct waves despite the high signal quality in terms of SNR) for symbol A, the remaining two symbols neighboring symbol A are most likely to provide good reception quality. As a result, you can achieve good received signal quality after error correction and decoding.
By combining Conditions #1 and #2, it is likely that even higher data reception quality can be achieved for the receiving device. Therefore, the following Condition #3 can be derived.
(Condition #3)
As shown in Figure 6, for a transmission scheme involving a regular phase shift performed on the pre-encoded baseband signal z2' using the transmission
<img file="MX385274B_D0100.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY multicarrier such as OFDM, time X, carrier Y is a data symbol, neighboring symbols in the time domain, that is, at time Xl, carrier Y and at time X +l, carrier Y are also data symbols, and neighboring symbols in the frequency domain, i.e. at time X, carrier Yl and at time X, carrier Y+l are also data symbols, and a different phase shift must be performed on the precoded baseband signal z2' corresponding to each of these five data symbols, i.e. on the precoded baseband signal z2' at time X, carrier Y, at at time X, carrier Yl, at time X, carrier Y+l, at time Xl, carrier Y, and at time X+l, carrier Y.
Here, the different phase changes are as follows. Phase shifts are defined from 0 radians to 2Π radians. For example, for time X, carrier Y, a phase shift of is applied to the precoded baseband signal z2' of Figure 6, for time Xl, carrier Y, a phase shift of<sub>and</sub>Yo<sup>0x_1</sup>'<sup>Y</sup> to the precoded baseband signal z2 ' of Figure 6, for time X+l, carrier Y, a phase shift of e is applied<sup>jfe+1</sup>'<sup>Y</sup> to the precoded baseband signal z2 ' of Figure 6, such that 0 θχ,γ < 2Π, 0 -θχ-ι,γ < 2Π, and 0 θχ+ι,γ < 2Π, all units being in radians . Therefore, for Condition #1, it follows that ΘΧ)Υ # θχ-ι,γ, θχ,γ θχ+ι,γ, and that θχ-ι,γ # θχ+ι,γ Similarly, for the Condition
<img file="MX385274B_D0101.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY #2, follows that θχ,γ / θχ,γ-ι, θχ,γ / θχ,γ+ι, and that θχ,γ_ι / θ<sub>χ</sub>,<sub>γ+1</sub>. and, for Condition #3, it follows that θ<sub>χ</sub>,<sub>γ</sub> /θχ_ι,<sub>γ</sub>, θ<sub>Χ/Υ</sub> /θ<sub>χ+1</sub>,<sub>γ</sub>, θ<sub>Χ/Υ</sub> / θχ^, θ<sub>Χ/</sub>γ + θχ,Υ-1, θχ-Ι,Υ * θχ<sub>+1</sub>,γ, θχ-ΐ,γ * θχ,Υ-1, θχ_<sub>1(</sub>γ * θχ<sub>+1</sub>,γ, θχ<sub>+1</sub>,γ θχ.χ,γ, θχ<sub>+1</sub>,γ * θχ,γ+ι» and that θχ,γ-i Ζ θ<sub>χ</sub>,γ<sub>+1</sub>.
Ideally, a data token should satisfy Condition #3.
Figure 31 illustrates an example of Condition #3 where symbol A corresponds to symbol 3100. The symbols are arranged such that the phase by which the pre-encoded baseband signal z2' of Figure 6 is multiplied differs for symbol 3100, for both of its time-domain neighbor symbols 3101 and 3102, and for both of its frequency-domain neighbor symbols 3102 and 3104. Therefore, despite the degradation of the received signal quality of symbol 3100 to the receiver, a good signal quality is highly likely.<sup>in</sup> 1-<sup>ace</sup> neighboring signals, thus ensuring good signal quality after error correction
Figure 32 illustrates a symbol arrangement obtained by means of phase changes under these conditions.
As is evident from Fig. 32, with respect to any data symbol, a different phase shift is applied to each neighboring symbol in the time domain and in the frequency domain. By itself, it can improve the ability of the receiving device to correct errors.
In other words, in figure 32, when all the
<img file="MX385274B_D0102.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY neighboring symbols in the time domain are data symbols, Condition #1 is fulfilled in all X and all Y.
Similarly, in Figure 32, when all neighboring symbols in the frequency domain are data symbols, Condition #2 is met for all X's and all Y's.
Similarly, in Figure 32, when all neighboring frequency-domain symbols are data symbols and all neighboring time-domain symbols are data symbols, Condition #3 is met for all X's and all X's. the Y's
The following describes an example where a phase shift is performed on two pre-encoded baseband signals, communication or explained in Mode 2 (see Fig. 26).
When a phase shift is performed on the precoded baseband signal zl' and the precoded baseband signal z2' as shown in Fig. 26, various phase shift schemes are possible. Their details are explained below.
Scheme 1 involves a phase shift performed on the pre-encoded baseband signal z2' as already described, to achieve the phase shift illustrated in Figure 32. In Figure 32, a phase shift is applied having a period (cycle) of 10 to the pre-encoded baseband signal z2'. However, as already described, in order to satisfy Conditions #1, #2 and #3, the phase shift applied to the signal varies with time.
<img file="MX385274B_D0103.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY precoded baseband z2 ' on each (sub-)carrier. (Although such changes are applied in Figure 32 with a period (cycle) of ten, other phase change schemes are also possible). Then, as shown in Fig. 33, the phase shift performed on the pre-encoded baseband signal zl' produces a constant value ie one tenth of the value of the phase shift performed on the pre-encoded baseband signal z2'. In Fig. 33, for a period (cycle) (of phase change performed on the precoded baseband signal z2') including the date-time $1, the value of the phase shift performed on the precoded baseband signal zl ' that<sup>j0</sup>. Then, for the next period (cycle) (of the phase shift performed on the precoded baseband signal z2') that includes the date-time $2, the value of the phase shift performed on the precoded baseband signal zl' is and<sup>jn/9</sup>, etc.
The symbols illustrated in figure 33 are indicated as e<sup>J</sup>°, for example. That means that this symbol is the signal zl' of figure 26 in which a phase shift has been applied through multiplication by e<sup>J</sup>°. That is, the values indicated in figure 33 for each of the symbols are the values of zl' (t) = y<sub>2</sub>(t)zl' (t) described in Mode 2 for Yi(t) .
As shown in figure 33, the phase shift performed on the pre-encoded baseband signal zl' produces a constant value i.e. one tenth of the value of the phase shift
<img file="MX385274B_D0104.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY performed on the precoded baseband signal z2', so that the value of the postphase change varies with the amount of each period (cycle). (As already described, in figure 33, the value is e<sup>J</sup> for the first period (cycle) , e^''<sup>9</sup> for the second 5 period (cycle), etc.).
As already described, the phase shift performed on the pre-encoded baseband signal z2' has a period (cycle) of ten, but the period (cycle) can be effectively made greater than ten by taking into account the applied phase shift 10 to the precoded baseband signal zl' and to the precoded baseband signal z2'. Accordingly, it can improve the reception quality of the data for the receiving device.
Scheme 2 involves a phase shift of precoded baseband signal z2' as already described, to achieve the phase shift illustrated in Figure 32. In Figure 32, a phase shift with period ( cycle) from ten to the pre-encoded baseband signal z2'. However, as already described, in order to fulfill Conditions #1, #2 and #3, the phase shift applied to the pre-encoded baseband signal z2 on each (sub-)carrier varies with time. (Although such changes are applied in Figure 32 with a period (cycle) of ten, other phase change schemes are also possible). Then, as shown in figure 30, the phase change made in the rock!
?5 of precoded baseband zl' differs from that realized in the signal
<img file="MX385274B_D0105.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY precoded baseband z2 ', since it has a period (cycle) of three instead of ten.
The symbols illustrated in figure 30 are indicated as e<sup>j</sup>°, for example. That means that this symbol is the signal zl' of figure 26 to which a phase shift has been applied through multiplication by e<sup>Jo</sup>. That is, the values indicated in Fig. 30 for each of the symbols are the values of zl(t) = yi(t)zl'(t) described in Mode 2 for Yi (t).
As already described, the phase shift made to the precoded baseband signal z2' has a period (cycle) of ten, but taking into account the phase shifts applied to the precoded baseband signal zl' and the signal For the precoded baseband signals z2', the period (cycle) may effectively be equivalent to 30 for both the precoded baseband signals zl' and z2'. Consequently, the reception quality of the data can be improved for the receiving device. An effective way to apply Scheme 2 is to perform a phase shift on the precoded baseband signal zl' with a period (cycle) of N and perform a phase shift on the precoded baseband signal z2' with a period ( cycle) of M such that N and M are co-primes. By itself, taking into account both pre-encoded baseband signals zl' and z2', a period (cycle) of NxM can be easily achieved, effectively making the period (cycle) larger when N and M are co-primes.
<img file="MX385274B_D0106.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
The above describes an example of the phase change scheme relevant to "Mode 3". The present invention is not limited in that sense. As explained in connection with Modality Forms 1 and 2, a phase shift can be made with respect to the frequency domain or the time domain or, in the time-frequency blocks. A similar improvement can be obtained in the data reception quality for the receiving device in all cases.
The same is true for frames having a configuration different from that described above, where pilot symbols (SP) and symbols carrying control information are inserted between the data symbols. The details of phase change under such circumstances are as follows.
Figures 47A and 47B illustrate the framing of the modulated signals (the pre-encoded baseband signals) zl or zl' and z2' in the time-frequency domain. Figure 47A illustrates the frame configuration of the modulated signal (the pre-encoded baseband signals) zl or zl' while Figure 47B illustrates the frame configuration of the modulated signal (the pre-encoded baseband signals) z2'. In Figures 47A and 47B, 4701 marks the pilot symbols while 4702 marks the data symbols. Data symbols 4702 are symbols on which premodification or premodification and a phase change have been performed.
<img file="MX385274B_D0107.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Figures 47A and 47B, like Figure 6, indicate the symbol arrangement when a phase shift is applied to the precoded baseband signal z2' (although no phase shift is performed on the precoded baseband signal zl). ) . (Although Figure 6 illustrates a phase shift with respect to the time domain, shifting time t by carrier f in Figure 6 corresponds to a phase shift with respect to the frequency domain. In other words, replacing (t) by (t, f) where t is time and f is frequency corresponds to performing a phase shift in the time-frequency blocks). Therefore, the numerical values indicated in Figs. 47A and 47B for each of the symbols are the values of the pre-encoded baseband signal z2' after the phase change. No value is given for the symbols of the pre-encoded baseband signal zl' (zl), since no change is made to them.
The key point of Figures 47A and 47B is that the phase shift is performed on the data symbols of the pre-encoded baseband signal z2', ie, on the pre-encoded symbols. (The symbols under discussion, being pre-encoded, actually include both si and s2 symbols). Therefore, no phase change is made to the pilot symbols inserted at z2'.
Figures 48A and 48B illustrate the framing of the modulated signals (the pre-encoded baseband signals) zl or zl' and z2' in the time-frequency domain. Figure 48A illustrates the frame configuration of the signal
<img file="MX385274B_D0108.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL modulated (the pre-encoded baseband signals) zl or zl' while Figure 47B illustrates the framing of the modulated signal (the pre-encoded baseband signals) z2'. In Figures 48A and 48B, 4701 marks the pilot symbols while 4702 marks the data symbols. Data symbols 4702 are symbols on which precoding or precoding and a phase shift have been performed.
Figures 48A and 48B, like Figure 26, indicate the symbol arrangement when a phase shift is applied to the precoded baseband signal zl' and the precoded baseband signal z2'. (Although Figure 26 illustrates a phase shift with respect to the time domain, the shift of time t by carrier f in Figure 26 corresponds to a phase shift with respect to the frequency domain. In other words, replacing (t) by (t, f) where t is time and f is frequency corresponds to performing a phase shift in the time-frequency blocks). Therefore, the numerical values indicated in Figs. 48A and 48B for each of the symbols are the values of the pre-encoded baseband signal zl' and z2' after the phase change.
The key point of Fig. 47 is that a phase shift is performed on the data symbols of the pre-encoded baseband signal zl', that is, on the pre-encoded symbols thereof, and on the data symbols of the signal of precoded baseband z2', ie in the precoded symbols thereof. (The symbols under discussion, being precoded, in
<img file="MX385274B_D0109.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY actually include both symbols si and s2) . Therefore, it does not perform any phase change on the pilot symbols inserted in zl', nor on the pilot symbols inserted in z2'.
Figures 49A and 49B illustrate the framing of the modulated signals (the pre-encoded baseband signals) zl or zl' and z2' in the time-frequency domain. Figure 49A illustrates the frame configuration of the modulated signal (the pre-encoded baseband signals) zl or zl', while Figure 49B illustrates the frame configuration of the modulated signal (the pre-encoded baseband signal) z2' . In Figures 49A and 49B, 4701 marks pilot symbols, 4702 marks data symbols, and 4901 marks null symbols for which the in-phase component of the baseband signal I = 0 and the quadrature component Q = 0 As such, data symbols 4702 are symbols on which precoding or precoding and phase shifting have been performed. Figures 49A and 49B differ from Figures 47A and 47B in the configurable scheme for symbols other than data symbols. The times and carriers at which the pilot symbols are inserted in the modulated signal zl' are null symbols in the modulated signal z2'. Conversely, the times and carriers at which the pilot symbols are inserted in the modulated signal z2' are null symbols in the modulated signal zl'.
Figures 49A and 49B, like Figure 6, indicate the arrangement of symbols when a phase shift is applied to the
<img file="MX385274B_D0110.tif" />
100
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY pre-encoded baseband signal z2' (although no phase shift is performed on the pre-encoded baseband signal zl). (Although Figure 6 illustrates a phase shift with respect to the time domain, the shift of time t by carrier f in Figure S corresponds to a phase shift with respect to the frequency domain. In other words, replacing (t) by (t, f) where t is the time and f is the frequency corresponds to making a change phase shift in the time-frequency blocks). Therefore, the numerical values indicated in Figs. 4-9A and 4-9B for each of the symbols are the values of the pre-encoded baseband signal z2' after a phase shift is performed. No value is given for the pre-encoded baseband signal symbols zl' (zl), since no phase shift is performed on them.
The key point of Figures 49A and 49B is that a phase shift is performed on the data symbols of the pre-encoded baseband signal z2', ie, on the pre-encoded symbols. (The symbols under discussion, being pre-encoded, actually include both si and s2 symbols). Therefore, no phase change is made to the pilot symbols inserted at z2'.
Figures 50A and 50B illustrate the framing of the modulated signals (the pre-encoded baseband signals) zl or zl' and z2' in the time-frequency domain. Figure 50A illustrates the frame configuration of the signal
<img file="MX385274B_D0111.tif" />
101
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY modulated (the pre-encoded baseband signal) zl or zl', while Figure 50B illustrates the frame configuration of the modulated signal (the pre-encoded baseband signal) z2'. In Figures 50A and 50B, 4701 marks pilot symbols, 4702 marks data symbols, and 4901 marks null symbols for which the in-phase component of the baseband signal I = 0 and the quadrature component Q = 0. As such, data symbols 4702 are symbols on which precoding or precoding and a "phase shift" have been performed. Figures 50A and 50B differ from Figures 48A and 48B in the configurable pattern for symbols other than data symbols. The times and carriers at which the pilot symbols are inserted in the modulated signal zl' are null symbols in the modulated signal z2'. Conversely, the times and carriers at which the pilot symbols are inserted into the modulated signal z2' are null symbols in the modulated signal zl'.
Figures 50A and 50B, like Figure 26, indicate the symbol arrangement when a phase shift is applied to the precoded baseband signal zl' and the precoded baseband signal z2'. (Although Figure 26 illustrates a phase shift with respect to the time domain, the shift of time t by carrier f in Figure 26 corresponds to a phase shift with respect to the frequency domain. In other words, replacing (t) by (t, f) where t is time and f is frequency corresponds to making a phase shift in
<img file="MX385274B_D0112.tif" />
102
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY time-frequency blocks). Therefore, the numerical values indicated in Figs. 50A and 50B for each of the symbols are the values of the pre-encoded baseband signal zl' and z2' after a phase change.
The key point of Figures 50A and 50B is that a phase shift is performed on the data symbols of the pre-encoded baseband signal zl', i.e., on the pre-encoded symbols thereof, and on the data symbols of the baseband signal zl'. precoded baseband signal z2', ie, in the precoded symbols thereof. (The symbols under discussion, being pre-encoded, actually include both si and s2 symbols). Therefore, no phase change is made to the pilot symbols inserted in zl', nor to the pilot symbols inserted in z2'.
Figure 51 illustrates an exemplary configuration of a transmission device that generates and transmits the modulated signal having the frame configuration of Figures 47A, 47B, 49A and 49B. Its components perform the same operations as those in Figure 4 and use the same reference symbols.
In Fig. 51, weighting units 3 08A and 308B and phase shifter 317B only operate at times indicated by framing signal 313 as corresponding to data symbols.
In Figure 51, a pilot symbol generator 5101
<img file="MX385274B_D0113.tif" />
103
IMPI
MEXICAN INSTITUTE OF PROPERTY OR INDUSTRIAL (which also generates null symbols) outputs baseband signals 5102A and 5102B for a pilot symbol each time framing signal 313 indicates a pilot symbol (or a null symbol).
Although not indicated in the frame configurations of Figs. 47A to 50B, when precoding (or phase rotation) is not performed, e.g. eg when a modulated signal is transmitted using only one antenna (so that the other antenna does not transmit any signal) or when a space-time coding (particularly space-time block coding) transmission scheme is used to transmit the control information symbols, the framing signal 313 takes the control information symbols 5104 and the control information 5103 as input. When the framing signal 313 indicates a control information symbol, the baseband signals 5102A and 5102B thereof are output.
Wireless units 310A and 310B in Fig. 51 take multiple baseband signals as input and select a desired baseband signal according to signal framing 313. Wireless units 310A and 310B then apply OFDM signal processing and output the modulated signals 311A and 311B in accordance with the frame configuration.
Figure 52 illustrates a configuration
<img file="MX385274B_D0114.tif" />
104
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY Example of a transmission device that generates and transmits the modulated signal that has the frame configuration of figures 48A, 48B, 50A, and 50B. Its components perform the same operations as those in Figures 4 and 51 and use the same reference symbols. Figure 51 presents an additional phase shifter 317A that only operates when the framing signal 313 indicates a data symbol. At all other times, the operations are identical to those explained with respect to figure 51.
Figure 53 illustrates an exemplary configuration of a transmission device that differs from that of Figure 51. The following describes the points of difference. As shown in FIG. 53, phase shifter 317B takes multiple baseband signals as input. Then, when the framing signal 313 indicates a data symbol, the phase shifter 317B performs a phase shift on the pre-encoded baseband signal 316B. When the framing signal 313 indicates a pilot symbol (or null symbol) or a control information symbol, the phase shifter 317B pauses the phase shift operations so that the control symbols are output. the baseband signal as they are. (This can be interpreted as performing the forced rotation corresponding to e<sup>j0</sup>) .
A selector 5301 takes the multiple baseband signals as input and selects a baseband signal that has
<img file="MX385274B_D0115.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
105 a symbol indicated by framing signal 313 for output.
Figure 54 illustrates an exemplary configuration of a transmission device that differs from that of Figure 52. The following describes the points of difference. As shown in FIG. 54, phase shifter 317B takes multiple baseband signals as input. Then, when the framing signal 313 indicates a data symbol, the phase shifter 317B performs a phase shift on the pre-encoded baseband signal 316B. When the framing signal 313 indicates a pilot symbol (or null symbol) or a control information symbol, the phase shifter 317B pauses the phase shift operations so that the symbols of the frame are output. baseband signal as is. (This can be interpreted as performing the forced rotation corresponding to e<sup>j0</sup>) .
Similarly, as shown in Figure 54, phase shifter 5201 takes multiple baseband signals as input. Then, when the framing signal 313 indicates a data symbol, the phase shifter 5201 performs a phase shift on the pre-encoded baseband signal 309A. When the framing signal 313 indicates a pilot symbol (or null symbol) or a control information symbol, the phase shifter 5201 pauses phase shift operations such that
<img file="MX385274B_D0116.tif" />
106
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY output the baseband signal symbols as they are, (this can be interpreted as performing the forced rotation corresponding to e'<sup>0</sup>) .
The preceding explanations are given using pilot symbols, control symbols and data symbols as examples. However, the present invention is not limited in that regard. When symbols are transmitted using schemes other than precoding, such as single antenna transmission or transmission using space-time block coding, it is important not to perform a phase shift. Conversely, performing a phase shift on the symbols that have been pre-encoded is the key point of the present invention.
Accordingly, a characteristic feature of the present invention is that the phase shift is not performed on all symbols within the time-frequency domain frame configuration, but is only performed on signals that have been pre-encoded.
Modality 4
Embodiment Forms 1 and 2, described above, explain a regular phase change. Mode 3, however, describes the mode of a different phase change in neighboring symbols.
The present embodiment describes a phase shift scheme that varies according to the modulation scheme and the
<img file="MX385274B_D0117.tif" />
107
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY coding rate of the error correction codes used by the transmission device.
Table 1 below is a list of phase shift scheme settings corresponding to transmitting device settings and parameters.
Table 1
<td>Amount of transmission modulated signals</td><td>Schedule of modulation</td><td>Cup of coding</td><td>Pattern Change of phase</td>
<td> 2</td><td>#1: QPSK, #2: QPSK</td><td> #1: 1/2, #2 2/3</td><td>#1: #2:A</td>
<td> 2</td><td>#1: QPSK, #2: QPSK</td><td> #1: 1/2, #2: 3/4</td><td>#1: A, #2: B</td>
<td> 2</td><td>#1: QPSK, #2: QPSK</td><td> #1: 2/3, #2: 3/5</td><td>#1: A, #2: C</td>
<td> 2</td><td>#1: QPSK, #2: QPSK</td><td> #1: 2/3, #2: 2/3</td><td>#1: C, #2: -</td>
<td> 2</td><td>#1: QPSK, #2: QPSK</td><td> #1: 3/3, #2: 2/3</td><td>#1: D, #2: E</td>
<td> 2</td><td>#1: QPSK, #2: 16-QAM</td><td> #1: 1/2, #2: 2/3</td><td>#1: B, #2: A</td>
<td> 2</td><td>#1: QPSK, #2: 16-QAM</td><td> #1: 1/2, #2: 3/4</td><td>#1: A, #2: C</td>
<img file="MX385274B_D0118.tif" />
108
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
<td> 2</td><td>#1: QPSK, #2: 16-QAM</td><td> #1: 1/2, #2: 3/5</td><td>#1:-, #2:E</td>
<td> 2</td><td>#1: QPSK, #2: 16-QAM</td><td> #1: 2/3, #2: 3/4</td><td>#1: D, #2: -</td>
<td> 2</td><td>#1: QPSK, #2: 16-QAM</td><td> #1: 2/3, #2: 5/6</td><td>#1: D, #2: B</td>
<td> 2</td><td>#1: 16-QAM, #2: 16-QAM</td><td> #1: 1/2, #2: 2/3</td><td>#1: #2:E</td>
In Table 1, #1 denotes the Mode 1 si-modulated signal described above (the baseband signal si modulated with the modulation scheme set by the transmitting device) and #2 denotes the modulated signal s2 (the baseband signal). baseband s2 modulated with the modulation scheme established by the transmitting device). The coding rate column of Table 1 indicates the coding rate of the error correcting codes for modulation schemes #1 and #2. The phase shift pattern column of Table 1 indicates the phase shift scheme applied to the precoded baseband signals zl (zl') and z2 (z2'), as explained in Embodiment Forms 1 to 3 . Although phase change patterns are labeled A, B, C, D, E, etc., that refers to the applied degree of phase change, for example in a phase change pattern given by Math 46 (formula 46) and Mathematics 47 (formula 47) above. in the pattern column
<img file="MX385274B_D0119.tif" />
109
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY of phase change in Table 1, the hyphen means that no phase change is applied.
The modulation scheme and coding rate combinations listed in Table 1 are examples. Other modulation schemes (such as 128-QAM and 256-QAM) and code rates (such as 7/8) not listed in Table 1 may also be included. Also, as described in Mode 1, the error correction codes used for si and s2 may differ (Table 1 is given for cases where only one type of error correction codes is used, as in figure 4). Also, the same modulation scheme and coding rate can be used with different phase shift patterns. The transmitting device transmits information indicative of the phase change patterns to the receiving device. The receiving device specifies the phase shift pattern by cross-referencing the information and Table 1, then performs demodulation and decoding. When the modulation scheme and the error correction scheme determine a single phase shift pattern, while the transmitting device transmits the modulation scheme and the information regarding the error correction scheme, the receiving device knows the pattern. of phase change obtaining that information. By itself, the information pertaining to the phase change pattern is not strictly necessary.
In modes 1 to 3, the phase shift is applied
<img file="MX385274B_D0120.tif" />
110
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY to pre-encoded baseband signals. However, the amplitude can also be modified along with the phase in order to apply periodic and regular changes. Therefore, an amplification modification pattern can also be made that regularly modifies the amplitude of the modulated signals to be in accordance with Table 1. In such circumstances, the transmission device must include an amplification modifier that modifies the amplification after the weighting unit 308A or weighting unit 308B of FIG. 3 or 4 . Furthermore, the amplification modification can be performed only on one or both of the pre-encoded baseband signals zl(t) and z2(t) (in the former case, the amplification modifier is only needed after the weighting unit 308A and 308B).
Also, although not indicated in the above Table 1, also the correlation scheme can be changed regularly by the correlator, without a regular phase change.
That is, when the correlation scheme for the modulated signal sl(t) is 16-QAM and the correlation scheme for the modulated signal s2(t) is also 16-QAM, the correlation scheme applied to the modulated signal s2( t) can change regularly as follows: from 16-QAM to 16-APSK, to 16-QAM in the IQ plane, to a first mapping scheme that produces a different signal point pattern than 16-APSK, to 16- QAM on the IQ plane,
<img file="MX385274B_D0121.tif" />
111
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY to a second mapping scheme that produces a signal point pattern different from 16-APSK, etc. In this way, you can improve the reception quality of the data for the receiving device, much like the results obtained by a regular phase shift described above.
Furthermore, the present invention may use any combination of schemes for a regular phase shift, correlation scheme and amplitude, and the transmission signal may transmit taking all of these into account.
The present embodiment can be realized using single carrier schemes as well as multi-carrier schemes. Accordingly, the present embodiment can also be realized using, for example, spread spectrum communications, OFDM, SC-FDM, SC-OFDM, miniwave OFDM as described in Non-Patent Literature 7, etc. As already described, the present embodiment teaches changing the phase, amplitude, and correlation schemes by making phase, amplitude, and correlation scheme modifications with respect to the time domain t. However, much like Mode 1, the same changes can be made with respect to the frequency domain. That is, considering the modification of the phase, amplitude, and time-domain correlation scheme t described in the present embodiment and replacing t with f (where f is the ((sub-)carrier) frequency) leads to the modification of the phase, amplitude and correlation scheme applicable to the domain
<img file="MX385274B_D0122.tif" />
112
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY of frequency. Furthermore, the modification of the phase, amplitude, correlation scheme of the present embodiment is also applicable to the modification of the phase, amplitude, correlation scheme in both the time domain and the frequency domain.
Also, in the present embodiment, symbols other than data symbols, such as pilot symbols (preamble, single word, etc.) or symbols conveying control information, may be arranged within the frame in any manner.
Al modality
The present embodiment describes a scheme for regularly changing the phase when encoding is performed using block codes as described in Non-Patent Literature 12 15, such as LDPC QC (quasi cyclic) codes (can be used not only QC-LDPC codes but also LDPC codes), concatenated LDPC and BCH (Bose-Chaudhuri-Hocquenghem) codes, turbo codes or duo-binary turbo codes using tail bits, etc. The following example considers a case where two currents si and s2 are transmitted. However, when the encoding has been done using block codes and control information or the like is not required, the number of bits making up each encoded block is the same as the number of bits making up each block code (it may still be included control information etc. described below). When the encoding is
<img file="MX385274B_D0123.tif" />
113
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY performed using block codes or the like and control information or the like (for example, CRC (cyclic redundancy check) transmission parameters are required), then the number of bits constituting each encoded block is the sum of the number of bits that make up the block codes and the number of bits that make up the information.
Figure 34 illustrates the varying amounts of symbols and intervals required in each encoded block when block codes are used. Figure 34 illustrates the varying numbers of symbols and intervals required in each coded block when block codes are used if, for example, two streams si and s2 are transmitted as indicated by the transmission device of Figure 4, and the device transmission has only one encoder. (Here, the transmission scheme may be any single-carrier scheme or multi-carrier scheme, such as OFDM).
As shown in Figure 34, when block codes are used, there are 6000 bits that make up a single coded block. In order to transmit those 6,000 bits, the number of symbols required depends on the modulation scheme, which is 3,000 symbols for QPSK, 1,500 symbols for 16-QAM, and 1,000 symbols for 64-QAM.
Then, since the transmission device of Figure 4 transmits two streams simultaneously, 1500 of the aforementioned 3000 symbols are assigned to si
<img file="MX385274B_D0124.tif" />
114
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY necessary when the modulation scheme is QPSK and the other 1500 symbols are assigned to s2. Thus, 1500 slots are required to transmit the 1500 symbols (hereinafter, slots) for each of si and s2 .
By the same reasoning, when the modulation scheme is 16-QAM, it takes 750 slots to transmit all the bits that make up a single coded block, and when the modulation scheme is 64-QAM, it takes 500 slots to transmit all the bits that make up a single coded block. bits that make up a single coded block.
The following describes the relationship between the intervals defined above and the multiplication phase, as relevant to schemes for a regular phase change.
Here, five different phase shift values (or phase shift sets) are assumed to be ready for use in the scheme for a regular phase shift. That is, five different phase shift values (or phase shift sets) have been prepared for the phase shifter of the transmission device in Fig. 4 (equivalent to the period (cycle) of Mode Forms 1 to 4) (As in Figure 6, five phase shift values are needed to perform a phase shift with a period (cycle) of five on the pre-encoded baseband signal z2' only. Also, as in Figure 26, two phase shift values are needed for each interval in order to perform the phase shift on both baseband signals.
<img file="MX385274B_D0125.tif" />
115
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY precoded zl' and z2 '. Those two phase shift values are called the phase shift set. Therefore, five phase change sets should ideally be prepared in order to perform the phase change with a period (cycle) of five under such circumstances. Those five phase shift values (or phase shift sets) are expressed as PHASE [0] , PHASE [ 1 ] , PHASE [2] , PHASE[3] and PHASE[4].
Regarding the previously described 1500 slots necessary to transmit the 6000 bits that constitute a single coded block when the modulation scheme is QPSK, PHASE [0] is used in the 300 slots, PHASE [1] is used in the 300 slots, PHASE[2] is used in all 300 slots, PHASE[3] is used in all 300 slots, and PHASE[4] is used in all 300 slots. This is due to the fact that any deviation in the use of phases causes a great influence to be exerted by the most frequently used phase, since the receiving device depends on such an influence in relation to the quality of data reception.
Similarly, for the previously described 700 slots needed to transmit the 6000 bits that make up a single coded block when the modulation scheme is 16-QAM, PHASE[0] is used in all 150 slots, PHASE[1] is used in all 150 slots, PHASE[2] is used on all 150 slots, PHASE[3] is used on all 150 slots, and PHASE[4] is used on all 150 slots.
<img file="MX385274B_D0126.tif" />
116
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Likewise, for the previously described 500 slots necessary to transmit the 6000 bits that constitute a single coded block when the modulation scheme is 64-QAM, PHASE[0] is used in all 100 slots, PHASE[1] is used in all 100 slots, PHASE[2] is used on all 100 slots, PHASE[3] is used on all 100 slots, and PHASE[4] is used on all 100 slots.
As already described, a scheme for a regular phase shift requires the preparation of N phase shift values (or phase shift sets) (where the N different phases are expressed as PHASE[0], PHASE[1] , PHASE [2] ... PHASE[N-2], PHASE[Nl]). Thus, in order to transmit all the bits that make up a single coded block, PHASE[0] is used on the K<sub>either</sub> intervals, PHASE [1] is used on Ki intervals, PHASE [i] is used on Ki intervals (where i = 0, 1, 2..JSF-1; i.e. 0^i^Nl, i being a integer), and PHASE [Nl] is used in the Kn-i intervals, so Condition #A01 is met.
(Condition #A01)
K<sub>either</sub> = Ki ...= Ki = ... Kn-i. That is, K.<sub>a</sub> =K<sub>b</sub> (Va and Xb where a, b, = 0, 1, 2 ... Nl, a # b) .
Then, when a communication system that supports multiple modulation schemes selects such a supported modulation scheme to use, Condition #A01 for the supported modulation scheme is preferably met.
However, when multiple schemas are supported
<img file="MX385274B_D0127.tif" />
117
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY modulation, each such modulation scheme typically uses symbols that transmit a different number of bits per symbol (although it may happen that some use the same number), Condition #A01 may not be met in some modulation schemes. In such a case, the following condition is applied instead of Condition #A01.
(Condition #A02)
The difference between K<sub>a</sub> and Kb satisfies 0 or 1. That is, |Ka - Kb| satisfies 0 or 1 (Va, Md, where a, b = 0, 1, 2 ... Nl, a * b)
Figure 35 illustrates the varying amounts of symbols and intervals required in two coded blocks when block codes are used. Figure 35 illustrates the varying amounts of symbols and intervals required in each coded block when block codes are used if, for example, two streams si and s2 are transmitted as indicated by the transmission device of Figure 3 and Figure 12, and the transmission device has two encoders. (Here, the transmission scheme may be any single-carrier scheme or multi-carrier scheme, such as OFDM).
As shown in Figure 35, when block codes are used, there are 6000 bits that make up a single coded block. In order to transmit those 6,000 bits, the number of symbols required depends on the modulation scheme, which is 3,000 symbols for QPSK, 1,500 symbols for 16-QAM, and 1,000 symbols for QPSK.
<img file="MX385274B_D0128.tif" />
118
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY for 64-QAM.
The transmission device of Figure 3 and the transmission device of Figure 12 each transmit two streams at a time, and have two encoders. By themselves, the two streams each transmit different code blocks. Therefore, when the modulation scheme is QPSK, two coded blocks extracted from si and s2 are transmitted within the same slot, eg first coded block extracted from si is transmitted, then a second coded block extracted from s2 is transmitted. So, 3000 slots are needed to transmit the first and second coded blocks.
By the same reasoning, when the modulation scheme is 16-QAM, it takes 1500 slots to transmit all the bits that make up the two coded blocks, and when the modulation scheme is 64-QAM, it takes 1000 slots to transmit all the bits. bits that make up the two coded blocks.
The following describes the relationship between the intervals defined above and the multiplication phase, as relevant to schemes for a regular phase change.
Here, five different phase shift values (or phase shift sets) are assumed to be ready for use in the scheme for a regular phase shift. That is, five different phase shift values (or shift sets
<img file="MX385274B_D0129.tif" />
119
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY of phase) have been prepared for the phase shifters of the transmission devices of figures 3 and 12 (equivalent to the period (cycle) of Modality Forms 1 to 4) (as in figure 6 , five phase shift values are needed to perform a phase shift with a period (cycle) of five on the pre-encoded baseband signal z2' only. Furthermore, as in Fig. 26, two phase shift values are needed for each slot in order to perform the phase shift on both the pre-encoded baseband signals zl' and z2'. Those two phase shift values are called the phase shift set. Therefore, five phase change sets should ideally be prepared to phase change with a period (cycle) of five under such circumstances. Those five phase shift values (or phase shift sets) are expressed as PHASE [0] , PHASE [1] , PHASE [2] , PHASE[3] , and PHASE [4].
For the previously described 3000 slots needed to transmit the 6000x2 bits that constitute a single coded block when the modulation scheme is QPSK, PHASE [0] is used in all 600 slots, PHASE [1] is used in all 600 slots, PHASE [1] is used in all 600 slots, PHASE [2] is used in all 600 slots, PHASE [3] is used in all 600 slots, and PHASE [4] is used in all 600 slots. This is due to the fact that any deviation in the use of phases causes a great influence which must be exerted by the most frequently used phase, since the receiving device depends on such an influence for the reception quality of the data.
<img file="MX385274B_D0130.tif" />
120
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Also, in order to transmit the first coded block, PHASE[0] is used in 600-time intervals, PHASE[1] is used in 600-time intervals, PHASE[2] is used in 600-time intervals, PHASE[3] is used at intervals of 600 times, and PHASE[4] is used at intervals of 600 times. Also, in order to transmit the second coded block, PHASE[0] is used in the intervals of 600 times, PHASE[1] is used in the intervals of 600 times, PHASE[2] is used in the intervals of 600 times, PHASE[3] is used at intervals of 600 times, and PHASE[4] is used at intervals of 600 times.
Similarly, for the previously described 1500 slots needed to transmit the 6000x2 bits that make up the two coded blocks when the modulation scheme is 16-QAM, PHASE[0] is used in all 300 slots, PHASE[1] is used in all 300 slots, PHASE[2] is used on all 300 slots, PHASE[3] is used on all 300 slots, and PHASE[4] is used on all 300 slots.
Also, in order to transmit the first coded block, PHASE[0] is used in 300-time intervals, PHASE[1] is used in 300-time intervals, PHASE[2] is used in 300-time intervals, PHASE [3] is used at intervals of 300 times, and PHASE [4] is used at intervals of 300 times. Also, in order to transmit the second coded block, PHASE[0] is used in the intervals of 300 times, PHASE[1] is used in the intervals of 300 times, PHASE[2] is used in the intervals
<img file="MX385274B_D0131.tif" />
121
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY 300 times, PHASE[3] is used in the intervals of 300 times, and PHASE[4] is used in the intervals of 300 times.
Similarly, for the previously described 1000 slots needed to transmit the 6000x2 bits that make up the two coded blocks when the modulation scheme is 64-QAM, PHASE[0] is used in all 200 slots, PHASE[1] is used in all 200 slots, PHASE[2] is used on all 200 slots, PHASE[3] is used on all 200 slots, and PHASE[4] is used on all 200 slots.
Also, in order to transmit the first coded block, PHASE[0] is used in the intervals of 200 times, PHASE[1] is used in the intervals of 200 times, PHASE[2] is used in the intervals of 200 times, PHASE [3] is used at intervals of 200 times, and PHASE [4] is used at intervals of 200 times. Also, in order to transmit the second coded block, PHASE[0] is used in the intervals of 200 times, PHASE[1] is used in the intervals of 200 times, PHASE[2] is used in the intervals of 200 times, PHASE[3] is used at intervals of 200 times, and PHASE[4] is used at intervals of 200 times.
As already described, a scheme for regularly changing the phase requires the preparation of phase change values (or phase change sets) expressed as PHASE[0] , PHASE[1] , PHASE[2] ... PHASE [N-2] , PHASE[Nl] . By itself, in order to transmit all the bits that make up two coded blocks, PHASE[0] is used on the K<sub>either</sub> intervals, PHASE [1] is used on the K<sub>2</sub>
<img file="MX385274B_D0132.tif" />
122
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY intervals, PHASE[i] is used in the intervals (where i = 0, 1, 2...N-1) , and PHASE[Nl] is used in the K<sub>N</sub>_! intervals, so that Condition #A03 is met.
(Condition #A03)
K<sub>either</sub> = Ki ...= Ki = ... K<sub>H</sub>_Yo. That is, K.<sub>a</sub> =K<sub>b</sub> (Va and Vd where a, b, =0,1,2 ... Nl, a # b) .
Also, in order to transmit all the bits that make up the first coded block, PHASE[0] of K is used<sub>0/1 </sub>times, PHASE [1] is used from K^i times, PHASE [i] is used from Κι,ι times (where i = 0, 1, 2...N-1) , and PHASE [Nl] is used from Κν-ι,ι times, so that Condition #A04 is fulfilled.
(Condition #A04)
Ko,i = Κι,ι = -Ki,i = -Kn-i,i. That is, Ka,i = K<sub>b</sub>,i (Va and Vi where a, b, = 0, 1, 2 ... Nl, aí b) .
Also, in order to transmit all the bits that make up the second coded block, Ko's PHASE [0] is used,<sub>2 </sub>Sometimes, PHASE [1] of K is used<sub>lz2</sub> Sometimes, PHASE [i] of Ki is used<sub>r2</sub> times (where i = 0, 1, 2...N-1) , and PHASE[N-1] of Kn-i,2 times is used, so Condition #A05 is met.
(Condition #A05)
Ko,2<sup>=</sup> Ki,2<sup>=</sup> — Ki,2 — ··· Κν-ι,2· Εθ say, Ka>2<sup>=</sup> Kb/2 (Vi and V) where a, b, =0, 1, 2 ... Nl, a + b) .
Then, when a communication system that supports multiple modulation schemes selects which supported modulation scheme to use, they should preferably meet
<img file="MX385274B_D0133.tif" />
123
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY Condition #A03, #A04 and #A05 for the admitted modulation scheme.
However, when multiple modulation schemes are supported, each such modulation scheme typically uses symbols that transmit a different number of bits per symbol (although it may happen that some use the same number), Conditions #A03, #A04 may not be met and #A05 in some modulation schemes. In such a case, the following conditions apply instead of Condition #A03, #A04 and #A05.
(Condition #A06)
The difference between Ka and K<sub>b</sub> satisfies 0 or 1. That is, | K*-K<sub>b</sub>| satisfies 0 or 1 (Va, Vb, where a, b = 0, 1, 2 ... Nl, a A b) (Condition #A0 7)
The difference between K<sub>a/1</sub> and K<sub>b</sub>,i satisfies 0 or 1. That is, |Ka,i - Kb,i| satisfies 0 or 1 (Va, Vb, where a, b = 0, 1, 2 ... Nl, a / b) (Condition #A08)
The difference between K<sub>a</sub>.2 and K<sub>b)2</sub> satisfies 0 or 1. That is, |Ka<sub>/2</sub> -Kb,2| satisfies 0 or 1 (Va, Vb, where a, b = 0, 1, 2 ... Nl, a A b)
As already described, the offset between the phases used to transmit the coded blocks is eliminated by creating a relationship between the coded block and the multiplication phase. In this way, you can improve the quality of
<img file="MX385274B_D0134.tif" />
124
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY reception of the data for the reception device.
In the present embodiment, N phase change values (or phase change sets) are needed to perform a phase change with a period (cycle) of N with the scheme for a regular phase change. So the N phase shift values (or phase shift sets) PHASE[0], PHASE[1], PHASE[2] ... PHASE[N-2], and PHASE[Nl] are prepared. However, there are schemes for rearrangement of the phases in the established order with respect to the frequency domain. In this sense, no limitation is foreseen. The N phase shift values (or phase shift sets) may also shift the phases of the blocks in the time domain or in the time-frequency domain to obtain a symbol arrangement as described in Mode 1. Although the preceding examples explain a phase shift scheme with a period (cycle) of N, the same effects can be obtained by using N phase shift values (or phase shift sets) randomly. That is, the N phase shift values (or phase shift sets) are not always needed for a regular period (cycle). As long as the conditions described above are met, great improvements in data reception quality can be made for the receiving device.
Also, given the existence of modes for spatial multiplexing MIMO schemes, MIMO schemes that use a fixed precoding matrix, encoding schemes
<img file="MX385274B_D0135.tif" />
125
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY of space-time blocks, single current transmission and schemes using a regular phase change (the transmission schemes described in Modality Forms 1 to 4), the transmission device (broadcasting station, station base) you can select any of those transmission schemes.
As described in Non-Patent Literature 3, spatial multiplexing MIMO schemes involve the transmission of signals si and s2, which are correlated using a selected modulation scheme, on each of two different antennas. As described in Mode Forms 1 to 4, MIMO schemes using a fixed precoding matrix involve performing precoding only (without any phase shift). Also, space-time block coding schemes are described in Non-Patent Literature 9, 16 and 17. Single stream transmission schemes involve transmitting the signal si, correlated to a selected modulation scheme, from an antenna after to perform default processing.
Schemes using multi-carrier transmission such as OFDM involve a first carrier group consisting of multiple carriers and a second carrier group consisting of multiple carriers different from the first carrier group, etc., such that multi-carrier transmission is performed with multiple carrier groups. For each carrier group, you can use any of the
<img file="MX385274B_D0136.tif" />
126
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY spatial multiplexing MIMO schemes, MIMO schemes using a fixed precoding matrix, space-time block coding schemes, single stream transmission, and schemes using a regular phase shift. In particular, schemes using a regular phase shift in a selected group of (sub-)carriers are preferably used to perform the present embodiment.
When a phase shift is performed, then for example a phase shift value for PHASE[i] of X radians is performed on just a pre-encoded baseband signal, the phase shifters of Figures 3, 4, 5, 12 , 25, 29, 51 and 53 multiply the pre-encoded baseband signal z2 ' by e<sup>jX</sup>. Then a phase shift, for example, effected by a phase shift set for PHASE[i] of X radians and Y radians, which is performed on both pre-encoded baseband signals, the phase shifters of Figs. 26, 27, 28, 52 and 54 multiply the pre-encoded baseband signal z2 ' by e<sup>jX</sup> and multiply the pre-encoded baseband signal zl' by e<sup>jY</sup>.
Bl modality
The following describes an exemplary configuration of an application of the transmission schemes and reception schemes explained in the embodiments and a system using the application.
Figure 36 illustrates the configuration of a system that includes devices that execute the transmission schemes
<img file="MX385274B_D0137.tif" />
127
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY and reception schemes described in the preceding modalities. As shown in Fig. 36, the devices that implement the transmission schemes and reception schemes described in the preceding embodiments include various receivers such as a broadcast station, a 3611 television, a 3612 DVD recorder, a STB ) 3613, a 3620 computer, a 3641 vehicle-mounted television, a 3630 mobile phone, etc., within a 3600 digital broadcast system. Specifically, the broadcast station 3601 uses a transmission scheme explained in the above-described embodiments to transmit multiplexed data, in which video, audio, and other data are multiplexed over a predetermined transmission band.
Signals transmitted by broadcast station 3601 are received by an antenna (such as antenna 3660 or 3640) built into or externally connected to each of the receiving devices. Each receiver obtains the multiplexed data using the reception schemes explained in the previously described modes to remodulate the signals received by the antenna. Therefore, the digital broadcasting system 3600 can achieve the effects of the present invention, as explained in the above-described embodiments.
The video data included in the multiplexed data is encoded with a video coding method in accordance with a standard such as MPEG-2.
<img file="MX385274B_D0138.tif" />
128
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY for group of experts in mobile images), MPEG4-AVC (acronym in English for advanced video coding), VC-1 or other similar. The audio data included in the multiplexed data is encoded with an audio coding method in accordance with a standard such as Dolby AC-3 (Audio Coding), Dolby Digital Plus, MLP (Meridian Lossless Packing), DTS (Digital Theater Systems), DTS-HD, PCM (Pulse Code Modulation) or the like.
Figure 37 illustrates the configuration of a receiver 7900 executing a reception scheme set forth in the previously described embodiments. The 3700 receiver corresponds to a receiver included in one of the 3611 television, 3612 DVD recorder, 3613 STB, 3620 computer, 3641 vehicle-mounted television, 3630 mobile phone, etc., in Figure 36. Receiver 3700 includes a tuner 3701 which converts a high frequency signal received by an antenna 3760 into a baseband signal, and a demodulator 3702 which remodulates the thus converted baseband signal to obtain the multiplexed data. The demodulator 3702 executes a reception scheme explained in the previously described embodiments and thus achieves the effects of the present invention as already explained.
Receiver 3700 further includes a stream interface 3720 that demultiplexes the audio and video data from the multiplexed data obtained by demodulator 3702, a
<img file="MX385274B_D0139.tif" />
129
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY 3704 signal processor that decodes the video data obtained from the demultiplexed video data into a video signal by applying a . corresponding video decoding method and decodes the audio data obtained from the demultiplexed audio data into an audio signal by applying a corresponding audio decoding method, an audio output unit 3706 which outputs the decoded audio signal to through a speaker or other similar device, and a video output unit 3707 that outputs the decoded video signals to a display or similar device.
When, for example, a user uses a remote control 3750, the information corresponding to a selected channel (selected program (television) or audio broadcast) is transmitted to an operation input unit 3710. Afterwards, the receiver 3700 performs the processing in the received signal, which receives the antenna 3760, which includes the demodulation of the signal corresponding to the selected channel, the error correction decoding, etc., in order to obtain the received data. At this point, the receiver 3700 obtains the control symbol information which includes the information about the transmission scheme (the transmission scheme, the modulation scheme, the error correction scheme, etc. of the previously described modes) ( as described using figures 5 and 41) of the control symbols included in the signal corresponding to the selected channel. By itself, the 3700 receiver
130 you can correctly set the receive operations, demodulation scheme, error correction scheme etc. , thus enabling the data included in the data symbols transmitted by the broadcasting station (base station) to be obtained. Although the preceding description is given for an example where the user uses remote control 3750, the same operations hold when the user presses a selection key built into receiver 3700 to select a channel.
According to this configuration, the user can watch the programs received by the 3700 receiver.
Receiver 3700 pertinent to the present embodiment further includes a drive 3708 which may be a magnetic disk, optical disk, nonvolatile semiconductor memory, or similar recording medium. Receiver 3700 stores the data included in the demultiplexed data obtained through demodulation by demodulator 3702 and error correction decoding (in some circumstances, data obtained through demodulation by demodulator 3702 may not be subject to demodulation). to error correction In addition, the receiver 3700 may perform additional processing after error correction. The same goes here for similar statements concerning other components), the data corresponding to such data (for example, the data obtained through the compression of such data), the data
<img file="MX385274B_D0140.tif" />
131
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY obtained through the processing of audio and video, etc., in the 3708 unit. Here, an optical disc is a recording medium, such as DVD (digital versatile disc) or BD (Blu-ray disc). ), i.e. readable and writable using a laser beam. A magnetic disk is a floppy disk, hard disk, or similar recording medium on which information can be stored by using magnetic flux to magnetize a magnetic body. A non-volatile semiconductor memory is a recording medium, such as flash memory or ferroelectric random access memory, ka of a semiconductor element or elements. Specific examples of nonvolatile semiconductor memory include an SD card that uses flash memory and a Flash SSD (Solid State Drive). Of course, the specific types of recording media mentioned herein are merely examples. They can also use other types of recording media.
According to this structure, the user can record and store the programs received by the receiver 3700 and thereby watch the programs at a certain time after the broadcast by reading the data recorded therein from the medium.
Although the preceding explanations describe receiver 3700 that stores the multiplexed data obtained through demodulation performed by demodulator 3 7 02 and error correction decoding in unit 3 708, a portion of the data may instead be extracted and recorded. included in the multiplexed data. When services are included
<img file="MX385274B_D0141.tif" />
132
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY dissemination of data or similar content together with the audio and video data in the multiplexed data obtained through the demodulation performed by the 3702 demodulator and the error correction decoding, the audio and video data can be extracted from the multiplexed data remodulated by demodulator 3702 and stored as new multiplexed data. Also, unit 3708 may store the audio data or video data included in the multiplexed data obtained through demodulation performed by demodulator 3 7 02 and error correction decoding as new multiplexed data. The content of the aforementioned data broadcast service, included in the multiplexed data, may also be stored in unit 3708.
Likewise, when a television, recording device (for example, a DVD recorder, BD recorder, HDD recorder, SD card or the like) or mobile phone incorporating the receiver 3700 of the present invention receives the multiplexed data obtained through through demodulation performed by the 3702 demodulator and error correction decoding that includes the data to correct software defects used to operate the television or recording device, to correct software defects to prevent personal information and recorded data from being leaked, etc., such software defects can be corrected by installing the data on the television or recording device. In this way, correct
<img file="MX385274B_D0142.tif" />
133
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY defects in the 3700 receiver through the inclusion of data to correct defects in the 3700 receiver software. Consequently, the television, recording device, or mobile phone that incorporates the 3700 receiver may be made to operate more reliably.
Here, for example, the stream interface 3703 performs the process to extract a portion of the data included in the multiplexed data obtained through the demodulation performed by the demodulator 3702 and the error correction decoding. Specifically, the stream interface 3703 demultiplexes the various data included in the multiplexed data remodulated by the demodulator 3702, such as audio data, video data, broadcast data service content, etc., as instructed to do so by a undiagrammed controller such as a CPU. The stream interface 3703 then extracts and multiplexes only the indicated demultiplexed data, thus generating new multiplexed data. The data to be extracted from the demultiplexed data can be determined by the user or can be determined in advance according to the type of recording medium.
According to such a structure, the receiver 37 0 0 can extract and record only the necessary data in order to view the recorded program. In this way, the amount of data to be recorded can be reduced.
Although the preceding explanation describes the unit
<img file="MX385274B_D0143.tif" />
134
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
3708 as by storing the multiplexed data obtained through the demodulation performed by the demodulator 3 702 and the error correction decoding, the video data included in the multiplexed data thus obtained may be converted using a video encoding method different from the encoding method of original video applied to it, thereby reducing the amount of data or the bit rate of the data. Unit 3708 may then store the converted video data as new multiplexed data. Here, the video encoding method used to generate the new video data may conform to a different standard than the one used to generate the original video data. Alternatively, the same video encoding method can be used with different parameters. Similarly, the audio data included in the multiplexed data obtained through the demodulation performed by the demodulator 3 702 and the error correction decoding may be converted using an audio coding method different from the original audio coding method applied to them. Unit 3708 may also store the converted audio data as the new multiplexed data.
Here, for example, the stream interface 3703 or the signal processor 3704 perform the process by which the audio or video data included in the multiplexed data obtained through the demodulation performed by the demodulator
<img file="MX385274B_D0144.tif" />
135
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
3702 and error correction decoding, are converted as to reduce the amount of data or the bit rate of the data. Specifically, stream interface 3703 demultiplexes the various data included in the demodulator multiplexed data by demodulator 3702, such as audio data, video data, broadcast data service content, etc., as instructed to make it a diagrammed controller such as a CPU. The signal processor 3 7 04 then performs the processing to convert the thus demultiplexed video data using a video coding method different from the original video coding method applied thereto, and performs the processing to convert the audio data thus demultiplexed using a video coding method different from the original audio coding method applied to them. As instructed by the controller, the stream interface 3703 then multiplexes the converted audio and video data, thereby generating new multiplexed data. Signal processor 3704, in accordance with instructions from the controller, may perform conversion processing on either the video data or audio data alone or it may perform conversion processing on both types of data. In addition, the user can specify or determine in advance the amounts of video data and audio data or the bit rate thereof to be obtained by conversion, according to the type of the recording medium.
<img file="MX385274B_D0145.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
136
According to such a structure, the receiver 3 700 can modify the amount of data or the bit rate of the audio and video data for storage according to the data storage capacity of the recording medium, or according to the speed of reading or writing the data of the 3708 drive. Therefore, programs can be stored on the drive even though the storage capacity of the recording medium is less than the amount of multiplexed data obtained through demodulation by demodulator 3702 and error correction decoding or that the read or write speed of the data is less than the bit rate of the demultiplexed data obtained through the demodulation performed by the 3702 demodulator. By itself, the user can watch the programs at any given time after the broadcast by reading the recorded data.
Receiver 3700 further includes a stream output interface 3709 that transmits the multiplexed data, demultiplexed by demodulator 3702, to external devices via communication medium 3730. The current output interface 3709 may be, for example, a wireless communications device that transmits the modulated multiplexed data to an external device using a wireless transmission scheme conforming to a wireless communications standard such as Wi-Fi™ (IEEE 802.11a, IEEE 802.11b, IEEE 802.llg, IEEE 802.11η, etc.), WiGig, WirelessHD,
<img file="MX385274B_D0146.tif" />
137
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Bluetooth, ZigBee, etc., through a wireless medium (corresponding to the communications medium 373 0). The 3709 current output interface may also be a wired communications device that transmits the modulated multiplexed data to an external device using a communications scheme conforming to a wired communications standard such as Ethernet™, USB (Universal Serial Bus), PLC (power line communication) , HDMI (random definition multimedia interface), etc., via a wired transmission path (corresponding to the 3730 communications medium) connected to the 3709 current output interface.
In accordance with this configuration, the user may use an external device with the multiplexed data received by receiver 3700 using the receive scheme set forth in the previously described embodiments. The use of the multiplexed data by the user here includes the use of the multiplexed data to view in real time on an external device, to record the multiplexed data with a recording unit included in an external device, and to transmit the multiplexed data from an external device. external to even another external device.
Although the foregoing explanations describe receiver 3700 which outputs the multiplexed data obtained through demodulation by demodulator 3702 and error correction decoding via the interface
<img file="MX385274B_D0147.tif" />
138
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY 3709 stream output, a portion of the data included in the multiplexed data may instead be extracted and output. For example, when data broadcast service content or the like is included together with audio and video data in the multiplexed data obtained through demodulation performed by demodulator 3 702 and error correction decoding, the audio and video can be extracted from the multiplexed data obtained through demodulation performed by demodulator 3702 and error correction decoding, and stream output interface 3709 can multiplex them and output them as new multiplexed data. In addition, the stream output interface 3709 can store any of the audio data or video data included in the multiplexed data obtained through demodulation by demodulator 3 702 and error correction decoding as new multiplexed data. .
Here, for example, the stream interface 3703 performs the process to extract a portion of the data included in the multiplexed data obtained through the demodulation performed by the demodulator 3702 and the error correction decoding. Specifically, the stream interface 3703 demultiplexes the various data included in the multiplexed data demodulated by the demodulator 3702, such as audio data, video data, streaming service content
<img file="MX385274B_D0148.tif" />
139
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY dissemination of data, etc., as instructed to do so by a diagrammed controller such as a CPU. The stream interface 3703 then •extracts and multiplexes only the indicated demultiplexed data, thus generating new multiplexed data. The data to be extracted from the demultiplexed data can be determined by the user or can be determined in advance according to the 3709 stream output interface type.
According to this structure, the receiver 3 7 00 can extract and output only the required data to an external device. Thus, less multiplexed data is output using less communication bandwidth.
Although the foregoing explanation describes the stream output interface 3709 as outputting the multiplexed data obtained through the demodulation performed by the demodulator 3702 and error correction decoding, the video data included in the multiplexed data thus obtained may converted using a video encoding method different from the original video encoding method applied to them, such as to reduce the amount of data or the bit rate of the data. The stream output interface 3709 may then output the converted video data as new multiplexed data. Here, the video encoding method used to generate the new video data may conform to a different standard than the one used to generate the original video data. As an alternative,
<img file="MX385274B_D0149.tif" />
140
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY can use the same video encoding method with different parameters. Similarly, the audio data included in the multiplexed data obtained through the demodulation performed by the demodulator 3702 and the error correction decoding may be converted using an audio coding method different from the original audio coding method applied to such as to reduce the amount of data or the bit rate of the data. The stream output interface 3709 may then output the converted audio data as new multiplexed data.
Here, for example, the stream interface 3703 or the signal processor 3704 performs the process by which the included audio or video data is converted into the multiplexed data obtained through the demodulation performed by the demodulator 3702 and the decoding error correction such as to reduce the amount of data or the bit rate of the data. Specifically, the stream interface 3703 demultiplexes the various data included in the multiplexed data demodulated by the demodulator 3702, such as audio data, video data, data broadcast service content, etc., as instructed to make it a diagrammed controller. The signal processor 3704 then performs the processing to convert the thus demultiplexed video data using a different video encoding method than the originally applied video encoding method.
<img file="MX385274B_D0150.tif" />
141
IMPI
MEXICAN INSTITUTE OF PROPERTY OR INDUSTRIAL to them, and performs the processing to convert the audio data thus demultiplexed using a video coding method different from the original audio coding method applied to them. As instructed by the controller, the stream interface 3703 multiplexes the converted audio and video data, thereby generating new multiplexed data. Signal processor 3704, in accordance with instructions from the controller, may perform conversion processing on either the video data or audio data alone or it may perform conversion processing on both types of data. In addition, the amounts of video data and audio data or the bit rate thereof to be converted can be specified by the user or determined in advance according to the type of Streaming Interface 3709.
According to this structure, the receiver 3 700 can modify the bit rate of the video and audio data for output according to the communication speed with the external device. In this way, even though the communication speed with an external device is lower than the bit rate of the multiplexed data obtained through the demodulation performed by the 3702 demodulator and the error correction decoding, outputting the new data multiplexed from the current output interface to the external device, the user can use the new data
<img file="MX385274B_D0151.tif" />
142
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY multiplexed with other communications devices.
Receiver 3700 further includes an audiovisual output interface 3711 that outputs audio and video signals decoded by signal processor 3704 to the external device via an external communications medium. Audiovisual output interface 3711 may be, for example, a wireless communications device that transmits modulated audiovisual data to an external device using a wireless transmission scheme conforming to a wireless communications standard such as Wi-Fi™ (IEEE 802.11a , IEEE 802.11b, IEEE 802.llg, IEEE 802.11η, etc.), WiGig, WirelessHD, Bluetooth, ZigBee, etc. through a wireless medium. The 3709 power output interface may also be a wired communications device that transmits the modulated audiovisual data to an external device using a communications scheme conforming to a wired communications standard such as Ethernet™, USB, PLC, HDMI, etc. . via a wired transmission path connected to the 3709 current output interface. Also, the current output interface 3709 may be a terminal for connecting a cable that outputs analog video and audio signals as is.
According to such a structure, the user can use the audio signals and video signals decoded by the signal processor 3704 with an external device.
In addition, the 3700 receiver includes an input unit
<img file="MX385274B_D0152.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
143 operation 3710 that receives user operations as input. The receiver 3700 performs according to the control signals inputted by the operation input unit 3710 according to user operations, for example, turning the power ON/OFF, changing the channel that is received, turning the subtitle display ON/OFF, switching between languages, switching the volume output by the 3706 audio output unit, and various other operations, including changing the settings of receivable channels and the like.
Receiver 3700 may further include functionality to display an antenna level that represents received signal quality while receiver 3700 receives a signal. The antenna level can be, for example, an index showing the quality of the received signal, calculated according to the RSSI (received signal strength indicator), the strength of the magnetic field of the received signal, the C/N ratio (carrier to noise), BER, packet error rate, frame error rate, channel status information, etc., received by the 3700 receiver and indicating the level and quality of a received signal. In such circumstances, the 3702 demodulator includes a signal quality calibrator that measures RSSI, magnetic field strength of the received signal, C/N ratio, BER, packet error rate, error rate
144 of frames, channel status information, etc. In response to user operations, receiver 3700 displays the antenna level (signal level, signal quality) in a user-recognizable format on video display unit 3707. The antenna level display format (signal level, signal quality) can be a numerical value displayed according to RSSI, magnetic field strength of the received signal, C/N ratio, BER, rate packet error rate, frame error rate, channel status information, etc. , or it can be an image display that varies according to the RSSI, the magnetic field strength of the received signal,<sup>re</sup>he<sup>ac</sup>C/N ion, BER, packet error rate, frame error rate, channel status information, etc. The 3700 receiver can display multiple antenna levels (signal level, signal quality), calculated for each stream if,<sup>s2/</sup> ® tc., which are demultiplexed using the reception scheme explained in the previously described embodiments, or it can be a single antenna level (signal level, signal quality) calculated for all such currents. When the video data and audio data that make up a program are transmitted hierarchically, the signal level (signal quality) can also be displayed for each hierarchical level.
According to the preceding structure, the user is given knowledge of the antenna level (signal level, signal strength) numerically or visually during reception using
<img file="MX385274B_D0153.tif" />
145
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY reception schemes explained in the previously described.
Although the preceding example describes receiver 3700 as including audio output unit 3706, video display unit 3707, unit 3708, power output interface 3709, and audiovisual output interface 3711, all of these components are not strictly necessary. As long as receiver 3700 includes at least one of the components described above, the user may use the multiplexed data obtained through demodulation performed by demodulator 3702 and error correction decoding. Any receptor can be freely combined with the components described above according to the use of the scheme.
Multiplexed data
The following is a detailed description of an exemplary multiplexed data configuration. The data configuration typically used in broadcast is an MPEG-2 Transport Stream (TS). Therefore, the following description sets forth an example related to MPEG2-TS. However, the data pattern of the multiplexed data transmitted by the transmission and reception schemes explained in the above-described embodiments is not limited to MPEG2-TS. The advantageous effects of the previously described modalities also
146 they can be achieved using any other data structure.
Figure 38 illustrates an exemplary configuration for multiplexed data. As shown, the multiplexed data are elements that make up programs (or events that are a portion thereof) currently provided by various services. For example, one or more video streams, audio streams, presentation graphics (PG) streams, interactive graphics (IG) streams, and other such elements are multiplexed to obtain the multiplexed data. When a broadcast program provided by the multiplexed data is a movie, the video streams represent the main video and sub-video of the movie, the audio streams represent the main audio of the movie and the sub-audio to be mixed with the main audio , and the presentation graphics streams represent the movie's subtitles. The main video refers to the video images normally presented on a screen, where the sub-video refers to the video images (for example, text images explaining the movie review) that should be presented on a small screen inserted within of the video images. Interactive graphics streams represent an interactive presentation made up of GUI (graphical user interface) components presented on a screen.
<img file="MX385274B_D0154.tif" />
147
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Each stream included in the multiplexed data is identified by an identifier called PID exclusively assigned to the stream. For example, the video stream carrying the main video images of a movie is assigned 0x1011, each audio stream is assigned a different one from 0x1100 to OxlllF, each PG stream is assigned a different one from 0x1200 to 0xl21F, each IG stream is assigned a different one from 0x1400 to 0xl41F, each video stream carrying sub-video images from the movie is assigned a different one from OxlBOO to OxlBlF, each subaudio audio stream that is to be mixed with the main audio is assigned a different one from OxlAOO to OxlAlF.
Fig. 39 is a schematic diagram illustrating an example of the multiplexed data being multiplexed. First, a video stream 3 901, consisting of multiple video frames, and an audio stream 3904, consisting of multiple audio frames, are respectively converted into PES packet streams 3902 and 3905, then further converted into packets TS 3903 and 3906. Similarly, a current of 9<sup>r</sup>Presentation graphics 3911 and an interactive graphics stream 3914 are converted respectively to PES packet streams 3912 and 3915, then further converted to TS packets 3913 and 3916. Multiplexed data 3917 consists of TS packets 3903, 3906, 3913 and 3916 multiplexed into a single stream.
<img file="MX385274B_D0155.tif" />
148
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Figure 40 illustrates more details of a sequence of PES packets as contained in the video stream. The first row of Figure 40 shows a sequence of video frames from the video stream. The second row shows a sequence of PES packets. The arrows yyl, yy2, yy3 and yy4 indicate the multiple video display units, which are images I<sub>z</sub> B-pictures and P-pictures, in the video stream as split and individually stored as the payload of a PES packet. Each PES packet has a PES header. A PES header contains a PTS (presentation time) when the image should be presented, a DTS (decode time) when the image should be decoded, and so on.
Figure 41 illustrates the structure of a TS packet as it is ultimately recorded in the multiplexed data. A TS packet is a 188-byte fixed-length packet made up of a 4-byte PID identifying the stream and a 184-byte TS payload containing the data. The PES packets described above are individually partitioned and stored as the "TS" payload. For a BD-ROM, each TS packet has a 4-byte TP_Extra_Header attached to build a 192-byte source packet, which must be written as the multiplexed data. The TP_Extra_Header contains information such as an arrival time Arrival_Time_Stamp (ATS). The ATS indicates a time to start the transfer of the TS packet to the PID filter of a decoder. Multiplexed data consists of source packets
<img file="MX385274B_D0156.tif" />
149
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY communication is indicated in the lower row of figure 41. For each packet, an SPN (source packet number) increases, starting at the beginning of the multiplexed data.
In addition to video streams, audio streams, presentation graphics streams and the like, the TS packets included in the multiplexed data also comprise a PAT (Program Association Table), a PMT (Program Map Table ), a PCR (program time reference), etc. The PAT indicates the PID of a PMT used in the multiplexed data, and the PID of the PAT itself is recorded as 0. The PMT includes the PIDs that identify the respective streams, such as video, audio, and subtitles, contained in the multiplexed data, and attribute information (frame rate, aspect ratio, and the like) of the streams identified by the respective PIDs. In addition, the PMT includes various types of descriptors related to the multiplexed data. One such descriptor may be copy control information indicating whether or not the multiplexed data is allowed to be copied. The PCR includes information for synchronizing the ATC (arrival time) which serves as the time axis of the ATS to the STC (system time) which serves as the time axis of the PTS and the DTS. Each PCR packet includes an STC time corresponding to the ATS at which the packet should be transferred to the decoder.
Figure 42 illustrates the detailed configuration of
<img file="MX385274B_D0157.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
150 PMT data. The PMT starts with a PMT header indicating the length of the data contained in the PMT. After the PMT header, the descriptors relevant to the multiplexed data are arranged. An example of a descriptor included in the PMT is the copy control information described above. Following the descriptors, stream information relevant to the respective streams included in the "multiplexed" data is arranged. Each stream information element is composed of stream descriptors indicating a stream type that identifies a compression codec used for a corresponding stream, a PID for the stream, and attribute information (frame rate, aspect ratio, and so on). the style) of the stream. The PMT includes the same number of stream descriptors as the number of streams included in the multiplexed data.
When recorded on a recording medium or the like, the multiplexed data is recorded together with a multiplexed data information file.
Figure 43 illustrates an exemplary configuration for the multiplexed data information file. As shown, the multiplexed data information file is management information relating to the multiplexed data, it is provided in a one-to-one correspondence with the multiplexed data, and consists of the information about the multiplexed data, the attribute information of
<img file="MX385274B_D0158.tif" />
151
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY current and a map of entries.
The multiplexed data information consists of a system speed, a playback start time and a playback end time. The system rate indicates the maximum data transfer rate of the multiplexed data to the PID filter of a target decoder of the system described later. The multiplexed data includes the ATS at a set interval such that it does not exceed the speed of the system. The playback start time is set to the time specified by the PTS of the first video frame in the multiplexed data, where the playback end time is set to the time calculated by adding the playback duration of a frame to the PTS of the last video frame in the multiplexed data.
Figure 44 illustrates an exemplary configuration for the stream attribute information included in the multiplexed data information file. As shown, the stream attribute information is the attribute information of each stream included in the multiplexed data, recorded with respect to each PID. That is, different attribute information elements are provided for the different streams, ie for video streams, audio streams, presentation graphics streams and interactive graphics streams. The video stream attribute information indicates the compression codec
<img file="MX385274B_D0159.tif" />
152
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY used to compress the video stream, the resolution of the individual images that make up the video stream, the aspect ratio, the frame rate, etc. The audio stream attribute information indicates the compression codec used to compress the audio stream, the number of channels included in the audio stream, the language of the audio stream, the sample rate, and so on. This information is used to initialize the decoder prior to playback by a player.
In the present embodiment, the stream type included in the PMT is used among the information included in the multiplexed data. When the multiplexed data is recorded on a recording medium, the video stream attribute information included in the multiplexed data information file is used. Specifically, the video encoding method and device described in any of the foregoing embodiments may be modified to further include a step or unit for setting a specific information element in the type of stream included in the PMT or attribute information of the stream. video stream. The specific information element is to indicate that the video data is generated by the device and video encoding method described in the embodiment. According to such structure, the video data generated by the video encoding method and device described in any of the preceding embodiments is distinguishable from
153 video data that conforms to other standards.
Figure 45 illustrates an exemplary configuration of an audiovisual output device 4500 that includes a receiving device 4504 that receives a modulated signal that includes audio and video data transmitted by a broadcast station (base station) or data intended for broadcast. . The configuration of receiving device 4504 corresponds to receiving device 3700 in Figure 37. Audiovisual output device 4500 incorporates, for example, an OS (operating system) or incorporates a communications device 4506 to connect to the Internet (for example, a communications device intended for a wireless LAN or Ethernet™ ) . By itself, a video display unit 4501 can simultaneously display audio and video data, or video of broadcast video data 4502 and hypertext 4503 (from the World Wide Web) provided by the Internet. By operating a remote control 4507 (as an alternative to a mobile phone or keyboard), any of the video of the broadcast video data 4502 and hypertext 4503 provided by the Internet can be selected to switch operations. For example, when hypertext 4503 provided by the Internet is selected, the displayed website can be changed by remote control operations. When the audio and video data, or the video of the video data for broadcast 4502 is selected, the 4507 remote control can transmit the information of a selected channel
<img file="MX385274B_D0160.tif" />
154
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY (program. (television) or selected audio broadcast) . In this way, a 4505 interface obtains the information transmitted by the remote control. Receiver 4504 performs processing such as demodulation and error correction for the selected channel, thus obtaining the "received" data. At this point, the receiving device 4504 obtains the control symbol information including the information about the transmission scheme (as described using FIG. 5) of the control symbols included in the signal corresponding to the selected channel. By itself, the receive device 4504 can correctly set the receive operations, demodulation scheme, error correction scheme, etc. , thus enabling the data included in the data symbols transmitted by the broadcast station (base station) to be obtained. Although the preceding description is given for an example of the user using remote control 4507, the same operations apply when the user presses a selection key built into audiovisual output device 4500 to select a channel.
Furthermore, the audiovisual output device 4500 can be operated using the Internet. For example, the audiovisual output device 4500 can be made to record (store) a program through another terminal connected to the Internet. (Accordingly, audiovisual output device 4500 must include unit 3708 of FIG. 37). channel e select
<img file="MX385274B_D0161.tif" />
155
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY before starting the recording. In this way, the receiving device 4504 performs the processing, such as demodulation and error correction, corresponding to the selected channel, thus obtaining the received data. At this point, the receiving device 4504 obtains the control symbol information which includes the information about the transmission scheme (the transmission scheme, the modulation scheme, the error correction scheme, etc., from those previously described). modes) (as described using Figure 5) of the control symbols included in the signal corresponding to the selected channel. By itself, the receiving device 4 5 04 can correctly set the receiving operations, demodulation scheme, error correction scheme etc., thus making it possible to obtain the data included in the data symbols transmitted by the broadcasting station (base station).
Supplement
The present description considers a communications/broadcasting device such as a broadcasting station, a base station, an access point, a terminal, a mobile phone or the like provided with the transmitting device, and a communications device such such as a television, radio, terminal, personal computer, mobile phone, access point, base station or the like provided with the receiving device. The device of
<img file="MX385274B_D0162.tif" />
156
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY transmission and reception device relevant to the present invention are communication devices in a form suitable for executing applications, such as a television, radio, personal computer, mobile phone or the like, through the connection to some kind of interface (eg USB) .
Also, in the present embodiment, symbols other than data symbols, such as pilot symbols (i.e. preamble, single word, postamble, reference symbols, scattered pilot symbols, etc.), symbols intended for control information, etc. Although currently called pilot symbols and symbols intended for control information, such symbols may freely be called otherwise, since it is their function that remains and is considered important.
As long as a pilot symbol, for example, is a known symbol modulated with PSK modulation at the transmitter and receiver (alternatively, the receiver can be synchronized so that the receiver knows the symbols transmitted by the transmitter), the receiver can use that symbol for frequency synchronization, time synchronization, channel estimate (the CSI estimate of each modulated signal), signal detection and the like.
Symbols intended for control information are symbols that convey information (such as the scheme of
<img file="MX385274B_D0163.tif" />
157
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY modulation, the error correction coding scheme, the error correction code coding rate, and the adjustment information for the upper layer used in communications) that is transmitted to the receiving party in order to from executing non-data transmission (ie applications).
The present invention is not limited to the modes, but can also be embodied in various other ways. For example, while the foregoing embodiments describe communications devices, the present invention is not limited to such devices and may be implemented as software for a corresponding communications scheme.
Although the previously described embodiments describe phase change schemes for the transmission schemes of two modulated signals from two antennas, no limitation is foreseen in that sense. Precoding and a phase shift can be performed on four signals that have been correlated to generate four modulated signals transmitted using four antennas. That is, the present invention is applicable to performing a phase shift on N signals that have been correlated and precoded to generate N modulated signals transmitted using N antennas.
Although the previously described embodiments describe examples of systems where two modulated signals are transmitted from two antennas and received by two respective antennas in a MIMO communication system, the present
<img file="MX385274B_D0164.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
158 The invention is not so limited and is also applicable to MISO (multiple input, single output) communication systems. In a MISO system, the receiving device does not include the antenna 701_Y, the wireless unit 703_Y, the channel jitter estimator 707_l for the modulated signal zl, and the channel jitter estimator 707_2 for the modulated signal z2 in Figure 7 . However, the processing described in Mode 1 can still be performed to estimate rl and r2. The technology for receiving and decoding multiple signals transmitted simultaneously on a common frequency, and received by a single antenna, is well known. The present invention is an additional processing that supplements conventional technology for a signal processor that inverts a phase changed by the transmitter.
Although the present invention describes examples of systems where two modulated signals are transmitted from two antennas and received by two respective antennas in a MIMO communication system, the present invention is not so limited and is also applicable to MISO systems. In a MISO system, the transmitting device performs precoding and phase shifting so that the points described so far are applicable. However, the receiving device does not include the antenna 701_Y, the wireless unit 703_Y, the channel jitter estimator 7 07_l for the modulated signal zl, and the channel jitter estimator 707_2 for the signal
<img file="MX385274B_D0165.tif" />
159
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY modulated z2 of Figure 7. However, the processing set forth in the present description can still be executed to estimate the data transmitted by the transmission device. The technology for receiving and decoding multiple signals transmitted simultaneously on a common frequency, and received by a single antenna, is widely known (a single antenna receiver can apply ML (Max-log APP or similar) operations). The present invention can cause the signal processor 711 of FIG. 7 to perform the demodulation (detection) taking into account the precoding and phase shift, applied by the transmitter.
The present description uses terms such as precoding, precoding weights, precoding matrix, etc. The terminology itself may be different (for example, it may alternatively be called a codebook), since the key point of the present invention is the signal processing itself.
Also, although the present description explains the examples mainly using OFDM as the transmission scheme, the invention is not limited in that sense. Other multicarrier schemes than OFDM and single carrier schemes can be used to achieve similar modalities. Here, spread spectrum communications can also be used. When single carrier schemes are used, a phase shift with respect to the time domain is performed.
<img file="MX385274B_D0166.tif" />
160
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Furthermore, although the present description explains the use of the operations ML, APP, Max-log APP, ZF, MMSE etc. by the receiving device, those operations can all be generalized as waveform detection, demodulation, detection, estimation, and demultiplexing as the qualitative results (log-likelihood and log-likelihood ratio) and the quantitative results (zeroes and ones) thus obtained are the bits of individual data transmitted by the transmitting device.
Different data may be transmitted for each stream sl(t) and s2(t) (si(i), s2(i)) or identical data thereof.
The baseband signals of the two streams si (i) and s2(i) (where i indicates sequence (with respect to time or frequency (carrier) ) ) go through precoding and a regular phase shift (the order of the operations can be freely inverted) to generate two post-processing baseband signals zl(i) and z2(i). In the post-processing baseband signal zl(i), the in-phase component is leslj(i) while the quadrature component is Qi(i), and in the post-processing baseband signal z2(i), the in-phase component is Ii(i) while the quadrature component is Q<sub>2</sub>(Yo) . Baseband components may change, as long as the following is maintained.
Let be the in-phase component and quadrature component of the shifted baseband signal rl(i) Ii(i) and Q<sub>2</sub> (Yo) ,
<img file="MX385274B_D0167.tif" />
161
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY and be the in-phase component and the quadrature component of the shifted baseband signal r2 (i) I<sub>2</sub> (i) and Qi (i). The modulated signal corresponding to the shifted baseband signal rl(i) is transmitted by the transmit antenna 1 and the modulated signal corresponding to the shifted baseband signal r2(i) is transmitted from the transmit antenna 2, simultaneously in a common frequency. In this way, the modulated signal corresponding to the shifted baseband signal rl(i) and the modulated signal corresponding to the shifted baseband signal r2(i) are transmitted from different antennas simultaneously on a common frequency. As an alternative,
For the shifted baseband signal rl(i), the in-phase component may be Ii(i) while the quadrature component may be I<sub>2</sub> (i) , and for the switched baseband signal r2 (i), the in-phase component may be Qi(i) while the quadrature component may be Q<sub>2</sub> (Yo).
For the shifted baseband signal rl(i), the in-phase component can be I<sub>2</sub>(i) while the quadrature component may be Ii(i), and for the switched baseband signal r2(i), the in-phase component may be Qi (i) while the quadrature component may be Q<sub>2</sub>(Yo).
For the shifted baseband signal rl(i), the in-phase component may be Ii(i) while the quadrature component may be I<sub>2</sub> (i) , and for the shifted baseband signal r2(i), the in-phase component can be Q<sub>2</sub>(i) while the
<img file="MX385274B_D0168.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
162 quadrature component can be Qi(i) .
For the shifted baseband signal rl(i) , the in-phase component can be I<sub>2</sub>(i) while the quadrature component may be Ii(i), and for the shifted baseband signal r2(i), the in-phase component may be Q<sub>2</sub>(i) while the quadrature component can be Qi(i) .
For the shifted baseband signal rl(i), the in-phase component can be T<sub>x</sub>(i) while the quadrature component can be Q<sub>2</sub> (i) , and for the switched baseband signal r2(i), the in-phase component may be Qi(i) while the quadrature component may be I<sub>2</sub>(Yo) .
For the shifted baseband signal rl(i), the in-phase component can be Q<sub>2</sub>(i) while the quadrature component may be Ii(i), and for the shifted baseband signal r2(i), the in-phase component may be I<sub>2</sub>(i) while the quadrature component can be Qi(i).
For the shifted baseband signal rl(i), the in-phase component can be Q<sub>2</sub> (i) while the quadrature component may be Ii(i) , and for the shifted baseband signal r2(i) , the in-phase component may be Qi(i) while the quadrature component may be I<sub>2</sub>(Yo) .
For the shifted baseband signal r2(i), the in-phase component may be Ii(i) while the quadrature component may be I<sub>2</sub> (i) , and for the changed baseband signal rl(i), the in-phase component can be Qi(i) while the
<img file="MX385274B_D0169.tif" />
163
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY quadrature component can be Q<sub>2</sub>(Yo) .
• For the shifted baseband signal r2(i), the in-phase component can be 12(1) while the quadrature component can be Ii(i), and for the shifted baseband signal rl(i), the in-phase component may be Qi(i) while the quadrature component may be Q<sub>2</sub> (Yo) .
• For the shifted baseband signal r2(i), the in-phase component can be Ιχ (i) while the quadrature component can be I<sub>2</sub>(i) , and for the shifted baseband signal rl(i), the in-phase component can be Q<sub>2</sub> (i) while the quadrature component can be Qi(i).
For the shifted baseband signal r2(i), the in-phase component can be I<sub>2</sub>(i) while the quadrature component may be Ii(i), and for the shifted baseband signal rl(i), the in-phase component may be Q<sub>2</sub>(i) while the quadrature component can be Qi(i).
For the shifted baseband signal r2(i), the in-phase component may be Ii(i) while the quadrature component may be Q<sub>2</sub> (i) , and for the shifted baseband signal rl(i), the in-phase component can be I<sub>2</sub>(i) while the quadrature component can be Qi(i) .
For the shifted baseband signal r2(i), the in-phase component may be Ii(i) while the quadrature component may be Q<sub>2</sub>(i) , and for the changed baseband signal rl(i), the in-phase component can be Qi(i) while the
<img file="MX385274B_D0170.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
164 quadrature component can be 12(1).
For the shifted baseband signal r2(i), the in-phase component can be Q<sub>2</sub>(i) while the quadrature component may be Ii(i), and for the shifted baseband signal rl(i), the in-phase component may be I<sub>2</sub>(i) while the quadrature component can be Qi(i).
For the shifted baseband signal r2(i), the in-phase component can be Q<sub>2</sub>(i) while the quadrature component may be Ii(i), and for the switched baseband signal rl(i), the in-phase component may be Qi(i) while the quadrature component may be I<sub>2</sub> (Yo) . Alternatively, although the foregoing description explains the mode of two types of signal processing on the signals of both streams so as to change the in-phase component and the quadrature component of the two signals, the invention is not limited in that sense. The two types of signal processing can be performed on more than two streams, such as to change the in-phase component and quadrature component of them.
Alternatively, although the preceding examples describe the changing of baseband signals having a common timestamp (frequency (sub-)carrier), the changing baseband signals need not necessarily have a common timestamp . For example, any of the following are possible.
• For the changed baseband signal rl(i), the
<img file="MX385274B_D0171.tif" />
165
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY component in phase can be I^i+v) while the quadrature component can be Q<sub>2</sub>(i+w) , and for the shifted baseband signal r2(i) , the in-phase component may be I<sub>2</sub>(i+w) while the quadrature component can be Qi(i+v).
• For the switched baseband signal rl(i), the in-phase component can be Ii(i+v) while the quadrature component can be I<sub>2</sub>(i+w), and for the shifted baseband signal r2(i), the in-phase component may be Qi(i+v) while the quadrature component may be Q<sub>2</sub>(i+w).
For the shifted baseband signal rl(i), the in-phase component can be I<sub>2</sub>(i+w) while the quadrature component can be I<sub>x</sub>(i+v), and for the switched baseband signal r2(i), the in-phase component may be Qi(i+v) while the quadrature component may be Q<sub>2</sub>(i+w).
For the shifted baseband signal rl(i), the in-phase component may be Ii(i+v) while the quadrature component may be I<sub>2</sub>(i+w), and for the shifted baseband signal r2(i), the in-phase component can be Q<sub>2</sub>(i+w) while the quadrature component can be Qi(i+v).
For the shifted baseband signal rl(i), the in-phase component can be I<sub>2</sub>(i+w) while the quadrature component may be Iji+v), and for the shifted baseband signal r2(i), the in-phase component may be Q<sub>2</sub>(i+w) while the quadrature component can be Qi(i+v).
For the changed baseband signal rl(i) , the
<img file="MX385274B_D0172.tif" />
166
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY component in phase can be Iji+v) while the quadrature component can be Q<sub>2</sub>(i+w) , and for the shifted baseband signal r2(i) , the in-phase component can be Q<sub>x</sub>(i+v) while the quadrature component can be I<sub>2</sub>(i+w).
• For the shifted baseband signal rl(i), the in-phase component can be Q<sub>2</sub>(i+w) while the quadrature component may be Ii(i+v) , and for the shifted baseband signal r2(i) , the in-phase component may be I<sub>2</sub>(i+w) while the quadrature component can be Qi(i+v).
• For the shifted baseband signal rl(i), the in-phase component can be Q<sub>2</sub>(i+w) while the quadrature component may be IJi+v), and for the shifted baseband signal r2(i) , the in-phase component may be Qi(i+v) while the quadrature component quadrature can be I<sub>2</sub>(i+w).
For the shifted baseband signal r2(i), the in-phase component can be I<sub>x</sub>(i+v) while the quadrature component can be I<sub>2</sub>(i+w), and for the switched baseband signal rl(i), the in-phase component may be Qi(i+v) while the quadrature component may be Q<sub>2</sub>(i+w).
For the shifted baseband signal r2(i), the in-phase component can be I<sub>2</sub>(i+w) while the quadrature component may be Ii(i+v), and for the shifted baseband signal rl(i), the in-phase component may be Q<sub>x</sub>(i+v) while the quadrature component can be Q<sub>2</sub>(i+w).
For the changed baseband signal r2(i), the
<img file="MX385274B_D0173.tif" />
167
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY component in phase can be Ixd+v) while the quadrature component can be I<sub>2</sub>(i+w), and for the shifted baseband signal rl(i) , the in-phase component can be Q<sub>2</sub> (i+w) while the quadrature component can be Qi(i+v).
For the shifted baseband signal r2(i), the in-phase component can be I<sub>2</sub>(i+w) while the quadrature component may be Ii(i+v), and for the shifted baseband signal rl(i), the in-phase component may be Q<sub>2</sub>(i+w) while the quadrature component can be Qi(i+v).
For the shifted baseband signal r2(i), the in-phase component may be Ii(i+v) while the quadrature component may be Q<sub>2</sub>(i+w), and for the shifted baseband signal rl(i), the in-phase component can be I<sub>2</sub>(i+w) while the quadrature component can be Qi(i+v).
For the shifted baseband signal r2(i), the in-phase component may be liii+v) while the quadrature component may be Q<sub>2</sub>(i+w), and for the switched baseband signal rl(i) , the in-phase component may be Qi(i+v) while the quadrature component may be I<sub>2</sub>(i+w).
For the shifted baseband signal r2(i), the in-phase component can be Q<sub>2</sub>(i+w) while the quadrature component may be Ihfi+v), and for the shifted baseband signal rl(i) , the in-phase component may be I<sub>2</sub>(i+w) while the quadrature component can be Qi(i+v).
For the changed baseband signal r2(i), the
<img file="MX385274B_D0174.tif" />
168
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY component in phase can be Q<sub>2</sub>(i+w) while the quadrature component may be Iji+v), and for the shifted baseband signal rl(i), the in-phase component may be Q<sub>x</sub>(i+v) while the quadrature component can be I<sub>2</sub>(i+w).
Figure 5-5 illustrates a baseband signal changer 5502 explaining the above. As shown, of the two processed baseband signals zl(i) 5501_l and z2(i) 5501_2, the processed baseband signal zl(i) 5501_l has the in-phase component Ii(i) and the quadrature component Qi( i), while the processed baseband signal z2 (i) 5501^2 has the phase I component<sub>2</sub>(i) and the quadrature component Q<sub>2</sub>(Yo) . So, after the change, changed baseband signal rl (i) 5503_l has the component in phase I<sub>r</sub>i(i) and the quadrature component Q<sub>r</sub>i(i) , while the changed baseband signal r2 (i) 5503_2 has the in-phase component I<sub>r2</sub>(i) and the quadrature component Q<sub>r2</sub>(Yo) . The phase I component<sub>r</sub>i(i) and the quadrature component Q<sub>r</sub>i(i) of the shifted baseband signal rl(i) 5503_l and the in-phase component Ir2(i) and the quadrature component Q<sub>r2</sub>(i) of the changed baseband signal r2(i) 5503_2 can be expressed as any of the foregoing. Although this example describes the change made to baseband signals that have a common date-time (common ((sub-)carrier) frequency) and have undergone two types of signal processing, the same can be applied to baseband signals. baseband devices that have gone through two types of signal processing but have different indicators
<img file="MX385274B_D0175.tif" />
169
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY date-time (different frequencies ((sub-)carrier)).
Each of the transmission antennas of the transmission device and each of the reception antennas of the reception device shown in the figures may be formed by multiple antennas.
The present description uses the symbol V, which is the universal quantifier, and the symbol 3, which is the existential quantifier.
Also, the present description uses the radian as the phase unit in the complex plane, for example, for the argument thereof.
When dealing with the complex plane, the coordinates of the complex numbers can be expressed as polar coordinates. For a complex number z = a + jb (where 15 a and b are real numbers and j is the imaginary unit), the corresponding point (a, b) in the complex plane is expressed by the polar coordinates [r, Θ], converted as follows: a = rx cos9 b = rx sin9
[Mathematics 49] (formula 49) r = 4aAA where r is the absolute value of z (r = |z|) , and Θ is the argument of it. Thus, z = a + jb can be expressed
<img file="MX385274B_D0176.tif" />
170
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY as a re<sup>jS</sup>.
In the present invention, the baseband signals si, s2, zl, and z2 are described as complex signals. A complex signal consisting of the in-phase signal I and the quadrature signal Q can also be expressed as the complex signal I + jQ. Here, any of I and Q can be equal to zero.
Figure 46 illustrates an exemplary diffusion system using the phase change scheme set forth in the present description. As shown, a 4601 video encoder takes video as input, performs video encoding, and outputs 4602 encoded video data. An audio encoder takes audio as input, performs audio encoding, and outputs 4602 encoded video data. encoded audio data 4604 . A 4605 data encoder takes data as input, performs data encoding (for example, data compression), and outputs the 4606 encoded data. Taken together, these components form a 4600 source information encoder.
A transmitter 4607 takes the encoded video data 4602, the encoded audio data 4604, and the encoded data 4606 as input, performs error correction encoding, modulation, precoding, and phase shift (e.g., processing). of signals by the transmission device of figure 3) in a subset or in all of them, and outputs the transmission signals 4608_l
<img file="MX385274B_D0177.tif" />
171
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY a 4608_N. The transmission signals 4608_l to 4608_N are then transmitted by the antennas 4609_l to 4609_N as radio waves.
A receiver 4612 takes the received signals 4611_1 to 4611_M received by the antennas 4610_l to 4610_M as input, performs processing such as frequency conversion, phase shift, precoding decoding, log-likelihood ratio calculation and error correction decoding (for example, processing by the receiving device of Figure 7), and outputs the received data 4613, 4615, and 4617. A source information decoder 4619 takes the received data 4613, 4615 and 4617 as input. A video decoder 4614 takes received data 4613 as input, performs video decoding, and outputs a video signal. The video is then shown on a television screen. An audio decoder 4616 takes the received data 4615 as input. Audio decoder 4616 performs audio decoding and outputs an audio signal. The audio is then played through the speakers. A data decoder 4618 takes the received data 4617 as input, performs data decoding, and outputs information.
In the above-described embodiments relevant to the present invention, the number of encoders in the transmission device using a multi-carrier transmission scheme such as OFDM may be any, such as
172 already described. Therefore, as in Fig. 4, for example, the transmission device may have only one encoder and apply a scheme for distributing the output to multi-carrier transmission scheme, such as OFDM. In such circumstances, the wireless units 310A and 310B of Figure 4 should replace the OFDM-related processors 1301A and 1301B of Figure 12. The description of the OFDM-related processors is as given in Mode 1.
Although Modality 1 gives Math 36 (formula
36) as an example of a precoding matrix, another precoding matrix can also be used, when the following scheme is applied.
[Mathematics 50] (formula 50) íwll wl2>
ax l<sup>w21</sup> w22j (axe
In the Math (Formula 36) and Math 50 (Formula 50) precoding matrices, the value of □ 20 is set as given by Math 37 (Formula 37) and Math 38 (Formula 38). However, no limitation is foreseen in this regard. A simple precoding matrix can be obtained by setting oc = 1, which is also a valid value.
In Mode Al, the phase shifters of the
<img file="MX385274B_D0178.tif" />
173
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY figures 3, 4, 6, 12, 25, 29, 51 and 53 are indicated as having a phase change value of PHASE [i] (where i = 0, 1, 2 ... N -2, Nl, that is, O^i^Nl, i being an integer) to achieve a period (cycle) of N (value reached in the case that figures 3, 4, 6, 12, 25, 29, 51 and 53 perform a phase shift on only one baseband signal). The present description explains performing a phase shift on a precoded baseband signal (ie in Figures 3, 4, 6, 12, 25, 29 and 51), ie on the precoded baseband signal z2'. Here, PHASE [k] is calculated as follows.
[Mathematics 51] (formula 51)
go jr
PHASE [£] = TV radians where k = 0, 1, 2... N-2, Nl. When N = 5, 7, 9, 11 or 15, the receiving device can obtain a good data receiving quality.
Although the present description explains the details of phase shift schemes involving two modulated signals transmitted by multiple antennas, no limitation is intended in that regard. Precoding and a phase shift may be performed on three or more baseband signals on which correlation has been performed according to a modulation scheme, followed by predetermined processing on the postphase shifted baseband signals.
<img file="MX385274B_D0179.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
174 and transmission using multiple antennas, to achieve the same results.
Programs for executing the above transmission scheme can be stored, eg . , in advance in ROM (read-only memory) and be read for operation by a CPU.
Also, the programs for executing the foregoing transmission scheme may be stored on a computer-readable recording medium, the programs stored on the recording medium may be loaded into the computer's RAM (random access memory), and the computer can work according to the programs.
The components of the foregoing described embodiments may typically be assembled as an LSI (Large Scale Integration), a type of integrated circuit. The individual components may respectively be made on discrete chips, or a subset or all of the components may be made on a single chip. Although an LSI has been mentioned before, the terms IC, system LSI, super LSI, or ultra LSI may also apply, depending on the degree of integration. Also, the method for assembling the integrated circuit is not limited to LSI. A dedicated circuit or a general purpose processor may be used. After mounting the LSI, an FPGA (Programmable Gate Array) or a reconfigurable processor can be used.
<img file="MX385274B_D0180.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
175
Also, should progress in the field of semiconductors or emerging technologies lead to the replacement of LSI by other integrated circuit methods, such technology can of course be used to integrate the functional blocks. Biotechnology applications are also plausible.
Cl mode
Mode 1 explained that the precoding matrix in use can be changed when transmission parameters change. The present embodiment describes a detailed example of such a case, where as already described (in the supplement), the transmission parameters change such that the currents sl(t) and s2(t) change between the transmission of different data and transmission of identical data, and therefore change the precoding matrix and phase shift in use.
The example of the present embodiment describes a situation where two modulated signals transmitted from two different transmit antennas alternate between having the modulated signals include identical data and having the modulated signals each include different data.
Figure 56 illustrates an exemplary configuration of a transmission device that switches between transmission schemes, as already described. In figure 56, the components that operate in the manner described in figure
<img file="MX385274B_D0181.tif" />
176
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY use identical reference numbers. As shown, Figure 56 differs from Figure 54 in that a distributor 4 04 takes the framing signal 313 as input. The operations of distributor 404 are described using Fig.
57.
Figure 57 illustrates the operations of distributor 404 when transmitting identical data and when transmitting different data. As shown, given the encoded data xl, x2, x3, x4, x5, x6, etc., when identical data is transmitted, the distributed data 405A is given as xl, x2, x3, x4, x5, x6, etc. ., while distributed data 405B is similarly given as xl, x2, x3, x4, x5, x6, etc.
On the other hand, when different data is transmitted, distributed data 405A is given as xl, x3, x5, x7, x9, etc., while distributed data 405B is given as x2, x4, x6, x8, xlO , etc.
The dispatcher 404 determines, according to the input framing signal 313, whether the transmission mode is transmission of identical data or transmission of different data.
An alternative to the above is shown in Figure 58. As shown, when transmitting identical data, distributor 404 outputs distributed data 405A as xl, x2, x3, x4, x5, x6, etc., while it doesn't output anything like 405B distributed data. Therefore, when the signal
<img file="MX385274B_D0182.tif" />
177
IMPI
The frame configuration 313 indicates the transmission of identical data, the distributor 404 operates as already described, while the interpolator 304B and the correlator 306B of figure 56 do not operate. Thus, only the baseband signal 307A outputted by mapper 306A of FIG. 56 is valid, and is taken as input by both weighting units 308A and 308B.
A characteristic feature of the present embodiment is that when the transmission mode changes from transmission of identical data to transmission of different data, the precoding matrix may also change. As indicated by Math 36 (formula 36) and Math 39 (formula 39) in mode 1, given a matrix consisting of wll, W12, w21 and w22, the precoding matrix, used to transmit identical data can be such as follow.
[Math 52] (formula 52) ^wll Μ2Ί (a (P 1^21 w22 J 1^0 CL;
where a is a real number (a can also be a complex number, but since the baseband signal being input as a result of precoding goes through a phase shift, a real number is preferred for considerations of circuit size and complexity reduction). Also, when a is equal to one, the weight units 308A and 308B do not
<img file="MX385274B_D0183.tif" />
178
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY perform the weighting and output the input signal as it is.
Therefore, when identical data is transmitted, the baseband weighted signals 309A and 316B output by the weighting units 308A and 308B are identical signals.
When the framing signal indicates identical transmission mode, the phase shifter 5201 performs a phase shift on the weighted baseband signal 309A and outputs the postphase shifted baseband signal 52 02 . Similarly, when the framing signal indicates identical transmission mode, the phase shifter 317B performs a phase shift on the weighted baseband signal 316B and outputs the postphase shifted baseband signal 3 09B. The phase shift performed by the 5201 phase shifter is e<sup>jA<t)</sup> (alternatively, and<sup>jA<f)</sup> hey<sup>jA(t,f)</sup>) (where t is the time and f is the frequency) (therefore e<sup>jA(t)</sup> (alternatively, and<sup>jA(f)</sup> or ejA(t,f)}<sub>it is</sub> θι<sub>goes</sub>Yo<sub>or</sub> by which the input baseband signal is multiplied), and the phase shift performed by phase shifter 317B is ejB(t) (alternatively, e<sup>jB(f)</sup> hey<sup>jB(t,f></sup>) (where t is the time and f is the frequency) (therefore e<sup>28</sup>^<sup>1</sup> (alternatively, and<sup>2</sup>®<sup>11</sup>* o is the value by which the input baseband signal is multiplied) . Thus, the following condition is satisfied.
<img file="MX385274B_D0184.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
179
[Mathematics 53] (formula 53) Some time t meets (O, some (carrier) frequency f meets (O, some (carrier) frequency f and time t meet
By itself, the transmission signal can reduce the multipath influence and thus improve the data reception quality for the receiving device. (However, the phase shift can also be performed by just one of the baseband weighted signals 309A and 316B).
In Fig. 56, when OFDM is used, processing, such as IFFT and frequency conversion, is performed on the post-phase shifted baseband signal 5202, and the result is transmitted by a transmit antenna. (See Fig. 13) (Consequently, the post-phase shifted baseband signal 52 02 can be considered the same as signal 1301A in Fig. 13). Similarly, when OFDM is used, processing, such as IFFT and frequency conversion, is performed on the post-phase shifted baseband signal 309B, and the result is transmitted by a transmit antenna. (See Fig. 13) (Consequently, the post-phase shifted baseband signal 3 09B can be considered the same as the signal 1301B of Fig. 13).
<img file="MX385274B_D0185.tif" />
180
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
When the selected transmission mode indicates transmission of different data, any of Math 36 (Formula 36), Math 39 (Formula 39), and Math 50 (Formula 50) given in mode 1 can be applied. Significantly, phase shifters 5201 and 317B of FIG. 56 use a different phase shift scheme than when transmitting identical data. Specifically, as described in mode 1, for example, phase shifter 5201 performs the phase shift while phase shifter 317B does not, or phase shifter 317B performs the phase shift while the 5201 phase shifter does not. Only one of the two phase shifters performs the phase shift. In this way, the receiving device obtains good data reception quality in the LOS environment as well as the NLOS environment.
When the selected transmission mode indicates the transmission of different data, the precoding matrix may be as given in Math 52 (formula 52) or as given in any of Math 36 (formula 36), Math 50 (formula 50) and Math 39 (formula 39) or it can be a precoding matrix different from the one given in Math 52 (formula 52). In this way, the receiving device is especially likely to experience improvements in data reception quality in the LOS environment.
Also, although the present embodiment explains examples using OFDM as the transmission scheme, the invention
<img file="MX385274B_D0186.tif" />
181
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY is not limited in that sense. Multi-carrier schemes other than OFDM and single-carrier schemes can be used to achieve similar modalities. Here, spread spectrum communications can also be used. When single carrier schemes are used, the phase change is done with respect to the time domain.
As explained in Mode 3, when the transmission scheme involves the transmission of different data, the phase change is performed only on the data symbols. However, as described in the present embodiment, when the transmission scheme involves transmission of identical data, the phase change need not be limited to the data symbols, but can also be performed on the pilot symbols, control and other such symbols inserted in the transmission frame of the transmission signal. (Phase shifting need not always be performed on symbols such as pilot symbols and control symbols, although doing so is preferred in order to achieve diversity gain).
C2 modality
The present embodiment describes a configuration scheme for a base station corresponding to the CI mode.
Figure 59 illustrates the relationship of base stations (broadcast stations) to terminals. A terminal P (5907) receives the transmission signal 5903A transmitted by the
<img file="MX385274B_D0187.tif" />
182
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY antenna 5904A and the transmission signal 5905A transmitted by the antenna 5906A of broadcasting station A (5902A), then performs the predetermined processing on them to obtain the received data.
A terminal Q (5908) receives the transmission signal 5903A transmitted by the antenna 5904A of base station A (5902A) and the transmission signal 593B transmitted by the antenna 5904B of base station B (5902B), then performs in them the default processing to obtain the received data.
Figures 60 and 61 illustrate Base Station A's (5902A) frequency assignment for transmit signals 5903A and 5905A transmitted by antennas 5904A and 5906A, and Base Station B's (5902B) frequency assignment for the 5903B and 5905B transmit signals transmitted by the 5904B and 5906B antennas. In figures 60 and 61, the frequency is on the horizontal axis and the transmission power is on the vertical axis.
As shown, transmit signals 5903A and 5905A transmitted by base station A (5902A) and transmit signals 5903B and 5905B transmitted by base station B (5902B) use at least frequency band X and frequency band X. frequency band Y. Frequency band X is used to transmit data of a first channel, and frequency band Y is used to transmit data of a second channel.
Therefore, the P terminal (5907) receives the signal
<img file="MX385274B_D0188.tif" />
183
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY transmission signal 5903A transmitted by antenna 5904A and transmission signal 5905A transmitted by antenna 5906A of base station A (5902A), extracts frequency band X from them, performs the predetermined processing and this way it obtains the data of the first channel. Terminal Q (5908) receives transmit signal 5903A transmitted by antenna 5904A of base station A (5902A) and transmit signal 5903B transmitted by antenna 5904B of base station Β (5902B), extracts from them frequency band Y, performs the predetermined processing and thus obtains the data of the second channel.
The following describes the setup and operations of Base Station A (5902A) and Base Station Β (5902B).
As described in mode Cl, both base station A (5902A) and base station Β (5902B) incorporate a transmission device configured as shown in Figures 56 and 13. When transmitting as shown in Figure 60, base station A (5902A) generates two different modulated signals (in which precoding and a phase shift are performed) with respect to frequency band X, as described in mode Cl. The two modulated signals are respectively transmitted by antennas 5904A and 5906A. With respect to frequency band Y, base station A (5902A) operates interpolator 304A, correlator 306A, weighting unit 308A, and phase shifter of Figure 56 to generate
<img file="MX385274B_D0189.tif" />
184
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY the modulated signal 5202. Then, a transmission signal corresponding to the modulated signal 52 02 is transmitted by the antenna 1310A of Figure 13, that is, by the antenna 5904A of Figure 59. Similarly , base station Β (5902B) operates interpolator 304A, correlator 306A, weighting unit 308A, and phase shifter 52 01 of FIG. 56 to generate modulated signal 5202. Then, a transmission signal corresponding to the modulated signal 5202 is transmitted by the antenna 1310A of Fig. 13, that is, by the antenna 5904B of Fig. 59.
The creation of encrypted data in frequency band Y may involve, as shown in Fig. 56, generating the encrypted data at the individual base stations. Or, it may involve causing one of the base stations to generate such encrypted data for transmission to other base stations. As an alternative scheme, one of the base stations may generate the modulated signals and be configured to pass the modulated signals so generated to other base stations.
Also, in FIG. 59, signal 5901 includes information pertaining to the mode of transmission (transmission of identical data or transmission of different data). The base stations get this signal and so switch between the generation schemes for the modulated signals in each frequency band. Here, signal 5901 is indicated in figure 59 as
<img file="MX385274B_D0190.tif" />
185
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY input from another device or from a network. However, configurations are also possible where, for example, base station A (5902) is a master base station passing a signal corresponding to signal 5901 to base station
B(5902B).
As already explained, when the base station transmits different data, the precoding matrix and phase shift scheme are set according to the transmission scheme to generate the modulated signals.
On the other hand, to transmit identical data, two base stations respectively generate and transmit modulated transmission signals. In such circumstances, the base stations each generating modulated signals for transmission from a common antenna can be considered as two combined base stations using the precoding matrix given by Math 52 (formula 52). The phase change scheme is as explained in the CI mode, for example, and meets the conditions of Math 53 (formula 53).
Also, the transmission scheme of frequency band X and frequency band Y may vary in time. Therefore, as illustrated in Figure 61, as time passes, the frequency assignment changes from what is indicated in Figure 60 to what is indicated in Figure 61.
According to the present embodiment, not only can
<img file="MX385274B_D0191.tif" />
186
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY obtain the receiving device improved data reception quality for the transmission of identical data as well as the transmission of different data, but also the transmission devices can share a phase shifter.
Also, although the present embodiment explains examples using OFDM as the transmission scheme, the invention is not limited in that sense. Multi-carrier schemes other than OFDM and single-carrier schemes can be used to achieve similar modalities. Here, spread spectrum communications can also be used. When single carrier schemes are used, the phase change is done with respect to the time domain.
As explained in mode 3, when the transmission scheme involves the transmission of different data, the phase change is performed only on the data symbols. However, as described in the present embodiment, when the transmission scheme involves transmission of identical data, the phase change need not be limited to data symbols, but can also be performed on pilot symbols, control and other such symbols inserted in the transmission frame of the transmission signal. (Phase shifting need not always be performed on symbols such as pilot symbols and control symbols, although doing so is preferred in order to achieve diversity gain).
<img file="MX385274B_D0192.tif" />
187
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
C3 modality
The present embodiment describes a configuration scheme for a repeater corresponding to mode Cl. The repeater may also be called a repeater station.
Figure 62 illustrates the relationship of base stations (broadcast stations) with repeaters and terminals. As shown in FIG. 63, base station 6201 at least transmits modulated signals in frequency band X and frequency band Y. Base station 6201 transmits the respective modulated signals on antenna 6202A and antenna 6202B. The transmission scheme used here is described below, with reference to figure 63.
Repeater A (6203A) performs processing, such as demodulation, on the received signal 6205A that is received by the receive antenna 6204<sup>a</sup>, and in the received signal 6207A that receives the receiving antenna 6206A, thus obtaining the received data. Then, in order to transmit the received data to a terminal, repeater A (6203A) performs transmission processing to generate modulated signals 6209A and 6211A for transmission at respective antennas 6210A and 6212A.
Similarly, repeater B (6203B) performs processing, such as demodulation, on the received signal 6205B received by receive antenna 6204B, and on the received signal 6207B received by receive antenna 6206B, thus obtaining the data received. Then, in order to transmit the data
<img file="MX385274B_D0193.tif" />
188
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY received at a terminal, the repeater B (6203B) performs the transmission processing to generate the modulated signals 6209B and 6211B for the purpose of transmission in the respective antennas 6210B and 6212B. Here, repeater B (6203B) is a master repeater that outputs a control signal 6208. Repeater A (6203A) takes the control signal as input. A master repeater is not strictly necessary. Base station 6201 may also transmit individual control signals to repeater A (6203A) and repeater B (6203B).
Terminal P (5907) receives the modulated signals transmitted by repeater A (6203A), thus obtaining the data. Terminal Q (5908) receives the signals transmitted by repeater A (6203A) and repeater B (6203B), thus obtaining the data. Terminal R (6213) receives the modulated signals transmitted by repeater B (6203B), thus obtaining the data.
Figure 63 illustrates the frequency allocation for a modulated signal transmitted by antenna 6202A between the transmit signals transmitted by the base station, and the frequency allocation of modulated signals transmitted by antenna 6202B. In figure 63, the frequency is on the horizontal axis and the transmit power is on the vertical axis.
As shown, the modulated signals transmitted by antenna 6202A and antenna 6202B use at
<img file="MX385274B_D0194.tif" />
189
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY minus frequency band X and frequency band Y. Frequency band X is used to transmit the data of a first channel, and frequency band Y is used to transmit the data of a second channel.
As described in the Cl mode, the data of the first channel is transmitted using the frequency band X in the different data transmission mode. Therefore, as shown in Figure 63, the modulated signals transmitted by antenna 6202A and by antenna 62 02B include the components of frequency band X. Those components of frequency band X are received by repeater A and by repeater B. Therefore, as described in mode 1 and mode Cl, the modulated signals in frequency band X are signals on which correlation has been performed, and to which precoding (weighting) and shifting are applied. phase.
As shown in Figure 62, the second channel data is transmitted by antenna 6202A of Figure 2 and transmitted in the components of frequency band Y. Those components of frequency band Y are received by repeater A. and by repeater B.
Figure 64 illustrates the frequency assignment for the transmit signals transmitted by repeater A and repeater B, specifically for the 6209A modulated signal transmitted by the 6210A antenna and the 6211A modulated signal.
<img file="MX385274B_D0195.tif" />
190
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY transmitted by antenna 6212A of repeater 6210Ά, and for the modulated signal 6209B transmitted by antenna 6210B and the modulated signal 6211B transmitted by antenna 6212B of repeater B. In figure 64, the frequency is on the horizontal axis and transmit power is on the vertical axis.
As shown, the 6209A modulated signal transmitted by the 6210A antenna and the 6211A modulated signal transmitted by the 6212A antenna use at least frequency band X and frequency band Y. In addition, the 6209B modulated signal transmitted by the antenna 6210B and the 6211B modulated signal transmitted by the 6212B antenna similarly use at least the X frequency band and the Y frequency band. Frequency band X is used to transmit data from a first channel, and frequency band Y is used to transmit data from a second channel.
As described in the Cl mode, the data of the first channel is transmitted using the frequency band X in different data transmission mode. Therefore, as shown in Figure 64, the 6209A modulated signal transmitted by the 6210A antenna and the 6211A modulated signal transmitted by the 6212B antenna include the X frequency band components. Those X frequency band components are received by terminal P. Similarly, as shown in Figure 64, the 6209B modulated signal transmitted by the 6210B antenna and the 6211B modulated signal transmitted by the 6212B antenna include the
<img file="MX385274B_D0196.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
191 components of frequency band X. Those components of frequency band X are received by terminal R. Therefore, as described in mode 1 and mode Cl, the modulated signals in frequency band X are signals where correlation has been performed, and where precoding (weighting) and phase shifting are applied.
As shown in Figure 64, the second channel data is carried by the modulated signals transmitted by repeater A antenna 6210A (6203A) and repeater B antenna 6210B (6203) of Figure 62 and the Data is transmitted in the Y frequency band components. Here, the components of frequency band Y in the 6209A modulated signal transmitted by repeater A's 6210A antenna (6203A) and those of the 6209B modulated signal transmitted by repeater B's 6210B antenna (6203B) are used in a transmission mode involving transmission of identical data, communication o is explained in Cl mode. Those components of frequency band Y are received by terminal Q.
The following describes the configuration of Repeater A (6203A) and Repeater B (6203B) in Figure 62, with reference to Figure 65.
Figure 65 illustrates an exemplary configuration of a receiver and transmitter in a repeater. Components that operate identically to those in Figure 56 use the same reference numbers. The 62 03X receiver takes the signal
<img file="MX385274B_D0197.tif" />
192
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY Received signal 6502A that receives the receiving antenna 6501A and the received signal 6502B that receives the receiving antenna 6501B as input, performs signal processing (demultiplexing or signal composition, error correction decoding, etc.) . In the X frequency band components thereof to obtain the data 6204X transmitted by the base station using the X frequency band, it outputs the data to the distributor 404 and obtains the transmission scheme information included in the information control (and transmission pattern information when transmitted by a repeater), and outputs frame configuration signal 313.
The 6203X receiver and onwards constitute a processor for generating a modulated signal that transmits the X frequency band. Furthermore, the receiver described here is not only the receiver for the X frequency band, as shown in figure 65, but also it also incorporates receivers for other frequency bands. Each receiver forms a processor to generate the modulated signals that transmit a respective frequency band.
The overall operations of dispatcher 404 are identical to those of the base station dispatcher described in mode C2.
When transmitting as indicated in figure 64, repeater A (6203A) and repeater Β (6203B) generate two different modulated signals (in which the
<img file="MX385274B_D0198.tif" />
193
IMPI
MEXICAN INSTITUTE OF PROPERTY OR INDUSTRIAL (MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY) in frequency band X as described in Mode Cl. The two modulated signals are transmitted respectively by antennas 6210A and 6212A of repeater A (6203) in figure 62 and by the antennas 6210B and 6212B of the repeater Β (6203B) of figure 62.
For frequency band Y, repeater A (6203A) operates a processor 6500 relevant to frequency band Y and corresponding to the signal processor 6500 relevant to frequency band X shown in Figure 65 (the signal processor 6500 is the signal processor relevant to frequency band X, but since an identical signal processor is incorporated for frequency band Y, this description uses the same reference numerals), interpolator 304A, correlator 306A, weighting unit 308A, and phase shifter 5201 to generate modulated signal 5202 . A transmit signal corresponding to modulated signal 5202 is then transmitted by antenna 1301A of FIG. 13, ie, by antenna 6210A of FIG. 62 . Similarly, repeater B (6203 B) operates interpolator 304A, correlator 306A, weighting unit 308A, and phase shifter 5201 of Figure 62 relevant to frequency band Y to generate modulated signal 5202. Then, a transmission signal corresponding to the modulated signal 52 02 is transmitted by the antenna 1310A of Fig. 13, that is, by the antenna 6210B of Fig. 62.
<img file="MX385274B_D0199.tif" />
194
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
As shown in Figure 66 (Figure 66 illustrates the frame configuration of the modulated signal transmitted by the base station, with time on the horizontal axis and frequency on the vertical axis), the base station transmits the transmission scheme information 6601, phase shift information applied to repeater 6602, and data symbols 6603. The repeater obtains and applies the transmission pattern information 6601, the phase shift information applied to the repeater 6602, and the data symbols 6603 to the transmission signal, thereby determining the phase shift pattern. When the phase shift information applied to repeater 6602 in Fig. 66 is not included in the signal transmitted by the base station, then as shown in Fig. 62, repeater Β (6203B) is the master and indicates the phase shift scheme to repeater A (6203A).
As already explained, when the repeater transmits different data, the precoding matrix and phase shift scheme are set according to the transmission scheme to generate the modulated signals.
On the other hand, to transmit identical data, two repeaters respectively generate the transmit modulated signals. In such circumstances, the repeaters each generating the modulated signals for transmission from a common antenna can be considered as two combined repeaters using the precoding matrix given by Mathematics 52
<img file="MX385274B_D0200.tif" />
195
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY (Formula 52) . The phase change scheme is as explained in the Cl modality, for example, and meets the conditions of Math 53 (formula 53).
Furthermore, as explained in modality Cl for the frequency band X, the base station and the repeater can each have two antennas that transmit the respective modulated signals and two antennas that receive the identical data. The operations of such a base or repeater station are as described for the Cl mode.
According to the present embodiment, not only can the receiving device obtain improved data reception quality for the transmission of identical data as well as the transmission of different data, but the transmitting devices can also share a data changer. phase.
Also, although the present embodiment explains examples using OFDM as the transmission scheme, the invention is not limited in that sense. Multi-carrier schemes other than OFDM and single-carrier schemes can be used to achieve similar modalities. Here, spread spectrum communications can also be used. When single carrier schemes are used, the phase change is done with respect to the time domain.
As explained in mode 3, when the transmission scheme involves the transmission of different data, the
<img file="MX385274B_D0201.tif" />
196
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY phase change is performed only on the data symbols. However, as described in the present embodiment, when the transmission scheme involves transmission of identical data, the phase change need not be limited to the data symbols but may also be performed on the pilots, control symbols and other such symbols inserted in the transmission frame of the transmission signal. (Phase shifting need not always be performed on symbols such as pilot symbols and control symbols, although doing so is preferred in order to achieve diversity gain).
C4 modality
The present embodiment refers to a phase change scheme different from the phase change schemes described in embodiment 1 and the supplement.
In Mode 1, Math 36 (formula 36) is given as an example of a precoding matrix, and in the supplement, Math 50 (formula 50) is similarly given as another such example. In Mode Al, the phase shifters of Figures 3, 4, 6, 12, 25, 29, 51 and 53 are indicated as having a phase shift value of PHASE[i] (where i = 0, 1, two ... N-2, Nl, that is, O^i^Nl, i being an integer) to achieve a period (cycle) of N (value reached, given that figures 3, 4, 6, 12, 25, 29, 51 and 53 perform the phase shift on a baseband signal only). The present description explains performing a phase shift on a pre-encoded baseband signal (i.e., in
<img file="MX385274B_D0202.tif" />
197
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY Figures 3, 4, 6, 12, 25, 29 and 51) that is, in the precoded baseband signal z2'. Here, PHASE [k] is calculated as follows.
[Mathematics 54] (formula 54)
PHASE [k]= —
N radians where k=0<sub>F</sub> 1, 2... N-2, Nl, ie O^k^N-1, k being an integer.
Accordingly, the receiving device can achieve improvements in data reception quality in the LOS environment, and especially in a radio wave propagation environment. In the LOS environment, when the phase change has not been performed, a regular phase relationship is maintained. However, when the phase shift is performed, the phase relationship is changed, in turn avoiding poor conditions in a burst propagation environment. As an alternative to Math 54 (formula 54), PHASE[k] can be calculated as follows.
[Mathematics 55] (formula 55)
PHASE[k] = radians N where k = 0, 1, 2... N-2, Nl, ie O^k^N-1, Taking an integer.
As a further alternative phase change scheme, PHASE[k] can be calculated as follows.
<img file="MX385274B_D0203.tif" />
198
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
[Mathematics 56] (formula 56)
PHASE [k]=—+Z radians N where k = 0, 1, 2... N-2, Nl, ie O^k^N-1, k being an integer and Z being a fixed value.
As a further alternative phase change scheme, PHASE[k] can be calculated as follows.
[Mathematics 57] (formula 57)
PHASE [k} = - — +Z radians where k=0, 1, 2... N-2, Nl, ie O^k^N-1, Assuming an integer and Z is a fixed value.
Thus, by performing the phase change according to the present embodiment, the receiving device is more likely to be made so as to obtain good reception quality.
The phase shift of the present embodiment is applicable not only to single-carrier schemes but also to multi-carrier schemes. Accordingly, the present embodiment can also be achieved using, for example, spread spectrum communications, OFDM, SC-FDMA, SC-OFDM, miniwave OFDM, as described in Non-Patent Literature 7, etc. As already described, although the present modality explains
<img file="MX385274B_D0204.tif" />
199
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY the phase change by changing the phase with respect to the time domain t, the phase can alternatively change with respect to the frequency domain, as described in Modality 1. That is, considering the change of phase in the time domain t described in the present embodiment and replacing t by f (where f is the ((sub-)carrier) frequency) leads to a phase shift applicable to the frequency domain. Furthermore, as already explained for embodiment 1, the phase shift scheme of the present embodiment is also applicable to a phase shift in both the time domain and the frequency domain. Also, when the phase change scheme described in the present embodiment satisfies the conditions indicated in the Al mode, the receiving device is very likely to obtain good data quality.
C5 mode
The present embodiment relates to a phase change scheme different from the phase change schemes described in Mode 1, in the supplement and in Mode C4.
In Mode 1, Math 36 (formula 36) is given as an example of a precoding matrix and in the supplement, Math 50 (formula 50) is similarly given as another such example. In Mode Al, the phase shifters of Figures 3, 4, 6, 12, 25, 29, 51 and 53 are indicated as having a phase shift value of PHASE[i] (where i = 0, 1 , two ... N-2, Nl, that is, O^i^Nl, i being an integer) to achieve a period (cycle) of N (value reached given that figures 3, 4, 6, 12,
<img file="MX385274B_D0205.tif" />
200
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
25, 29, 51 and 53 perform the phase shift on a baseband signal only). The present description explains performing a phase shift on a pre-encoded baseband signal (ie in Figures 3, 4, 6, 12, 25, 29, 51 and 53) i.e. on the pre-encoded baseband signal z2' .
The characteristic feature of the phase change scheme relevant to the present embodiment is the period (cycle) of N = 2n + 1. To achieve the period (cycle) of N = 2n + 1, n+1 different change values are prepared of phase. Among those n+1 different phase shift values, n phase shift values are used twice per period (cycle) and one phase shift value is used only once per period (cycle), thus achieving way the period (cycle) of N = 2n + 1. The following describes these phase shift values in detail.
The n+1 different phase shift values required to achieve a phase shift scheme in which the phase shift value changes regularly over a period (cycle) of N = 2n +1 are expressed as PHASE [0] , PHASE [1], PHASE [i] ... PHASE [n-1] , PHASE [n] (where i = 0, 1, 2... n-2, n-1, n, i.e. Oíi^ N-1, i being an integer) . Here, the n+1 different phase shift values of PHASE[0], PHASE[1], PHASE[i] ... PHASE[n-1], PHASE[n] are expressed as follows.
[Mathematics 58] (formula 58) le 7T
PHASE [£] = radians 2n +1
<img file="MX385274B_D0206.tif" />
201
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY where k = 0, 1, 2... n-2, nl, n, that is, O^k^N-1, k being an integer. The n+1 different phase shift values PHASE[0], PHASE[1]...PHASE[i]...PHASE[nl], PHASE[n] are given by Math 58 (formula 58). PHASE[0] is used once, while PHASE[1] through PHASE[n] are each used twice (i.e., PHASE[1] is used twice, PHASE[2] is used twice , etc., until PHASE[nl] is used twice and PHASE[n] is used twice) . By itself, through this phase change scheme in which the phase change value regularly changes in a period (cycle) of N = 2n +1, a phase change scheme in which it regularly changes is realized the phase shift value among fewer phase shift values. In this way, the receiving device can achieve better data receiving quality. Since the phase shift values are less, the effect thereof on the transmitting device and receiving device can be reduced. According to the above, the receiving device can achieve improvements in data reception quality in the LOS environment, and especially in a radio wave propagation environment. In the LOS environment, when the phase change has not been performed, a regular phase relationship occurs. However, when the phase shift is performed, the phase relationship is changed, in turn avoiding poor conditions in a burst propagation environment. As an alternative to Math 54 (formula 54), PHASE[k] can be computed
<img file="MX385274B_D0207.tif" />
202
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY as follows.
[Mathematics 59] (formula 59) will go
PHASE [A] = radians 2/7 + 1 where k = 0, 1, 2... n-2, n-1, n, i.e. O^k^N-1, k being an integer.
The n+1 different phase shift values PHASE [0], PHASE [1] ... PHASE [i] ... PHASE[n-1], PHASE[n] are given by Math 59 (formula 59) . PHASE[0] is used once, while PHASE[1] through PHASE[n] are each used twice (i.e., PHASE[1] is used twice, PHASE[2] is used twice). times, etc., until PHASE[n-1] is used twice and PHASE[n] is used twice) . Thus, through this phase change scheme in which the phase change value regularly changes in a period (cycle) of N = 2n +1, a phase change scheme in which the regularly changes the phase shift value among fewer phase shift values. In this way, the receiving device can achieve better data receiving quality. Since the phase shift values are less, the effect thereof on the transmitting device and receiving device can be reduced.
As a further alternative, PHASE[k] can be calculated as follows.
<img file="MX385274B_D0208.tif" />
203
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
[Mathematics 60] (formula 60)
PHASE [k]=— + Z radians 2n +1 where k = 0, 1, 2... n-2, n-1, n, that is, 0¿k<Nl, k being an integer and Z being an fixed value.
The n+1 different phase shift values PHASE [0], PHASE [1] ... PHASE [i] ... PHASE [n-1], PHASE[n] are given by Math 60 (formula 60) . PHASE[0] is used once, while PHASE[1] through PHASE[n] are each used twice (i.e., PHASE[1] is used twice, PHASE[2] is used twice). times, etc., until PHASE[n-1 is used twice and PHASE [n] is used twice) . Thus, through this phase change scheme in which the phase change value regularly changes in a period (cycle) of N = 2n +1, a phase change scheme in which the regularly changes the phase shift value among fewer phase shift values. In this way, the receiving device can achieve better data reception quality. Since the phase shift values are less, the effect thereof on the transmitting device and receiving device can be reduced.
As a further alternative, PHASE[k] can be calculated as follows.
<img file="MX385274B_D0209.tif" />
204
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
[Math 61] (formula 61) PHASE [k] = + Z radians + 1 where k = 0, 1, 2... n-2, n-1, n, i.e. O^k^N-1, k being an integer and Z being a fixed value.
The n+1 different phase shift values PHASE [0] , PHASE [1] ... PHASE [i] ... PHASE [n-1] , PHASE [n] are given by Math 61 (formula 61) . PHASE [0] is used once, while PHASE [1] through PHASE [n] are each used twice (i.e., PHASE [1] is used twice, PHASE[2] is used twice). times, etc., until PHASE[n-1] is used twice and PHASE [n] is used twice) . Thus, through this phase change scheme in which the phase change value regularly changes in a period (cycle) of N = 2n +1, a phase change scheme in which the regularly changes the phase shift value among fewer phase shift values. In this way, the receiving device can achieve better data reception quality. Since the phase shift values are smaller, the effect thereof on the transmitting device and the receiving device can be reduced.
By itself, by performing the phase change according to the present embodiment, the receiving device is more likely to obtain good reception quality.
The phase change of the present embodiment is
<img file="MX385274B_D0210.tif" />
205
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY applicable not only to single carrier schemes but also to transmission using multicarrier schemes. Accordingly, the present embodiment can also be achieved using, for example, spread spectrum communications, OFDM, SC-FDMA, SC-OFDM, miniwave OFDM, as described in Non-Patent Literature 7, etc. as already described, although the present embodiment explains the phase change as a phase change with respect to the time domain t, the phase may alternatively change with respect to the frequency domain, as described in Mode 1. It is That is, considering the phase shift with respect to the time domain t described in the present embodiment and replacing t with f (where f is the ((sub-)carrier) frequency) leads to a phase shift applicable to the frequency domain. Furthermore, as already explained for embodiment 1, the phase shift scheme of the present embodiment is also applicable to a phase shift with respect to both the time domain and the frequency domain.
C6 mode
The present embodiment describes a scheme for regularly changing the phase, specifically that of the C5 mode, when encoding is performed using block codes as described in Non-patent Literature 12 to 15, such as QC LDPC codes (can be used without only QC-LDPC but also LDPC codes), LDPC concatenated codes (blocks) and BCH codes, turbo codes or duo-binary turbo codes using tail bits,
<img file="MX385274B_D0211.tif" />
206
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY etc. The following example considers a case where two currents si and s2 are transmitted. When the encoding has been performed using the block codes and control information and the like are not necessary, the number of bits constituting each encoded block coincides with the number of bits constituting each block code (information of control etc. described below). When encoding has been performed using block codes or the like and control information or the like is not required (for example, CRC transmission parameters), the number of bits constituting each encoded block is the sum of the number of bits that constitute the block codes and the number of bits that constitute the information.
Figure 34 illustrates the varying amounts of symbols and intervals required in two coded blocks when block codes are used. Figure 34 illustrates the varying numbers of symbols and intervals required in each coded block when block codes are used if, for example, two streams si and s2 are transmitted as indicated by the transmission device of Figure 4, and the device transmission has only one encoder. (Here, the transmission scheme may be any single carrier scheme or multi-carrier scheme such as OFDM).
As shown in figure 34, when block codes are used, there are 6000 bits that constitute a single block
<img file="MX385274B_D0212.tif" />
207
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY codified. finally. To transmit those 6,000 bits, the number of symbols required depends on the modulation scheme, being 3,000 symbols for QPSK, 1,500 symbols for 16-QAM, and 1,000 symbols for QPSK.
64-QAM.
Then, since the transmission device of Fig. 4 transmits two streams simultaneously, 1500 of the aforementioned 3000 symbols needed when the modulation scheme is QPSK are assigned to si and the other 1500 symbols are assigned to s2. Thus, 1500 slots are required to transmit the 1500 symbols to each of si and S2 .
By the same reasoning, when the modulation scheme is 16-QAM, it takes 750 slots to transmit all the bits that make up a coded block, and when the modulation scheme is 64-QAM, it takes 500 slots to transmit all the bits. that constitute a coded block.
The following describes the relationship between the above defined intervals and phase, as relevant to schemes for a regular phase change.
Here, five different phase change values (or phase change sets) are assumed to be ready for use in the scheme for a regular phase change, which has a period (cycle) of five. That is, the phase shifter of the transmission device of Figure 4 uses five phase shift values (or phase shift sets) to achieve the
<img file="MX385274B_D0213.tif" />
208
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY period (cycle) of five. However, as described in the C5 mode, there are three different phase shift values. Consequently, some of the five phase change values required for the period (cycle) of five are identical. (As in Figure 6, five phase shift values are needed to perform a phase shift with a period (cycle) of five on the pre-encoded baseband signal z2' only. Furthermore, as in Fig. 26, two phase shift values are needed in each interval to perform the phase shift on both the pre-encoded baseband signals zl' and z2'. Those two phase shift values are called a phase shift set. Therefore, five phase change sets should ideally be prepared to perform a phase change with a period (cycle) of five under such circumstances). The five phase shift values (or phase shift sets) needed for the period (cycle) of five are expressed as P[0], P[1], P[2], P[3], and P[ 4] .
The following describes the relationship between the above defined intervals and phase, as relevant to schemes for a regular phase change.
For the previously described 1500 slots necessary to transmit the 6000 bits that make up a single coded block when the modulation scheme is QPSK, the phase shift value P[0] is used in the 300 slots, the phase shift value is used phase P[l] in the 3 00 intervals, the value of phase shift P[2] is used in the 300 intervals, the value of
<img file="MX385274B_D0214.tif" />
209
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY phase change P[3] in the 300 intervals and the phase change value P[4] is used in the 300 intervals. This is due to the fact that any deviation in the use of the phase shift value causes great influence which should be exerted by the most frequently used phase shift value, since the receiving device depends on such an influence for the reception quality of the signal. the data.
Similarly, for the previously described 750 slots needed to transmit the 6000 bits that make up a single coded block when the modulation scheme is 16-QAM, the phase shift value P[0] is used in the 150 slots, use phase shift value P[l] in all 150 slots, use phase shift value P[2] in all 150 slots, the phase shift value P[3] is used in the 150 slots and the phase shift value P[4] is used in the 150 slots.
Likewise, for the previously described 500 intervals necessary to transmit the 6000 bits that constitute a single coded block when the modulation scheme is 64-QAM, the phase shift value P[□] is used in the 100 intervals, the phase shift value P[1] in the 100 slots, phase shift value P[2] is used in the 100 slots, phase shift value P[3] is used in the 100 slots, and the phase change value P[4] in the 100 intervals.
<img file="MX385274B_D0215.tif" />
210
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
As already described, a phase shift scheme for a regular phase shift value as given in Mode C5 requires the preparation of N = 2n + 1 phase shift values P[0], P[l ] ...P[2n-1], P [2n] (where P[0] , P[l] ...P[2n-1], P[2n] are expressed as PHASE [0] , PHASE[ 1], PHASE[2] ... PHASE[nl], PHASE[n] (see Mode C5)). Thus, in order to transmit all the bits that make up a single coded block, the phase shift value P[0] is used in the K<sub>either</sub> intervals, the phase shift value P[l] is used in the K intervals, the phase shift value P[i] is used in the Ki intervals (where i = 0, 1, 2...2n-l, 2n ) and the phase shift value P[2n] is used in the K<sub>2n</sub> intervals, so that Condition #C01 is met.
(Condition #C01)
Ko = Ki ...= Ki = ... K<sub>2n</sub>. That is, Ka = Kb (Va and Vb where a, b, =0, 1, 2 ... 2n-l, 2n (where a, b are integers between 0 and 2n, a # b) .
A phase shift scheme for a regular phase shift value as given in Mode C5 with a period (cycle) of N = 2n +1 requires the preparation of the phase shift values PHASE[0], PHASE [1], PHASE [2] ... PHASE [n-1] , PHASE[n]. Thus, in order to transmit all the bits that make up a single coded block, the phase shift value PHASE[0] is used in G<sub>either</sub> intervals, the phase shift value PHASE [1] is used in Gi intervals, the phase shift value
<img file="MX385274B_D0216.tif" />
211
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
PHASEfi] is used on Gi intervals (where i = 0, 1, 2...nl, n, i.e. O^í^Nl, i being an integer) , and the phase shift value
PHASE [n] is used in G<sub>n</sub> intervals, so that the
Condition #C01. Condition #C01 can be modified as follows.
(Condition #C02)
2xG<sub>0</sub> = Gi ...= Gi = ... G<sub>n</sub>. i.e. 2xG<sub>0</sub> =G<sub>a</sub> (Goes where a = 1, 2 ... n-1, n (where a is an integer between 1 and n) .
Then, when a communication system that supports multiple modulation schemes selects one such supported scheme to use, Condition #C01 (or Condition #C02) for the supported modulation scheme should preferably be met.
However, when multiple modulation schemes are supported, each such modulation scheme typically uses symbols that transmit a different number of bits per symbol (although it may happen that some use the same number), Condition #C01 (or Condition #C01) may not be met. Condition #C02) in some modulation schemes. In such a case, the following condition applies instead of Condition #C01.
(Condition #C03)
The difference between K<sub>a</sub> and Kb satisfies 0 or 1. That is, | Ka - Kb| satisfies 0 or 1 (Va, Vb, where a, b = 0, 1, 2 ... 2n-l, 2n (a and b being integers between 0 and 2n) a / b).
Alternatively, Condition #C03 can be expressed as
<img file="MX385274B_D0217.tif" />
212
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY as follows.
(Condition #C04)
The difference between G<sub>a</sub> and Gb satisfies 0, 1 or 2. That is, |G<sub>a</sub> -Gb| satisfies 0, 1 or 2 (Va, Vb, where a, b = 1, 2 ... nl, n (a and b being integers between 1 and n) ab)
Y
The difference between 2xG<sub>0</sub> and G<sub>a</sub> satisfies 0, 1 or 2 . That is, |2xG<sub>0</sub> -G<sub>a</sub>| satisfies 0, 1 or 2 (Va, where a = 1, 2 ... nl, n (where a is an integer between 1 and n)).
Figure 35 illustrates the varying amounts of symbols and intervals required in two coded blocks when block codes are used. Figure 35 illustrates the varying numbers of symbols and intervals required in each coded block when block codes are used if, for example, two streams si and s2 are transmitted as indicated by the transmission device of Figure 3 and Figure 12 , and the transmitting device has two encoders. (Here, the transmission scheme may be any single carrier scheme or multi-carrier scheme such as OFDM).
As shown in Figure 35, when block codes are used, there are 6000 bits that make up a single coded block. In order to transmit those 6,000 bits, the number of symbols required depends on the modulation scheme, being 3,000 for QPSK, 1,500 for 16-QAM, and 1,000 for 64-QAM.
The transmission device of figure 3 and the
<img file="MX385274B_D0218.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
213 transmission device in Figure 12 each transmit two streams at a time, and have two encoders. By themselves, the two streams each transmit different code blocks. Therefore, when the modulation scheme is QPSK, two coded blocks extracted from si and s2 are transmitted within the same slot, eg, a first coded block extracted from si is transmitted, then a second coded block extracted from s2 is transmitted. Thus, 3000 slots are needed to transmit the first and second coded blocks.
By the same reasoning, when the modulation scheme is 16-QAM, it takes 1500 slots to transmit all the bits that make up a coded block, and when the modulation scheme is 64-QAM, it takes 1000 slots to transmit all the bits. that constitute a coded block.
The following describes the relationship between the above defined intervals and phase, as relevant to schemes for a regular phase change.
Here, five different phase change values (or phase change sets) are assumed to be ready for use in the scheme for a regular phase change, which has a period (cycle) of five. That is, the phase shifter of the transmission device of Figure 4 uses five phase shift values (or phase shift sets) to achieve the period (cycle) of five. However, as described in
<img file="MX385274B_D0219.tif" />
214
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY modality C5, there are three different phase change values. Consequently, some of the five phase change values required for the period (cycle) of five are identical. (As in Figure 6, five phase shift values are needed to perform the phase shift with a period (cycle) of five on the pre-encoded baseband signal z2' only. Furthermore, as in Fig. 26, two phase shift values are needed for each interval in order to perform the phase shift on both the pre-encoded baseband signals zl' and z2'. Those two phase shift values are called a phase shift set. Therefore, ideally five phase change sets should be prepared to perform a phase change with a period (cycle) of five under such circumstances). The five phase shift values (or phase shift sets) needed for the period (cycle) of five are expressed as P[0], P[l], P[2], P[3] , and P[ 4] .
For the previously described 3000 slots necessary to transmit the 6000x2 bits that make up the coded block pair when the modulation scheme is QPSK, the phase shift value P[0] is used in the 600 slots, the phase shift value P[l] is used in all 600 slots, phase shift value P[2] is used in all 600 slots, phase shift value P[3] is used in 6100 slots, and phase shift value P[4] is used in the 600 intervals. This is due to the fact that any deviation in the use of the exchange value of
<img file="MX385274B_D0220.tif" />
215
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY phase causes great influence that should be exercised by the most frequently used phase shift value, since the receiving device depends on such influence for the quality of data reception.
Also, in order to transmit the first coded block, the phase shift value P[0] is used in the intervals of 600 times, the phase shift value P[l] is used in the intervals of 600 times, the phase shift value P[2] is used in the intervals of 600 times, phase shift value P[3] is used in the intervals of 600 times, and phase shift value PHASE[4] is used at intervals of 600 times. Also, in order to transmit the second coded block, the phase shift value P[0] is used in intervals of 600 times, the phase shift value P[1] is used in intervals of 600 times, the phase shift value P[2] is used in intervals of 600 times, phase shift value P[3] is used in intervals of 600 times, and phase shift value P[4] is used at intervals of 600 times.
Similarly, for the previously described 1500 slots needed to transmit the 6000x2 bits that make up the coded block pair when the modulation scheme is 16-QAM, the phase shift value P[0] is used in the 300 intervals, the phase shift value P[1] is used in the 300 intervals, the phase shift value P[2] is used in the 300 intervals, the phase shift value P[3] is used in the 300
<img file="MX385274B_D0221.tif" />
216
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY intervals, and the phase change value P[4] is used in the 300 intervals.
Also, in order to transmit the first coded block, the phase shift value P[0] is used in intervals of 300 times, the phase shift value P[l] is used in intervals of 300 times, the phase shift value P[2] is used in the intervals of 300 times, phase shift value P[3] is used in the intervals of 300 times, and phase shift value P[4] is used at intervals of 300 times. Also, in order to transmit the second coded block, the phase shift value P[0] is used in intervals of 300 times, the phase shift value P[1] is used in intervals of 300 times , the phase shift value P[2] is used in the intervals of 300 times, the phase shift value P[3] is used in the intervals of 300 times, and the phase shift value P[4] is used at intervals of 300 times.
Likewise, for the previously described 1000 slots necessary to transmit the 6000x2 bits that constitute the two coded blocks when the modulation scheme is 64-QAM, the phase shift value P[0] is used in the 200 slots, the value of phase shift P[1] is used in all 200 slots, phase shift value P[2] is used in all 200 slots, phase shift value P[3] is used in all 200 slots, and the phase shift value P[4] is used in the 200 intervals.
<img file="MX385274B_D0222.tif" />
217
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Also, in order to transmit the first coded block, the phase shift value P[0] is used in the intervals of 200 times, the phase shift value P[l] is used in the intervals of 200 times, the phase shift value P[2] is used in intervals of 200 times, phase shift value P[3] is used in intervals of 200 times, and phase shift value P[4] is used at intervals of 200 times. Also, in order to transmit the second coded block, the phase shift value P[0] is used in intervals of 200 times, the phase shift value P[l] is used in intervals of 200 times, the phase shift value P[2] is used in the intervals of 200 times, phase shift value P[3] is used in the intervals of 200 times, and phase shift value P[4] is used at intervals of 200 times.
As already described, a phase change scheme to regularly vary the phase change value as given in the C5 mode requires the preparation of N = 2n + 1 phase change values P[0], P[l] ...P[2n-1], P [2n] (where P[0], P[l] ...P[2n-1], P[2n] are expressed as PHASE [0] , PHASE [1 ], PHASE [2] ... PHASE[nl], PHASE[n] (see mode C5)). Thus, in order to transmit all the bits that make up the two coded blocks, the phase shift value P[0] is used in the Ko intervals, the phase shift value P[l] is used in the Ki intervals, the phase shift value P[i] is used in the Ki intervals (where i = 0, 1, 2...2n-l, 2n, i.e. 0^i^2n, i being
<img file="MX385274B_D0223.tif" />
218
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY an integer), and the phase change value P[2n] is used in the K<sub>2n</sub>intervals, so that Condition #C01 is met.
(Condition #C05)
K<sub>either</sub> = Ki ..- Ki = ... K<sub>2n</sub>. That is, K* = K<sub>b</sub> (Va and Vb where a, b, = 0, 1, 2 ... 2n-l, 2n (where a, b are integers between 0 and 2n, a Ψ b) . In order to transmit all the bits that constitute the first coded block, the phase shift value P[0] is used K<sub>0</sub>,i times, the phase shift value P[1] is used Κι,ι times, the phase shift value P[i] is used Ki<sub>(1</sub> (where i = 0, 1, 2 ... 2n-l, 2n, i.e. 0^i^2n, i being an integer), and the phase shift value P[2n] is used K<sub>2n</sub>, i times.
(Condition #C06)
Κο,ι = Κχ,ι ...= Kj<sub>z</sub>i = ...K<sub>2n</sub>,i That is, Ka,i<sup>=</sup> Kb,i (Va and Vb where a, b, =0,1,2 ... 2n-l, 2n (where a, b are integers between 0 and 2n, a / b).
In order to transmit all the bits that make up the second coded block, the phase shift value P[0] is used K<sub>0</sub>.2 times, the phase shift value P[1] Ki is used<sub>/2</sub> Sometimes the phase shift value P[i] Ki is used,<sub>2</sub> (where i = 0, 1, 2 ... 2n-l, 2n, i.e. 0^i^2n, i being an integer), and the phase shift value P[2n] K is used<sub>2n</sub>,2 times.
(Condition #C07)
Kq,2 = Kl,2 —<sup>—</sup> Ki,2 = — K2n,2- ES dedr, K<sub>a</sub>,2 = &b,2 (And Md where a, b, = 0, 1, 2 ... 2n-l, 2n (where a, b are integers between 0 and 2n, a / b) .
<img file="MX385274B_D0224.tif" />
219
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
A phase change scheme to regularly vary the phase change value as given in the C5 mode with a period (cycle) of N = 2n +1 requires the preparation of phase change values PHASE[0], PHASE[ 1], PHASE [2] ... PHASE [nl], PHASE[n]. Thus, in order to transmit all the bits that make up the two coded blocks, the phase shift value PHASE[0] is used in G<sub>either</sub> intervals, the phase shift value PHASE [1] is used in Gx intervals, the phase shift value PHASE [i] is used in Gi intervals (where i = 0, 1, 2...nl, n, is say, O^i^n, i being an integer), and the phase shift value PHASE[n] is used in G<sub>n</sub> intervals, so that Condition #C05 is met.
(Condition #C08)
2xG<sub>0</sub> = Gx ...= Gi = ... G<sub>n</sub>. i.e. 2xG<sub>0</sub> =G<sub>a</sub> (Goes where a = 1, 2 ... nl, n (where a is an integer between 1 and n) .
In order to transmit all the bits that make up the first coded block, the phase shift value PHASE[0] is used G<sub>0</sub>,i times, the phase shift value PHASE [1] is used Gi,i times, the phase shift value PHASE [i] is used Gj,i (where i = 0, 1, 2 ... nl, n, i.e. O^i^n) , and the phase shift value PHASE [n] is used G<sub>n>1</sub> times.
(Condition #C09)
2xG<sub>0/</sub>i = G<sub>1(1</sub> —= Gi<sub>z</sub>i = ...G<sub>n</sub>,Yo. That is, 2xGq<sub>(</sub>j = G<sub>a;</sub>i (Go where a = 1, 2 ... nl, n (where a is an integer between 1 and n) .
In order to transmit all the bits that constitute
<img file="MX385274B_D0225.tif" />
220
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY the second coded block, the phase shift value PHASE[0] is used G<sub>either</sub>.2 times, the phase shift value PHASE [1] is used G<sub>1>2 </sub>times, the phase shift value PHASE[i] is used G<sub>i/2</sub> (where i - 0, 1, 2 ... n-1, n, i.e. O^i^n) , and the phase shift value PHASE [n] is used G<sub>B/1</sub> times.
(Condition #C10)
2xG<sub>0/2</sub> = Gi<sub><2</sub> ...= Gi<sub>r2</sub> = ...G<sub>n</sub>,<sub>2</sub>. That is, 2xGq,<sub>2</sub> =G<sub>a</sub>,<sub>2 </sub>where a = 1, 2 ... n-1, n (where a is an integer between 1 and n) .
Then, when a communication system that supports multiple modulation schemes selects one such supported scheme to use, Condition #C05, Condition #C06, and Condition #C07 (or Condition #C08, Condition #C09, and Condition #C09) should preferably be met. Condition #C10) for the supported modulation scheme.
However, when multiple modulation schemes are supported, each such modulation scheme typically uses symbols that transmit a different number of bits per symbol (although it may happen that some use the same number), Condition #C05, Condition #C06 and Condition #C07 (or Condition #C08, Condition #C09 and Condition #C10) in some modulation schemes. In such a case, the following conditions apply in lieu of Condition #C05, Condition #C06 and Condition #C07.
(Condition #C11)
The difference between K<sub>a</sub> and K<sub>b</sub> satisfies 0 or 1. That is,
<img file="MX385274B_D0226.tif" />
221
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY |K<sub>a</sub> -K<sub>b</sub>| satisfies 0 or 1 (Va, Vb, where a, b = 0, 1, 2 ... 2n-l, 2n (a and b being integers between 0 and 2n) ab) .
(Condition #C12)
The difference between Ka,i and K<sub>b</sub>,i satisfies 0 or 1. That is, |K<sub>a</sub>,i - K<sub>b/</sub>i| satisfies 0 or 1 (Va, Vb, where a, b = 0, 1, 2 ... 2n-l,
2n (a and b being integers between 0 and 2n) ab).
(Condition #C13)
The difference between K<sub>a</sub>,<sub>2</sub> and K<sub>b)2</sub> satisfies 0 or 1. That is, | K<sub>a</sub>,<sub>2</sub> - Kb,21 satisfies 0 or 1 (Va, Vb, where a, b = 0, 1, 2 ... 2n-l, 2n (a and b being integers between 0 and 2n) a Ψ b).
Alternatively, Condition #C11, Condition #C12 and Condition #C13 may be expressed as follows.
(Condition #C14)
The difference between G<sub>a</sub> and G<sub>b</sub> satisfies 0, 1 or 2 . That is, |G<sub>a</sub> -G<sub>b</sub>| satisfies 0, 1 or 2 (Va, Vb, where a, b = 1, 2 ... nl, n (a and b being integers between 1 and n) a # b) and
The difference between 2xG<sub>0</sub> and G<sub>a</sub> satisfies 0, 1 or 2 . That is, |2xG<sub>0</sub> -G<sub>a</sub>| satisfies 0, 1 or 2 (Va, where a = 1, 2 ... nl, n (where a is an integer between 1 and n)).
(Condition #C15)
The difference between G<sub>a</sub>,i and G<sub>b/1</sub> satisfies 0, 10 2. That is, |G<sub>a</sub>,i - Gh,i| satisfies 0, 1 or 2 (Va, Vb, where a, b = 1, 2 ... nl, n (a and b being integers between 1 and n) a / b) and
<img file="MX385274B_D0227.tif" />
222
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
The difference between 2xG<sub>0</sub>,i and G<sub>a</sub>,i satisfies 0, 1 6 2. That is, |2xG<sub>0</sub>,i - G<sub>a</sub>,i| satisfies 0, 1 or 2 (Go, where a = 1, 2 ... n-1, n (where a is an integer between 1 and n)) (Condition #C16)
The difference between G<sub>a</sub>,2 and Gt, 2 satisfies 0, 1Ó2. That is, |G<sub>a</sub>,<sub>2</sub> -gb<sub>/2</sub>| satisfies 0, 1 or 2 (Va, Vb, where a, b = 1, 2 ... n-1, n (a and b being integers between 1 and n) a / b) and
The difference between 2xG<sub>0</sub>,<sub>2</sub> and G<sub>a</sub>,<sub>2</sub> satisfies 0, 1 or 2. That is, |2xG<sub>0/2</sub> -G<sub>a</sub>,2| satisfies 0, 1 or 2 (Va, where a = 1, 2 ... n-1, n (where a is an integer between 1 and n) ) .
As already described, the offset between the phase shift values used to transmit the coded blocks is eliminated by creating a relationship between the coded block and the phase shift values. In this way, you can improve the reception quality of the data for the receiving device.
In the present embodiment, N phase change values (or phase change sets) are needed for the phase change mode with a period (cycle) of N with a regular phase change scheme. By itself, N phase shift values (or phase shift sets) are prepared P[0] , P[l] , P[2] ... P[N-2] , and P[N-1 ]. However, there are schemes to order the phases in the established order with respect to the frequency domain. In this sense, no limitation is foreseen. The N values
<img file="MX385274B_D0228.tif" />
223
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY of phase change (or phase change sets) P[0] , P[1] , P[2] ... P[N-2], and P[N-1] as well they can change the phases of blocks in the time domain or in the time-frequency domain to obtain a symbol arrangement as described in mode 1. Although the preceding examples explain a phase shift scheme with a period (cycle) of N, the same effects can be obtained by using N phase shift values (or phase shift sets) randomly. That is, the N phase change values (or phase change sets) need not always have regular periodicity. As long as the conditions described above are met, improvements in data reception quality can be achieved for the receiving device.
Also, given the existence of modes for spatial multiplexing MIMO schemes, MIMO schemes using a fixed precoding matrix, space-time block coding schemes, single stream transmission, and schemes using a phase shift On a regular basis, the transmitting device (broadcasting station, base station) can select any of those transmission schemes.
As described in Non-Patent Literature 3, spatial multiplexing MIMO schemes involve transmitting the signals si and s2, which are correlated using a selected modulation scheme, on each of two different antennas.
<img file="MX385274B_D0229.tif" />
224
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
MIMO schemes using a fixed precoding matrix involve performing precoding only (without any phase shift). In addition, space-time block coding schemes are described in Non-Patent Literature 9, 16, and 17. Single-stream transmission schemes involve transmitting the signal si, correlated to a selected modulation scheme, from an antenna after performing default processing.
Schemes using multi-carrier transmission such as OFDM involve a first carrier group consisting of multiple carriers and a second carrier group consisting of multiple carriers different from the first carrier group, etc., such that multi-carrier transmission is performed with multiple carrier groups. For each carrier group, any of the spatial multiplexing MIMO schemes, MIMO schemes using a fixed precoding matrix, space-time block coding schemes, single stream transmission, and schemes using a regular phase change. In particular, schemes using a regular phase shift in a selected group of (sub-)carriers are preferably used to perform the present embodiment.
When a phase shift is performed, for example, by a phase shift value for P[i] of X radians on just a pre-encoded baseband signal, the shifters
<img file="MX385274B_D0230.tif" />
225
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY phase of figures 3, 4, 6, 12, 25, 29, 51 and 53 multiply the pre-encoded baseband signal z2 ' by e<sup>jX</sup>. Then, when a phase shift is performed, for example, by a phase shift set for P[i] of X radians and Y radians on both pre-encoded baseband signals, the phase shifters of Figures 26, 27, 28, 52 and 54 multiply the pre-encoded baseband signal z2' by e<sup>]X</sup> and multiply the pre-encoded baseband signal zl' by e-*<sup>Y</sup>.
C7 mode
The present embodiment describes a scheme for regularly changing the phase, specifically communication or performed in Al mode and C6 mode, when encoding is performed using the block codes as described in Non-Patent Literature 12 to 15, such as QC LDPC codes (not only QC-LDPC codes but also LDPC (block) codes can be used), concatenated LDPC and BCH codes, turbo codes or duo-binary turbo codes, etc. The following example considers a case where two currents si and s2 are transmitted. When the encoding has been performed using block codes and control information and the like are not necessary, the number of bits constituting each encoded block coincides with the number of bits constituting each block code (control information may also be included etc. described below). When the coding has been done using block codes or the like and control information is required
<img file="MX385274B_D0231.tif" />
226
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY or similar (for example, CRC transmission parameters), the number of bits that make up each coded block is the sum of the number of bits that make up the block codes and the number of bits that make up the information .
Figure 34 illustrates the varying amounts of symbols and intervals required in an encoded block when block codes are used. Figure 34 illustrates the varying numbers of symbols and intervals required in each coded block when block codes are used if, for example, two streams si and s2 are transmitted as indicated by the transmission device of Figure 4, and the device transmission has only one encoder. (Here, the transmission scheme may be any single carrier scheme or multi-carrier scheme such as OFDM).
As shown in Figure 34, when block codes are used, there are 6000 bits that make up a single coded block. In order to transmit those 6,000 bits, the number of symbols required depends on the modulation scheme, being 3,000 symbols for QPSK, 1,500 symbols for 16-QAM, and 1,000 symbols for 64-QAM.
Then, since the transmitting device in Figure 4 transmits two streams simultaneously, 1500 of the previously mentioned ones that need 3000 when the modulation scheme is QPSK are assigned to si and the other 1500 symbols are assigned to s2 . Thus, 1500 intervals are required to
<img file="MX385274B_D0232.tif" />
227
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY transmit the 1500 symbols (hereinafter intervals) for each of si and s2.
By the same reasoning, when the modulation scheme is 16-QAM, it takes 750 slots to transmit all the bits that make up a coded block, and when the modulation scheme is 64-QAM, it takes 500 slots to transmit all the bits. that constitute a coded block.
The following describes the relationship between the above defined intervals and phase, as relevant to schemes for a regular phase change.
Here, five different phase change values (or phase change sets) are assumed to be ready for use in the scheme for a regular phase change, which has a period (cycle) of five. The phase change values (or phase change sets) prepared to regularly change phase with a period (cycle) of five are P[0], P[1], P[2], P[3], and P[ 4]. However, P[0], P[1] , P[2] , P[3] and P[4] must include at least two different phase shift values (that is, P[0] , P[1] , P[2] , P[3] , and P[4] can include identical values of phase shift). (As in Figure 6, five phase shift values are needed to perform a phase shift with a period (cycle) of five on the pre-encoded baseband signal z2' only. Furthermore, as in Fig. 26, two phase shift values are needed for each interval in order to perform the phase shift on both the pre-encoded baseband signals zl' and z2'. These
<img file="MX385274B_D0233.tif" />
228
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY two phase change values are called the phase change set. Therefore, ideally five phase change sets should be prepared to perform a phase change with a period (cycle) of five under such circumstances).
For the previously described 1500 slots necessary to transmit the 6000 bits that constitute a single coded block when the modulation scheme is QPSK, the phase shift value P[0] is used in the 300 slots, the phase shift value P[ l] is used in the 300 slots, the phase shift value P[2] is used in the 300 slots, the phase shift value P[3] is used in the 300 slots, and the phase shift value P[2] is used in the 300 slots, phase P[4] is used in the 300 slots. This is due to the fact that any deviation in the use of the phase shift value causes great influence which should be exerted by the most frequently used phase shift value, since the receiving device depends on such an influence for the reception quality of the signal. the data.
Likewise, for the previously described 750 slots needed to transmit the 6000 bits that make up a single coded block when the modulation scheme is 16-QAM, the phase shift value P[0] is used in the 150 slots, the phase shift value P[l] is used in all 150 slots, phase shift value P[2] is used in all 150 slots, phase shift value P[3] is used in all 150 slots, and the phase shift value P[4] is used in the 150
<img file="MX385274B_D0234.tif" />
229
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY intervals.
Furthermore, for the previously described 500 slots needed to transmit the 6000 bits that constitute a single coded block when the modulation scheme is 64-QAM, the phase shift value P[0] is used in the 100 slots, the value phase shift value P[l] is used in all 100 slots, phase shift value P[2] is used in all 100 slots, phase shift value P[3] is used in all 100 slots, and the phase shift value P[4] is used in the 100 slots.
As already described, the phase change values used in the phase change scheme that regularly switches between phase change values with a period (cycle) of N are expressed as P[0], P[1] ... P[N-2] , P[N-1 ] . However, P[0], P[1]... P[N-2] , P[N-1] must include at least two different phase shift values (that is, P[0], P[ l] — P[N-2], P [Nl] may include identical values of phase shift). In order to transmit all the bits that make up a single coded block, the phase shift value P[0] is used in the K<sub>either</sub> intervals, the phase shift value P[1] is used in the Ki intervals, the phase shift value P[i] is used in the Ki intervals (where i = 0, 1, 2...N-1 , that is, 0^í^Nl, i being an integer), and the phase shift value P[N-1] is used in the K<sub>N</sub>_i intervals, so Condition #C17 is met.
<img file="MX385274B_D0235.tif" />
230
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY (Condition #C17)
K<sub>either</sub> = Ki ...= Ki = ... K<sub>N</sub>_Yo. That is, K.<sub>a</sub> = Kb (Va and Vb where a, b, = 0, 1, 2 ... Nl (where a and b are integers between zero and Nl) a * b) .
Then, when a communication system that supports multiple modulation schemes selects such a supported scheme to use, Condition #C17 for the supported modulation scheme should preferably be met.
However, when multiple modulation schemes are supported, each such modulation scheme typically uses symbols that transmit a different number of bits per symbol (although it may happen that some use the same number). Condition #C17 may not be met in some schemes of modulation. In such a case, the following condition applies instead of Condition #C17.
(Condition #C18)
The difference between Ka and Kb satisfies 0 or 1. That is, |Ka - K<sub>b</sub>| satisfies 0 or 1 (Va, Vb, where a, b = 0, 1, 2 ... Nl (a and b being integers between 0 and 2n) a / b).
Figure 35 illustrates the varying amounts of symbols and intervals required in two coded blocks when block codes are used. Figure 35 illustrates the varying numbers of symbols and intervals required in each coded block when block codes are used if, for example, two streams si and s2 are transmitted as indicated by the device
<img file="MX385274B_D0236.tif" />
231
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY Figure 3 and Figure 12, and the transmission device has two encoders. (Here, the transmission scheme may be any single carrier scheme or multi-carrier scheme such as OFDM).
As shown in Figure 35, when block codes are used, there are 6000 bits that make up a single coded block. In order to transmit those 6,000 bits, the number of symbols required depends on the modulation scheme, being 3,000 symbols for QPSK, 1,500 symbols for 16-QAM, and 1,000 symbols for 64-QAM.
The transmission device of Figure 3 and the transmission device of Figure 12 each transmit two streams at a time, and have two encoders. Thus, the two streams each transmit different code blocks. Therefore, when the modulation scheme is QPSK, two coded blocks extracted from si and s2 are transmitted within the same interval, i.e., a first coded block extracted from si is transmitted, then a second coded block extracted from is transmitted. s2. By itself, 3000 slots are needed to transmit the first and second coded blocks.
By the same reasoning, when the modulation scheme is 16-QAM, 1500 slots are needed to transmit all the. bits that make up a coded block, and when the modulation scheme is 64-QAM, 1000 slots are needed to transmit all the bits that make up a coded block.
<img file="MX385274B_D0237.tif" />
232
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
The following describes the relationship between the above defined intervals and phase, as relevant to schemes for a regular phase change.
Here, five different phase change values (or phase change sets) are assumed to be ready for use in the scheme for a regular phase change, which has a period (cycle) of five. That is, the phase shifter of the transmission device of Figure 4 uses five phase shift values (or phase shift sets) P[0], P[1], P[2], P[3], yP[4] to achieve the period (cycle) of five. However, P[0] , P[l], P[2] , P[3] , and P[4] must include at least two different phase shift values (that is, P[0] , P[ l] , P[2] , P[3] , and P[4] can include identical phase shift values). (As in Figure 6, five phase shift values are needed to perform a phase shift with a period (cycle) of five on the pre-encoded baseband signal z2' only. Furthermore, as in Fig. 26, two phase shift values are needed for each interval in order to perform the phase shift on both the pre-encoded baseband signals zl' and z2'. These two phase shift values are called a phase shift set. Therefore, ideally five phase change sets should be prepared to perform a phase change with a period (cycle) of five under such circumstances). The five phase shift values (or phase shift sets) required for the period (cycle) of five are expressed as P[0] , P[l], P[2] ,
<img file="MX385274B_D0238.tif" />
233
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
P[3] , and P[4] .
For the previously described 3000 slots needed to transmit the 6000x2 bits, which constitute the coded block pair when the modulation scheme is QPSK, the phase shift value P[0] is used in the 600 slots, the phase shift value phase P[l] is used in the 600 slots, the phase shift value P[2] is used in the 600 slots, the phase shift value P[3] is used in the 600 slots, and the value of phase shift P[4] is used in the 600 intervals. This is due to the fact that any deviation in the use of the phase shift value causes great influence which should be exerted by the most frequently used phase shift value, since the receiving device depends on such an influence for the reception quality of the signal. the data.
Also, in order to transmit the first coded block, the phase shift value P[0] is used in intervals of 600 times, the phase shift value P[1] is used in intervals of 600 times, the phase shift value P[2] is used in intervals of 600 times, phase shift value P[3] is used in intervals of 600 times, and phase shift value P[4] is used at intervals of 600 times. Also, in order to transmit the second coded block, the phase shift value P[0] is used in intervals of 600 times, the phase shift value P[1] is used in intervals of 600 times, the phase shift value P[2] is used in the intervals of 600 times, the
<img file="MX385274B_D0239.tif" />
234
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY phase change value P[3] is used in the intervals of 600 times, and phase change value P[4] is used in the intervals of 600 times.
Similarly, for the previously described 1500 slots needed to transmit the 6000x2 bits that make up the coded block pair when the modulation scheme is 16-QAM, the phase shift value P[0] is used in the 300 slots, phase shift value P[l] is used in all 300 slots, phase shift value P[2] is used in all 300 slots, phase shift value P[3] is used in all 300 slots , and the phase shift value P[4] is used in the 300 slots.
Also, in order to transmit the first coded block, the phase shift value P[0] is used in intervals of 300 times, the phase shift value P[l] is used in intervals of 300 times, the phase shift value P[2] is used in the intervals of 300 times, phase shift value P[3] is used in the intervals of 300 times, and phase shift value P[4] is used at intervals of 300 times. Therefore, in order to transmit the second coded block, the phase shift value P[0] is used in intervals of 300 times, the phase shift value P[l] is used in intervals of 300 times, the phase shift value P[2] is used in the intervals of 300 times, the phase shift value P[3] is used in the intervals of 300 times, and the phase shift value P[4] is use at intervals of 300
<img file="MX385274B_D0240.tif" />
235
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY times.
Similarly, for the previously described 1000 slots needed to transmit the 6000x2 bits that make up the coded block pair when the modulation scheme is 64-QAM, the phase shift value P[0] is used in the 200 slots, phase shift value P[1] is used in all 200 slots, phase shift value P[2] is used in all 200 slots, phase shift value P[3] is used in all 200 slots , and the phase shift value P[4] is used in the 200 slots.
Also, in order to transmit the first coded block, the phase shift value P[0] is used in intervals of 200 times, the phase shift value P[1] is used in intervals of 200 times, the phase shift value P[2] is used in intervals of 200 times, phase shift value P[3] is used in intervals of 200 times, and phase shift value P[4] is used at intervals of 200 times. Also, in order to transmit the second coded block, the phase shift value P[0] is used in intervals of 200 times, the phase shift value P[1] is used in intervals of 200 times, the phase shift value P[2] is used in intervals of 200 times, phase shift value P[3] is used in intervals of 200 times, and phase shift value P[4] is used at intervals of 200 times.
As already described, the phase shift values used in the regularly changing phase shift scheme
<img file="MX385274B_D0241.tif" />
236
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY between the values of phase change with a period (cycle) of N are expressed as P [0] , P[l] ... P[N-2], P[N-1]. However, P[0], P [1]... P [N-2] , P [Nl] must include at least two different phase shift values (that is, P[0], P [ 1 ] ... P[N-2], P[N-1] can include identical values of phase shift) . In order to transmit all the bits that make up two coded blocks, the phase shift value P[0] is used in the K<sub>either</sub> intervals, the phase shift value P[1] is used in the Ki intervals, the phase shift value P[i] is used in the Ki intervals (where i = 0, 1, 2...N-1 ) , and the phase shift value P[N-1] is used in the K<sub>N</sub>_i intervals, so Condition #C19 is met.
(Condition #C19)
K<sub>either</sub> = Kj ...= Ki = ... Kn-i. That is, K.<sub>a</sub> = Kb (^ and Mo where a, b, = 0, 1, 2 ... Nl (where a and b are integers between zero and Nl) a * b) .
In order to transmit all the bits that constitute the first coded block, the phase shift value P[0] is used Ko,i times, the phase shift value P[l] is used Κχ,Ι times, the value of phase change P[i] we use Κι,ι (where i = 0, 1, 2 ... Nl, i.e. O^i^N-1, i being an integer) , and the change value of phase P[N-1] is used Kn_i,i times.
(Condition #C20)
Κο,ι = Κι,ι — Κι,ι = — Kn-i,i That is, K<sub>a</sub>,i = Kb,iy Md where a, b, = 0, 1, 2 ... Nl, a / b) .
In order to transmit all the bits that constitute
<img file="MX385274B_D0242.tif" />
237
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY the second coded block, the phase change value P[0] is used Ko<sub>/2</sub> Sometimes the phase shift value P[l] is used Ki<sub>/2</sub> Sometimes the phase shift value P[i] is used Kí<sub>/2</sub> (where i = 0, 1, 2 ... Nl, i.e. O^i^N-1, i being an integer), and the phase shift value P[N-1] Kn-i is used,<sub>2</sub> times.
(Condition #C21)
Ko,2<sup>=</sup> Κχ/2 = ... Κχ/2 = ·· Κν-ι,2· That is, Kaj2<sup>=</sup> KB,<sub>2</sub> (Vi and V> where a, b, =0, 1, 2... Nl, ab) .
Then, when a communication system that supports multiple modulation schemes selects such a supported scheme to use, Condition #C19, Condition #C20, and Condition #C21 for the supported modulation scheme should preferably be met.
However, when multiple modulation schemes are supported, each such modulation scheme typically uses symbols that transmit a different number of bits per symbol (although some may use the same number) and some modulation schemes may not satisfy Condition # C19, Condition #C20 and Condition #C21. In such a case, the following conditions apply in lieu of Condition #C19, Condition #C20, and Condition #C21.
(Condition #C22)
The difference between Ka and K<sub>b</sub> satisfies 0 or 1. That is, |Ka - Khl satisfies 0 or 1 (^, V>, where a, b = 0, 1, 2 ... Nl (where a and b are integers between 0 and Nl) a / b) .
<img file="MX385274B_D0243.tif" />
238
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY (Condition #C23)
The difference between K<sub>a</sub>,i and Kb,i satisfies 0 or 1. That is, | Ka,i - Kb,i| satisfies 0 or 1 (^h, Vd, where a, b = 0, 1, 2 ... N-1 (where a and b are integers between 0 and N-1) ab).
(Condition #C24)
The difference between K<sub>a</sub>,<sub>2</sub> and Kb,<sub>2</sub> satisfies 0 or 1. That is, |Ka,2 - Kb,2| satisfies 0 or 1 (Va, Vd, where a, b = 0, 1, 2 ... N-1 (where a and b are integers between 0 and N-1) a / b).
As already described, the offset between the phase shift values used to transmit the coded blocks is eliminated by creating a relationship between the coded block and the phase shift values. As such, the reception quality of the data can be improved by the receiving device.
In the present embodiment, N phase change values (or phase change sets) are needed in order to perform a phase change having a period (cycle) of N with the scheme for a regular phase change. As such, N phase shift values (or phase shift sets) P[0] , P[1] , P[2] ... P[N-2], and P[N-1] are prepared . However, there are schemes for ordering the phases in the established order with respect to the frequency domain. In this sense, no limitation is foreseen. The N phase shift values (or phase shift sets) P[0] , P[1] , P[2] ... P[N-2] , and P[N-1] can also change the phases of blocks in the time domain or in the domain of
<img file="MX385274B_D0244.tif" />
239
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY time-frequency to obtain a symbol arrangement as described in Modality 1. Although the preceding examples describe a phase change scheme with a period (cycle) of N, the same effects are obtainable using N phase shift values (or phase shift sets) randomly. That is, the N phase change values (or phase change sets) need not always have a regular periodicity. Provided that the conditions described above are met, high-quality improvements are achievable in the reception of the data for the receiving device.
Furthermore, given the existence of modes for spatial multiplexing MIMO schemes, MIMO schemes using a fixed precoding matrix, space-time block coding schemes, single stream transmission, and schemes using a phase shift On a regular basis, the transmitting device (broadcasting station, base station) can select any of these transmission schemes.
As described in Non-Patent Literature 3, spatial multiplexing MIMO schemes involve transmit signals si and s2 being correlated using a selected modulation scheme on each of two different antennas. MIMO schemes that use a fixed precoding matrix involve only the precoding mode (no phase shift). Additionally, space-time block coding schemes are described in Non-Patent Literature 9,
<img file="MX385274B_D0245.tif" />
240
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
16, and 17 . Single stream transmission schemes involve transmitting a si signal correlated to a selected modulation scheme from an antenna after performing predetermined processing.
Schemes using multicarrier transmission such as OFDM involve a first carrier group composed of multiple carriers and a second carrier group composed of multiple carriers different from the first carrier group, and so on, such that multicarrier transmission performed with multiple carrier groups. For each carrier group, any of the spatial multiplexing MIMO schemes, MIMO schemes using a fixed precoding matrix, space-time block coding schemes, single stream transmission, and schemes using a regular phase change. In particular, schemes using a regular phase shift in a selected (sub-)group of carriers are preferably used to perform the present embodiment.
When a phase shift, for example, a phase shift value for P[i] of X radians is performed on only a pre-encoded baseband signal, the phase shifters of Figures 3, 4, 6, 12, 25, 29, 51, and 53 multiply the precoded baseband signal z2' by e<sup>jX</sup>. So when a phase shift, say, of a phase shift set for P[i] of X radians and Y radians is performed on both baseband signals
<img file="MX385274B_D0246.tif" />
241
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY precoded, the phase shifters of figures 26, 27,
28, 52, and 54 multiply the precoded baseband signal z2 ' by e^<sup>x</sup> and multiply the pre-encoded baseband signal zl' by
DI mode
The present embodiment is first described as a variation of Mode 1. Figure 67 illustrates an exemplary transmission device pertinent to the present embodiment. Components thereof which operate identically to those in Figure 3 use the same reference numerals as therein and description thereof is omitted for simplicity below. Figure 67 differs from Figure 3 in inserting a 6702 baseband signal changer directly following the weighting units. Therefore, the following operations are primarily focused on the 6702 baseband signal changer.
Figure 21 illustrates the configuration of weighting units 3 08A and 308B. The area in Figure 21 enclosed by the dashed line represents one of the weight units. Baseband signal 307A is multiplied by wll to get wll-sl(t), and multiplied by w21 to get w21-sl(t). Similarly, baseband signal 307B is multiplied by wl2 to get wl2-s2(t), and multiplied by w22 to get w22-s2(t). Next, zl (t) = wll'sl(t) + wl2·s2(t) and z2(t)=w21-sl(t) + w22·s22(t) are obtained. Here, as explained
<img file="MX385274B_D0247.tif" />
242 in Mode 1, sl(t) and s2(t) are baseband signals modulated according to a modulation scheme such as BPSK, QPSK, 8-PSK,
16-QAM, 32-QAM, 64-QAM, 256-QAM, 16-APSK etc. Both units of
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY weighting perform the weighting using a fixed precoding matrix. The precoding matrix uses, for example, the Math 62 (formula 62) scheme, and satisfies the conditions of Math 63 (formula 63) or Math 64 (formula 64), all of which are set forth below. However, this is just an example. The value of a is not limited to Math 63 (Formula 63) and Math 64 (Formula 64), and can, for example, be 1, or it can be 0 (a is preferably a real number greater than or equal to 0, but it can also be an imaginary number).
Here, the precoding matrix is [Math 62] (formula 62)<sup>r</sup>wll ^νν21 wl2^ w22 j
<img file="MX385274B_D0248.tif" />
jo ax e J
In Math 62 (formula 62), above, a is given by:
[Mathematics 63] (formula 63)
<img file="MX385274B_D0249.tif" />
<img file="MX385274B_D0250.tif" />
243
Alternatively, in Math 62 (formula 62),
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY above, a can be given by:
[Math 64] (formula 64)
<img file="MX385274B_D0251.tif" />
Alternatively, the precoding matrix is not restricted to that of Math 62 (formula 62), but can also be:
[Math 65] (formula 65) ^wll wl2^ (a ^w21 w22 J dj where a = Ae<sup>j611</sup>, b = Be<sup>7</sup>'<sup>612</sup>, c = Ce<sup>j621</sup>, yd = De<sup>7</sup>'<sup>522</sup> . Also, one of a, b, c, and d can be equal to zero. For example: (1) a can be zero as long as b, c, and d are nonzero, (2) b can be zero as long as a, c, and d are nonzero, (3) c can be zero as long as that a, b, and d are nonzero, or (4) d can be zero as long as a, b, and e are nonzero.
Alternatively, any two of a, b, c, and d can equal zero. For example, (1) a and d can be zero as long as b and c are nonzero, or (2) b and c can be zero as long as a and d are nonzero.
When any of the modulation scheme, the
<img file="MX385274B_D0252.tif" />
244
IMPI
MEXICAN INSTITUTE OF PROPERTY OR INDUSTRIAL error correction codes, and the encoding rate thereof are changed, the precoding matrix in use can also be set and changed or the same precoding matrix can be used as it is.
Next, the baseband signal changer 6702 in Fig. 67 is described. The baseband signal changer 6702 takes the 3 weighted signal 09A and the 316B weighted signal as input, performs the baseband signal change baseband, and outputs a shifted baseband signal 67 01A and shifted baseband signal 6701B. The details of the baseband signal change are as described with reference to Fig. 55. The baseband signal switching that is performed in the present embodiment differs from that of FIG. 55 in terms of the signal used to switch. The following describes the change of the baseband signal of the present embodiment with reference to Fig. 68.
In Fig. 68, the weighted signal 3 09A(pl (i) ) has an I-phase component of I<sub>p</sub>i(i) and a quadrature component Q of Qpi(i), while the weighted signal 316B(p2(i)) has an in-phase component I of I<sub>p2</sub> (i) and a quadrature component Q of Q<sub>p2</sub>(Yo) . In contrast, the shifted baseband signal 6701A(ql (i) ) has an in-phase I component of I<sub>what</sub>i (i) and a Q quadrature component of Qqi (i) , while the shifted baseband signal 6701B(q2 (i) has an I-phase component of I<sub>q2</sub> (i) and a quadrature component Q of Q<sub>q2</sub>(Yo) . (Here, i represents (order of time or of (carrier) frequency). In the example of Figure 67, i
<img file="MX385274B_D0253.tif" />
245
IMPI
MEXICAN INSTITUTE OF PROPERTY OR INDUSTRIAL represents time, although i can also represent (carrier) frequency when Figure 67 is applied to an OFDM scheme, as in Figure 12. These points are elaborated below).
Here, the baseband components are changed by the 6702 baseband signal changer, so that:
For the shifted baseband signal ql(i), the in-phase component I can be I<sub>p</sub>i(i) while the quadrature component Q can be Q<sub>p2</sub> (i) , and for the shifted baseband signal q2(i) , the in-phase component I can be I<sub>p2</sub> (i) while the quadrature component q can be Q<sub>p</sub>i(i) . The modulated signal corresponding to a shifted baseband signal ql(i) is transmitted by transmit antenna 1 and the modulated signal corresponding to a shifted baseband signal q2(i) is transmitted from transmit antenna 2, simultaneously in a common frequency. As such, the modulated signal corresponding to a shifted baseband signal ql(i) and the modulated signal corresponding to a shifted baseband signal q2(i) are transmitted from different antennas simultaneously on a common frequency. As an alternative,
For the shifted baseband signal ql(i), the in-phase component can be I<sub>p</sub>i(i) while the quadrature component can be I<sub>p2</sub> (i) , and for the shifted baseband signal q2(i), the in-phase component can be Q<sub>pl</sub>(i) while the quadrature component can be Q<sub>p2</sub>(Yo).
<img file="MX385274B_D0254.tif" />
246
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
For the switched baseband signal ql(i), the in-phase component may be Ip2(i) while the quadrature component may be I<sub>pl</sub>(i), and for the shifted baseband signal q2(i), the in-phase component can be Q<sub>pl</sub>(i) while the quadrature component can be Q<sub>p2</sub> (Yo).
For the shifted baseband signal ql(i), the in-phase component can be I<sub>pl</sub> (i) while the quadrature component can be I<sub>p2</sub> (i) , and for the shifted baseband signal q2(i), the in-phase component can be Q<sub>p2</sub> (i) while the quadrature component can be Q<sub>pl</sub>(Yo) .
• For the shifted baseband signal ql(i), the in-phase component can be I<sub>p2</sub> (i) while the quadrature component can be I<sub>pi</sub> (i) , and for the shifted baseband signal q2(i), the in-phase component can be Q<sub>p2</sub>(i) while the quadrature component can be Q<sub>p</sub>i(i) .
• For the shifted baseband signal ql(i), the in-phase component can be I<sub>p</sub>i (i) while the quadrature component can be Q<sub>p2</sub> (i) , and for the changed baseband signal q<sub>2</sub>(i) , the in-phase component can be Q<sub>p</sub>i(i) while the quadrature component can be I<sub>p2</sub>(Yo).
For the shifted baseband signal ql(i), the in-phase component can be Q<sub>p2</sub>(i) while the quadrature component can be I<sub>p</sub>i (i) , and for the shifted baseband signal q2(i), the in-phase component can be I<sub>p2</sub>(i) while the quadrature component can be Q<sub>p</sub>i(i) .
<img file="MX385274B_D0255.tif" />
247
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
For the shifted baseband signal ql(i), the in-phase component can be Q<sub>P</sub>2(i) while the quadrature component can be I<sub>pl</sub> (i) , and for the shifted baseband signal q2(i), the in-phase component can be Q<sub>p</sub>i(i) while the quadrature component can be I<sub>p2</sub> (Yo) .
For the shifted baseband signal q2(i), the in-phase component can be I<sub>p</sub>i(i) while the quadrature component can be I<sub>p2</sub> (i) , and for the shifted baseband signal ql(i), the in-phase component can be Q<sub>p</sub>i(i) while the quadrature component can be Qp2(i) .
For the shifted baseband signal q2(i), the in-phase component can be I<sub>p2</sub>(i) while the quadrature component can be I<sub>p</sub>i(i) , and for the shifted baseband signal ql(i), the in-phase component can be Q<sub>p</sub>i(i) while the quadrature component can be Q<sub>P</sub>2(i)
For the shifted baseband signal q2(i), the in-phase component can be I<sub>p</sub>i(i) while the quadrature component can be I<sub>p2</sub> (i) , and for the shifted baseband signal ql(i), the in-phase component can be Q<sub>P</sub>2(i) while the quadrature component can be Q<sub>p</sub>i (i).
For the shifted baseband signal q2(i), the in-phase component can be I<sub>p2</sub> (i) while the quadrature component can be I<sub>p</sub>i (i) , and for the shifted baseband signal ql(i) , the in-phase component can be Q<sub>p2</sub>(i) while the quadrature component can be Q<sub>p</sub>i(i) .
<img file="MX385274B_D0256.tif" />
248
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
For the shifted baseband signal g2(i), the in-phase component can be I<sub>p</sub>i(i) while the quadrature component can be Q<sub>p2</sub> (i) , and for the shifted baseband signal ql(i), the in-phase component can be I<sub>p2</sub> (i) while the quadrature component can be Q<sub>p</sub>i(i) .
For the shifted baseband signal q2(i), the in-phase component can be I<sub>p</sub>i(i) while the quadrature component can be Q<sub>p2</sub> (i) , and for the shifted baseband signal ql(i), the in-phase component can be Q<sub>p</sub>i(i) while the quadrature component can be I<sub>p2</sub>(Yo) .
• For the shifted baseband signal q2(i), the in-phase component can be Q<sub>p2</sub> (i) while the quadrature component can be I<sub>pJ</sub> (i) , and for the shifted baseband signal ql(i), the in-phase component can be I<sub>p2</sub> (i) while the quadrature component can be Q<sub>p</sub>i(i) .
For the shifted baseband signal q2(i), the in-phase component can be Q<sub>p2</sub>(i) while the quadrature component can be I<sub>p</sub>i (i) , and for the shifted baseband signal ql(i), the in-phase component can be Q<sub>pl</sub>(i) while the quadrature component can be I<sub>p2</sub> (Yo) .
Alternatively, the weighted signals 309A and 316B are not limited to the above-described change in in-phase component and quadrature component. The change can be made in the in-phase components and in the quadrature components greater than those of the two signals.
<img file="MX385274B_D0257.tif" />
249
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Also, while the preceding examples describe the change made to baseband signals that have a common date-time ((sub-)carrier) common frequency), the baseband signals that are changed need not necessarily have a date-time. common time ((sub-)carrier) common frequency). For example, any of the following is possible.
• For the shifted baseband signal ql(i), the in-phase component can be I<sub>p</sub>i(i+v) while the quadrature component can be Q<sub>P</sub>2(i+w) , and for the shifted baseband signal q2(i) , the in-phase component can be I<sub>p2</sub>(i+w) while the quadrature component can be Q<sub>p</sub>i(i+v).
• For the shifted baseband signal ql(i), the in-phase component can be I<sub>p</sub>i(i+v) while the quadrature component can be I<sub>p2</sub>(i+w), and for the shifted baseband signal q2(i) , the in-phase component can be Q<sub>pl</sub>(i+v) while the quadrature component can be Q<sub>p2</sub>(i+w)
For the shifted baseband signal ql(i), the in-phase component can be I<sub>p2</sub>(i+w) while the quadrature component can be I<sub>p</sub>i(i+v), and for the shifted baseband signal q2 (i) , the in-phase component can be Q<sub>p</sub>i(i+v) while the quadrature component can be Q<sub>p2</sub>(i+w).
For the shifted baseband signal ql(i), the in-phase component can be I<sub>p</sub>i(i+v) while the quadrature component can be I<sub>p2</sub>(i+w), and for the shifted baseband signal q2(i) , the in-phase component can be Q<sub>p2</sub>(i+w) while
<img file="MX385274B_D0258.tif" />
250
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY that the quadrature component can be Q<sub>p</sub>i(i+v).
For the shifted baseband signal ql(i), the in-phase component can be I<sub>p2</sub>(i+w) while the quadrature component can be I<sub>pl</sub>(i+v), and for the shifted baseband signal q2(i) , the in-phase component can be Q<sub>p2</sub>(i+w) while the quadrature component can be Q<sub>p</sub>i(i+v).
For the shifted baseband signal ql(i), the in-phase component can be I<sub>pl</sub>(i+v) while the quadrature component can be Q<sub>P</sub>2(i+w), and for the shifted baseband signal q2(i), the in-phase component can be Q<sub>p</sub>i(i+v) while the quadrature component can be I<sub>p2</sub>(i+w) .
• For the shifted baseband signal ql (i), the in-phase component can be Q<sub>P</sub>2(i+w) while the quadrature component can be I<sub>pl</sub>(i+v), and for the shifted baseband signal q2(i) , the in-phase component can be I<sub>p2</sub>(i+w) while the quadrature component can be Q<sub>p</sub>i(i+v).
For the shifted baseband signal ql(i), the in-phase component can be Q<sub>p2</sub>(i+w) while the quadrature component can be I<sub>p</sub>i(i+v) , and for the shifted baseband signal q2 (i) , the in-phase component can be Q<sub>p</sub>i(i+v) while the quadrature component can be I<sub>p2</sub>(i+w) .
For the shifted baseband signal q2(i), the in-phase component can be I<sub>pl</sub>(i+v) while the quadrature component can be I<sub>p2</sub>(i+w) , and for the shifted baseband signal ql(i) , the in-phase component can be Q<sub>p</sub>i(i+v) while
<img file="MX385274B_D0259.tif" />
251
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY that the quadrature component can be Q<sub>p2</sub>(i+w).
For the shifted baseband signal q2(i), the in-phase component can be I<sub>p2</sub>(i+w) while the quadrature component can be I<sub>pl</sub>(i+v), and for the shifted baseband signal ql(i) , the in-phase component can be Q<sub>p</sub>i(i+v) while the quadrature component can be Q<sub>p2</sub>(i+w) • For the shifted baseband signal q2(i), the in-phase component can be I<sub>p</sub>i(i+v) while the quadrature component can be I<sub>p2</sub>(i+w), and for the shifted baseband signal ql(i) , the in-phase component can be Q<sub>p2</sub>(i+w) while the quadrature component can be Q<sub>p</sub>i(i+v).
• For the shifted baseband signal q2(i), the in-phase component can be I<sub>p2</sub>(i+w) while the quadrature component can be I<sub>p</sub>i(i+v), and for the shifted baseband signal ql(i) , the in-phase component can be Q<sub>p2</sub>(i+w) while the quadrature component can be Q<sub>pi</sub>(i+v).
For the shifted baseband signal q2(i), the in-phase component can be I<sub>p</sub>i(i+v) while the quadrature component can be Q<sub>p2</sub>(i+w) , and for the shifted baseband signal ql(i) , the in-phase component can be I<sub>p2</sub>(i+w) while the quadrature component can be Q<sub>p</sub>i(i+v).
For the shifted baseband signal q2(i), the in-phase component can be I<sub>p</sub>i(i+v) while the quadrature component can be Q<sub>p2</sub>(i+w), and for the shifted baseband signal ql(i) , the in-phase component can be Q<sub>p</sub>i(i+v) while
<img file="MX385274B_D0260.tif" />
252
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY that the quadrature component can be I<sub>p2</sub>(i+w).
For the shifted baseband signal q2(i), the in-phase component can be Q<sub>p2</sub>(i+w) while the quadrature component can be I<sub>p</sub>i(i+v), and for the shifted baseband signal ql(i) , the in-phase component can be I<sub>p2</sub>(i+w) while the quadrature component can be Q<sub>p</sub>i(i+v).
• For the shifted baseband signal q2(i), the in-phase component can be Q<sub>p2</sub>(i+w) while the quadrature component can be I<sub>p</sub>i(i+v), and for the shifted baseband signal ql(i) , the in-phase component can be Q<sub>pi</sub>(i+v) while the quadrature component can be I<sub>p2</sub> (i+w) .
Here, the weighted signal 309A(pl(i)) has an in-phase component I of I<sub>p</sub>i(i) and a quadrature component Q of Qpi(i), while the weighted signal 316B(p2(i)) has an in-phase component I of I<sub>p</sub>z(i) and a quadrature component Q of Q<sub>p2</sub>(Yo). You found, the shifted baseband signal 6701A (ql(i)) has an in-phase I component of I<sub>what</sub>i (i) and a quadrature Q component of Qqi (i) , while the shifted baseband signal 6701B(q2(i)) has an in-phase component I<sub>q2</sub>(i) and a quadrature component Q of Q<sub>q2</sub> (Yo) .
In Fig. 68, as already described, the weighted signal 309A(pl(i)) has an I phase component of I<sub>p</sub>i(i) and a quadrature component Q of Q<sub>p</sub>i(i), while the weighted signal 316B(p2(i)) has an in-phase component I of I<sub>p2</sub>(i) and a quadrature component Q of Q<sub>p2</sub> (Yo) . In contrast, the signal
<img file="MX385274B_D0261.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
253 baseband switched 6701A(ql(i)) has a phase I component of I<sub>what</sub>i(i) and a quadrature component Q of Q<sub>Qi</sub>(i), while the shifted baseband signal 6701B(q2(i)) has a phase I component<sub>q2</sub> (i) and a quadrature component Q of Q<sub>q2</sub> (Yo) .
As such, the phase I component of I<sub>what</sub>i (i) and the quadrature component Q of Q<sub>what</sub>i(i) of the shifted baseband signal 6701A(ql(i)) and the in-phase component I<sub>g2</sub> (i) and the quadrature component Q of Q<sub>q2</sub> (i) of the baseband signal 6701B(q2(i)) are expressible as any of the above.
As such, the modulated signal corresponding to the shifted baseband signal 6701A(ql(i)) is transmitted from the transmit antenna 312A, while the modulated signal corresponding to the shifted baseband signal 6701B(q2(i)) is transmitted from transmit antenna 312B, both being transmitted simultaneously on a common frequency. In this manner, the modulated signals corresponding to a shifted baseband signal 6701A(ql(i)) and shifted baseband signal 6701B(q2(i)) are transmitted from different antennas simultaneously on a common frequency.
Phase shifter 317B takes the shifted baseband signal 6701B and information from signal processing scheme 315 as input and regularly shifts the phase of shifted baseband signal 6701B for output. This regular change is a phase change that is done according to a predetermined phase change pattern that has a predetermined period (cycle)
<img file="MX385274B_D0262.tif" />
254
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY (eg, every n symbols (where n is an integer, n > 1) or at a predetermined interval) . The phase shift pattern is described in detail in Mode 4.
The wireless unit 310B takes the post-phase shift signal 309B as input and performs processing such as quadrature modulation, band limiting, frequency conversion, amplification, etc., then outputs the transmission signal 311B. The transmission signal 311B is then output as radio waves by an antenna 312B.
Figure 67, very similar to Figure 3, is described as having multiple encoders. However, Figure 67 can also have an encoder and a distributor like Figure 4. In such a case, the signals output by the distributor are the respective input signals for the interpolator, while the subsequent processing remains as already described. described for Figure 67, despite the changes that are thereby required.
Figure 5 illustrates an example of a time domain frame configuration for a transmission device according to the present embodiment. The token 500_l is a token for notifying the receiving device of the transmission scheme. For example, the 500_l symbol carries information such as the error correction scheme used to transmit the data symbols, the code rate of the data symbols, and the modulation scheme used to transmit the data symbols.
<img file="MX385274B_D0263.tif" />
255
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY data symbols.
Symbol 501_2 is for estimating the channel jitter for the modulated signal z2(t) (where t is the time) transmitted by the transmitting device. Symbol 502_l is a data symbol transmitted by the modulated signal zl(t) as symbol number u (in the time domain). Symbol 503_l is a data symbol transmitted by the modulated signal zl(t) as symbol number u+1.
Symbol 501_2 is for estimating the channel jitter for the modulated signal z2(t) (where t is the time) transmitted by the transmitting device. Symbol 502_2 is a data symbol transmitted by the modulated signal z2(t) as symbol number u. Symbol 503_2 is a data symbol transmitted by the modulated signal zl(t) as symbol number u+1.
Here, symbols zl(t) and z2(t) having the same date-time (identical timing) are transmitted from the transmit antenna using the same (common/shared) frequency.
The following describes the relationships between the modulated signals zl(t) and z2(t) transmitted by the transmitting device and the received signals rl(t) and r2(t) received by the receiving device.
In figure 5, 504#l and 504#2 indicate the transmission antennas of the transmission device, while 505#l
<img file="MX385274B_D0264.tif" />
256
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY and 505#2 indicate the receiving antennas of the receiving device. The transmitting device transmits the modulated signal zl(t) from the transmit antenna 504#l and transmits the modulated signal z2(t) from the transmit antenna 504#2. Here, it is assumed that the modulated signals zl(t) and z<sup>-</sup>2(t) occupy the same (common/shared) frequency (bandwidth). The channel jitters at the transmitting device antennas and receiving device antennas are hu(t), h<sub>i2</sub>(t),h<sub>2i</sub>(t), yh<sub>22</sub>(t), respectively. Assuming that the receiving device receiving antenna 505#l receives the received signal rl(t) and that the receiving device receiving antenna 505#2 receives the received signal r2(t), the following relationship holds.
[Mathematics 66] (formula 66)
<img file="MX385274B_D0265.tif" />
Fig. 69 relates to the weighting scheme (precoding scheme), the baseband shift scheme, and the phase shift scheme of the present embodiment. Weighting unit 600 is a combined version of weighting units 308A and 308B of Figure 67. As shown, current sl(t) and current s2(t) correspond to baseband signals 307A and 307B. of Figure 3. That is, the currents sl(t) and s2(t) are signals
<img file="MX385274B_D0266.tif" />
257
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY of baseband constituted by a phase I component and a quadrature Q component in accordance with the correlation made by a modulation scheme such as QPSK, 16-QAM, and 64-QAM. As indicated by the frame configuration in Figure 69, the stream sl(t) is represented as sl(u) at symbol number u, as sl(u+l) at symbol number u+1, etc. . Similarly, the current s2(t) is represented as s2(u) at symbol number u, as s2(u+l) at symbol number u+1, etc. Weighting unit 600 takes baseband signals 307A (sl(t)) and 307B (s2(t)) as well as information from signal processing scheme 315 of Fig. 67 as input, performs weighting accordingly. with the information from the signal processing scheme 315, and outputs the weighted signals 309A(pi(t)) and 316B(p2(t)) of Fig. 67.
Here, given the vector W1 = (wll,wl2) of the first row of the fixed precoding matrix F, pi(t) can be expressed as Math 67 (formula 67), below.
[Mathematics 67] (formula 67) pl(t) = Wlsl(í)
Here, given the vector W2 = (w21,w22) of the first row of the fixed precoding matrix F, p<sub>2</sub>(t) can be expressed as Math 68 (formula 68), below.
[Math 68] (formula 68) p2(t)-W2s2(t)
<img file="MX385274B_D0267.tif" />
258
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Therefore, the precoding matrix F can be expressed as follows.
[Mathematics 69] (formula 69)
<img file="MX385274B_D0268.tif" />
<img file="MX385274B_D0269.tif" />
^w21 w22 j
After the baseband signals have been switched, the switched baseband signal 6701A(qi(i)) has an in-phase I component of Iqi(i) and a Q quadrature component of Qpi(i), and the signal changed baseband 6701B (q<sub>2</sub> (i) ) has a phase I component of Iq<sub>2</sub>(i) and a Q quadrature component of Qq<sub>2</sub>(i) - The relationships between all of these are as noted above. When the phase shifter uses the phase shift formula y(t) , the postphase shift baseband signal 309B(q'<sub>2</sub>(i)) is given by Math 70 (formula 70), below.
[Math 70] (Formula 70) = y(t)q2(t)
Here, y(t) is a phase change formula that obeys a predetermined scheme. For example, given a period (cycle) of four and datetime u, the phase change formula can be expressed as Math 71 (formula 71), below.
C^IMPI
MEXICAN INSTITUTE
W * PROPERTY
INDUSTRIAL
259
[Math 71] (formula 71) yfu} = e<sup>y0</sup>
Similarly, the phase change formula for date-time u+1 can be, for example, as given by Math 72 (formula 72).
[Mathematics 72] (formula 72) . π y (u 4- 1) = e<sup>J2</sup>
That is, the phase change formula for the date-time u+k generalizes to Math 73 (formula 73). [Mathematics 73] (formula 73) . kπ y(u + k) = e<sup>J2</sup>
Note that Math 71 (Formula 71) through Math 73 (Formula 73) are given only as an example of a regular phase change.
The regular phase change is not restricted to a period (cycle) of four. Potentially, improved reception capabilities (error correction capabilities, to be exact) can be promoted in the receiving device by increasing the amount of the period (cycle) (this does not mean that a larger period (cycle) is better, although avoiding the low amounts such as two is probably ideal).
<img file="MX385274B_D0270.tif" />
260
Likewise, although Mathematics 71 (formula 71) up to the
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Mathematics 73 (formula 73) above represent a configuration in which a phase change is carried out through rotation by predetermined consecutive phases (in the formula above, each n/2), the phase change does not need to rotate in a constant amount, but can be random. For example, according to the predetermined period (cycle) of y(t), the phase can change by sequential multiplication, as shown in Math 74 (formula 74) and Math 75 (formula 75). The key point of regular phase shift is that the phase of the modulated signal changes regularly. The variance ratio of the degree of phase change is preferably as uniform as possible, such as from —π radians to n radians. However, since this describes a distribution, random variance is also possible.
[Math 74] (formula 74) ,2π .?>π ,Απ jO<sup>3</sup> < - <sup>3</sup> c<sup>3</sup> ee<sup>J</sup> —> and<sup>5</sup> —> and<sup>5</sup> —> and<sup>5</sup> —> and<sup>5</sup> .6# .Ίπ ,Ζπ .9π
[Math 75] (formula 75) ,π e<sup>2</sup> -+β<sup>ιπ</sup> .3 .5# .7 π j-π<sup>3</sup>~τ<sup>3</sup>~τ —> e<sup>4</sup> and<sup>4</sup> —+e<sup>4</sup>
<img file="MX385274B_D0271.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
261
By itself, the weighting unit 600 of Fig. 6 performs precoding using fixed and predetermined precoding weights, and the baseband signal changer performs baseband signal changing as already described, and the phase shifter changes the phase of the input signal to itself while regularly varying the degree of change.
When a specialized precoding matrix is used in the LOS environment, the reception quality is likely to be greatly improved. However, depending on direct wave conditions, the phase and amplitude components of the direct wave may differ greatly from the specialized precoding matrix, on reception. The LOS environment has certain rules. In this way, the reception quality of the data improves tremendously through a regular change of the phase of the transmission signal that obeys those rules. The present invention offers a signal processing scheme to improve the LOS environment.
Figure 7 illustrates an exemplary configuration of a receiving device 700 belonging to the present embodiment. The wireless unit 703_X receives, as input, the received signal 702_X that is received by the antenna 701_X, performs processing such as frequency conversion, quadrature demodulation, and the like, and outputs the baseband signal
704 X.
<img file="MX385274B_D0272.tif" />
262
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
The channel jitter estimator 705_l for the modulated signal zl transmitted by the transmission device takes the baseband signal 704_X as input, extracts the reference symbol 501_l for the channel estimate of Fig. 5, estimates the value of hn from Math 66 (formula 66), and outputs the channel estimation signal 706_l.
The channel jitter estimator 705_2 for the modulated signal z2 transmitted by the transmitting device takes the baseband signal 704_X as input, extracts the reference symbol 501_2 for the channel estimate of Fig. 5, estimates the value of h<sub>i2</sub> of Math 66 (formula 66), and outputs the channel estimation signal 706_2.
The wireless unit 7 03_Y receives, as input, the received signal 702_Y which is received by the antenna 701_X, performs processing such as frequency conversion, quadrature demodulation, and the like, and outputs the baseband signal 704_Y.
The channel jitter estimator 707_l for the modulated signal zl transmitted by the transmission device takes the baseband signal 704_Y as input, extracts the reference symbol 501_l for the channel estimate of Fig. 5, estimates the value of h<sub>2</sub>i of Math 66 (formula 66), and outputs the channel estimation signal 708_l.
The channel jitter estimator 707_2 for the modulated signal z2 transmitted by the transmitting device
<img file="MX385274B_D0273.tif" />
263
IMPI
MEXICAN INSTITUTE OF PROPERTY OR INDUSTRIAL takes the baseband signal 704_Y as input, extracts the reference symbol 501_2 for the channel estimation of figure 5, estimates the value of h<sub>22</sub> of Math 66 (formula 66), and outputs the channel estimation signal 708_2.
A control information decoder 709 receives baseband signal 704_X and baseband signal 704_Y as input, detects symbol 500_l indicating the transmission scheme of Fig. 5, and outputs a control scheme information signal. transmission of the transmission device 710.
A signal processor 711 takes baseband signals 704_X and 704_Y, channel estimation signals 706_1, 706_2, 708_l, and 708_2, and transmission scheme information signal 710 as input, performs detection and decoding. , and then output received data 712_1 and 712 2.
Next, the operations of the signal processor 711 of FIG. 7 are described in detail. Figure 8 illustrates an exemplary configuration of signal processor 711 pertaining to the present embodiment. As shown, the signal processor 711 is mainly made up of an inner MIMO detector, a software I/O Decoder, and a coefficient generator. Non-Patent Literature 2 and Non-Patent Literature 3 describe the iterative decoding scheme with this structure. The MIMO system described in Non-Patent Literature 2 and Non-Patent Literature 3 is a MIMO system
<img file="MX385274B_D0274.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
264 spatial multiplexing, while the present embodiment differs from Non-Patent Literature 2 and Non-Patent Literature 3 in describing a MIMO system that regularly changes phase over time, while using the precoding matrix and performing phase change. baseband signal. Taking the (channel) matrix H(t) from Math 66 (formula 66) and then letting the precoding weight matrix of Fig. 69 be F (here, a fixed precoding matrix remains unchanged for a given received signal ) and letting the phase shift formula used by the phase shifter of Fig. 69 be Y(t) (here, Y(t) changes at time t), then given the baseband signal shift, the receive vector R (t) = (rl(t),r2 (t) )<sup>T</sup>and the current vector S(t) = (if (t),s2(t))<sup>T</sup> lead to the Non-Patent Literature 2 and Non-Patent Literature 3 decoding method, which thus enables MIMO detection.
Accordingly, the coefficient generator 819 of FIG. 8 takes a transmission scheme information signal 818 (corresponding to 710 of FIG. 7) indicated by the transmission device (information to specify the fixed precoding matrix in use and the phase shift pattern used when phase is shifted) and outputs an information signal from signal processing scheme 820.
The inner MIMO detector 803 takes the information signal from the signal processing scheme 820 as input and performs iterative detection and decoding.
<img file="MX385274B_D0275.tif" />
265
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY using the signal. The operations are described below.
The processing unit illustrated in Fig. 8 uses a processing scheme, as illustrated in Fig. 10, to perform iterative decoding (iterative detection). First, detection of a code word (or a frame) of the modulated signal (current) si and a code word (or a frame) of the modulated signal (current) s2 is performed. As a result, the log-likelihood ratio of each bit of the codeword (or frame) of the modulated signal (current) si and of the codeword (or frame) of the modulated signal (current) s2 are obtained from the decoder software input/output. The log-likelihood ratio is then used to perform a second round of detection and decoding. Those operations (referred to as iterative decoding (iterative detection)) are performed multiple times. The following operations focus on creating the log-likelihood ratio of a symbol at a specific time within a frame.
In Fig. 8, a memory 815 takes baseband signal 801X (corresponding to baseband signal 704_X of Fig. 7), channel estimation group signal 802X (corresponding to channel estimation signals 706_l and 706_2 of Fig. 7), the baseband signal 801Y (corresponding to the baseband signal 704_Y of Fig. 7), and the channel estimation group signal 802Y (corresponding to the signals of
<img file="MX385274B_D0276.tif" />
266
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY channel estimation 708_l and 708_2 of Fig. 7) as input, performs iterative decoding (iterative detection), and stores the resulting matrix as a group of transformed channel signals. Memory 815 then outputs the above-described signals as needed, specifically as baseband signal 816X, channel estimate group transformed signal 817X, baseband signal 816Y, and channel estimation group transformed signal 817X. channel estimate 817Y.
Subsequent operations are described separately for initial detection and for iterative decoding (iterative detection).
Initial detection
The inner MIMO detector 803 takes the baseband signal 801X, the channel estimation group signal 802X, the baseband signal 801Y, and the channel estimation group signal 802Y as input. Here, the modulation scheme for the modulated signal (current) si and the modulated signal (current) s2 is described as 16-QAM.
The inner MIMO detector 803 first computes a candidate signal point corresponding to the baseband signal 801X from the groups of channel estimation signals 802X and 802Y. Figure 11 represents such a calculation. In Figure 11, each black dot is a candidate signal point in the IQ plane. Since the modulation scheme is 16-QAM, there are 256 candidate signal points. (However, Figure 11 is only a representation and does not indicate
<img file="MX385274B_D0277.tif" />
267
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY all 256 candidate signal points) . Letting the four transmitted bits in the modulated signal si be bO, bl, b2, and b3 and the four transmitted bits in the modulated signal s2 be b4, b5, b6, and b7, the candidate signal points corresponding to (bO, bl, b2, b3, b4, b5, b6, b7) are found in figure 11. The squared Euclidean distance between each candidate signal point and each received signal point 1101 (corresponding to baseband signal 801X) is then computed. The squared Euclidean distance between each point is divided by the noise variance or<sup>2</sup>. Therefore, we calculate E<sub>x</sub>(b0, bl, b2, b3, b4, b5, b6, b7) . That is, the squared Euclidean distance between a candidate signal point corresponding to (b0, bl, b2, b3, b4, b5, b6, b7) and a received signal point is divided by the noise variance. Here, each of the baseband signals and the modulated signals si and s2 is a complex signal.
Similarly, the inner MIMO detector 803 calculates the candidate signal points corresponding to the baseband signal 801Y from the channel estimation group signal 802X and the channel estimation group signal 802Y, computes the Euclidean distance squared between each of the candidate signal points and the received signal points (corresponding to the 801Y baseband signal), and divides the squared Euclidean distance by the noise variance c<sup>2</sup>. Therefore, we calculate E<sub>Y</sub>(b0, bl, b2, b3, b4, b5, b6, b7) . It means<sub>Y</sub> is the squared Euclidean distance between a point
<img file="MX385274B_D0278.tif" />
268
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY of candidate signal corresponding to (bO, bl, b2, b3, b4, b5, b6, b7) and a received signal point, divided by the noise variance.
Then we compute E<sub>x</sub>(b0, bl, b2, b3, b4, b5, b6, b7) + E<sub>Y</sub>(b0, bl, b2, b3, b4, b5, b6, b7) = E(b0, bl, b2, b3, b4, b5, b6, b7) .
Indoor MIMO detector 803 outputs E(b0, bl, b2, b3, b4, b5, b6, b7) as signal 804.
Log-likelihood calculator 805A takes signal 804 as input, calculates the log-likelihood of bits b0, bl, b2, and b3, and outputs log-likelihood signal 806A. Note that this log-likelihood calculation yields the one-bit log-likelihood to be 1 and the one-bit log-likelihood to be 0. The calculation is as shown in Math 28 (Formula 28), Math 29 (Formula 29), and Math 30 (Formula 30), and the details thereof are given in Non-Patent Literature 2 and 3 .
Similarly, log-likelihood calculator 805B takes signal 804 as input, calculates the log-likelihood of bits b4, b5, b6, and b7, and outputs log-likelihood signal 806A.
A de-interpolator 807A takes the log-likelihood signal 806A as input, performs a corresponding deinterpolation to that of the interpolator (interpolator 304A of FIG. 67), and outputs the log-likelihood signal 806A.
<img file="MX385274B_D0279.tif" />
269
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY log likelihood deinterpolated 808A.
Similarly, a deinterpolator 807B takes log-likelihood signal 806B as input, performs a corresponding deinterpolation to that of the interpolator (interpolator 304B of FIG. 67), and outputs deinterpolated log-likelihood signal 808B.
Log-likelihood ratio calculator 809A takes deinterpolated log-likelihood signal 808A as input, calculates the log-likelihood ratio of the bits encoded by encoder 302A of FIG. 67, and outputs log-likelihood ratio signal 810A.
Similarly, log-likelihood ratio calculator 809B takes deinterpolated log-likelihood signal 808B as input, calculates the log-likelihood ratio of the bits encoded by encoder 302B of FIG. 67, and outputs log-likelihood ratio signal 808B. log likelihood 810B.
The software I/O decoder 811A takes the log-likelihood ratio signal 810A as input, performs decoding, and outputs a decoded log-likelihood ratio 812A.
Similarly, software I/O decoder 811B takes log-likelihood ratio signal 810B as input, performs decoding, and outputs a decoded log-likelihood ratio 812B.
<img file="MX385274B_D0280.tif" />
270
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Iterative Decoding (Iterative Detection), k Iterations
The interpolator 813A takes the kth decoded log-likelihood ratio 812A decoded by the software input/output decoder as input, performs the interpolation, and outputs an interpolated log-likelihood ratio 814A. Here, the interpolation pattern used by interpolator 813A is identical to that of interpolator 304A in Figure 67.
Another interpolator (813B) takes the kth decoded log-likelihood ratio 812B decoded by the software I/O decoder as input, performs the interpolation, and outputs an interpolated log-likelihood ratio 814B. Here, the interpolation pattern used by interpolator 813B is identical to that of the other interpolator 304B of figure 67.
The indoor MIMO detector 803 takes the baseband signal 816X, the channel estimation group transformed signal 817X, the baseband signal 816Y, the channel estimation group transformed signal 817Y, the interpolated log likelihood ratio 814A, and the interpolated log likelihood ratio 814B as input. Here, 816X baseband signal, 817X channel estimation group transformed signal, 816Y baseband signal, and 817Y channel estimation group transformed signal are used instead of baseband signal
<img file="MX385274B_D0281.tif" />
271
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
801X, the 802X channel estimation group signal, the 801Y baseband signal, and the 802Y channel estimation group signal because the latter causes delays due to iterative decoding.
The iterative decoding operations of the inner MIMO detector 803 differ from the initial detection operations thereof in that the interpolated log-likelihood ratios 814A and 814B are used in the signal processing for the former. The interior MIMO detector 803 first calculates E(b0, bl, b2, b3, b4, b5, b6, b7) in the same manner as for initial detection. In addition, the coefficients for Math 11 (Formula 11) and Math 32 (Formula 32) are computed from the interpolated log-likelihood ratios 814A and 914B. The value of E(b0, bl, b2, b3, b4, b5, b6, b7) is corrected using the coefficients thus calculated to obtain E'(b0, bl, b2, b3, b4, b5, b6, b7) , which comes out as the 804 signal.
Log-likelihood calculator 805A takes signal 804 as input, calculates the log-likelihood of bits b0, bl, b2, and b3, and outputs a log-likelihood signal 806A. Note that this log-likelihood calculation yields the one-bit log-likelihood to be 1 and the one-bit log-likelihood to be 0. The calculation is as shown in Math 31 (formula 31) to Math 35 (formula 35), and details are given in the Literature
<img file="MX385274B_D0282.tif" />
272
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY of non-patents 2 and 3.
Similarly, log-likelihood calculator 805B takes signal 804 as input, calculates the log-likelihood of bits b4, b5, b6, and b7, and outputs log-likelihood signal 806B. The operations performed by the forward deinterpolator are similar to those performed for the initial detection.
While Figure 8 illustrates the configuration of the signal processor when performing iterative detection, this structure is not absolutely necessary as good reception improvements are obtained by iterative detection alone. As long as the necessary components for iterative detection are present, the configuration need not include interpolators 813A and 813B. In such a case, the inner MIMO detector 803 does not perform iterative detection.
As shown in Non-Patent Literature 5 and the like, QR decomposition can also be used to perform initial detection and iterative detection. Also, as indicated in Non-Patent Literature 11, linear operations MMSE and ZF can be performed when initial detection is performed.
Figure 9 illustrates the configuration of a different signal processor than that of Figure 8, which serves as the signal processor for the modulated signals transmitted by the transmission device of Figure 4 as shown.
<img file="MX385274B_D0283.tif" />
273
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY uses in figure 67 . The point of difference in Figure 8 is the number of software I/O decoders. A software input/output decoder 901 takes log-likelihood ratio signals 810A and 810B as input, performs decoding, and outputs a decoded log-likelihood ratio 902. A dispatcher 903 takes the decoded log-likelihood ratio 902 as input for its dispatch. Otherwise, the operations are identical to those explained in figure 8.
As already described, when a transmission device according to the present embodiment using a MIMO system transmits multiple modulated signals from multiple antennas, the change of the phase over time while being multiplied by the precoding matrix so as to change the phase regularly results in improvements in data reception quality for a receiving device in a LOS environment, where direct waves are dominant, compared to a conventional spatial multiplexing MIMO system.
In the present embodiment, and in particular in the configuration of the receiving device, the number of antennas is limited and explanations are given accordingly. However, the modality can also be applied to a large number of antennas. In other words, the number of antennas in the receiving device does not affect the operations or the advantageous effects of the present embodiment.
<img file="MX385274B_D0284.tif" />
274
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Furthermore, in the present embodiments, the encoding is not particularly limited by LDPC codes. Similarly, the decoding scheme is not limited to implementation by a software I/O decoder using sum-product decoding. The decoding scheme used by the software I/O decoder can also be, for example, the BCJR algorithm, SOVA, and the Max-Log-Map algorithm. Details are provided in Non-Patent Literature 6.
Furthermore, although the present embodiment is described using a single carrier scheme, no limitation in that regard is intended. The present mode is also applicable to multi-carrier transmission. Accordingly, the present embodiment can also be realized using, eg, spread spectrum communications, OFDM, SC-FDMA, SC-OFDM, miniwave OFDM as described in Non-Patent Literature 7, etc. Also, in the present embodiment, symbols other than data symbols, such as pilot symbols (preamble, single word, etc.) or symbols conveying control information, may be arranged within the frame in any manner.
The following describes an example where OFDM is used as a multi-carrier scheme.
Figure 70 illustrates the configuration of a transmission device using OFDM. In Figure 70, components operating in the manner described in Figures 3,
<img file="MX385274B_D0285.tif" />
275
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
12, and 67 use identical reference numerals.
An OFDM-related processor 1201A takes the weighted signal 309A as input, performs OFDM-related processing thereon, and outputs the transmission signal 1202A. Similarly, OFDM-related processor 1201B takes post-phase shift signal 309B as input, performs OFDM-related processing therein, and outputs transmission signal 1202B.
Figure 13 illustrates an exemplary configuration of OFDM-related processors 7001A and 1201B and onward from Figure 70. Components 1301A through 1310A fall between 1201A and 312A of Figure 70, while components 1301B through 1310B fall between 1201B and 312B. .
Serial-to-parallel converter 1302A performs serial-to-parallel conversion on shifted baseband signal 1301A (corresponding to shifted baseband signal 6701A of FIG. 70) and outputs parallel signal 1303A.
The reorderer 1304A takes the parallel signal 1303A as input, performs reordering on it, and outputs the reordered signal 1305A. The rearrangement is described in detail below.
The IFFT unit 1306A takes the reordered signal 1305A as input, applies an IFFT to it, and outputs the post-IFFT signal 1307A.
The 1308A wireless unit takes the signal post-IFFT
<img file="MX385274B_D0286.tif" />
276
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
1307A as input, performs processing such as frequency conversion and amplification on it, and outputs the 1309A modulated signal. The modulated signal 1309A is then output as radio waves by antenna 1310A.
Serial-to-parallel converter 1302B performs the serial-to-parallel conversion at postphase shift 1301B (corresponding to postphase shift 309B of FIG. 12) and outputs parallel signal 1303B.
Reorderer 1304B takes the parallel signal 1303B as input, performs reordering on it, and outputs the reordered signal 1305B. The rearrangement is described in detail below.
The IFFT unit 1306B takes the reordered signal 1305B as input, applies an IFFT to it, and outputs the post-IFFT signal 1307B.
The wireless unit 1308B takes the post-IFFT signal 1307B as input, performs processing such as frequency conversion and amplification on it, and outputs the modulated signal 1309B. The modulated signal 1309B is then output as radio waves by antenna 1310A.
The transmission device in Figure 67 does not use a multi-carrier transmission scheme. Thus, as shown in Fig. 69, a phase change is performed to achieve a period (cycle) of four, and the post-phase change symbols are arranged in the time domain. as the picture shows
277
70, when multi-carrier transmission such as OFDM is used, then, naturally, the symbols in the pre-encoded baseband signals that underwent a shift and a phase shift may be arranged in the time domain as in Fig.
67 and this can be applied to each (sub-)carrier. However, for multi-carrier transmission, the configuration may also be in the frequency domain, or both the frequency domain and the time domain. The following describes these settings.
Figures 14A and 14B indicate frequency on the horizontal axis and time on the vertical axis thereof and illustrate an example of a symbol reordering scheme used by reorderers 1301A and 1301B of Figure 13. The frequency axis is composed of (sub-)carriers 0 to 9. The modulated signals zl and z2 share common timestamps and use a common frequency band. Figure 14A illustrates a reordering scheme for the symbols of the modulated signal zl, while Figure 14B illustrates a reordering scheme for the symbols of the modulated signal z2. With respect to the input of the switched baseband signal symbols 13OIA to the serial to parallel converter 13 02A, the reordering is #0, #1, #2, #3, and so on. Here, since the example deals with a period (cycle) of four, #0, #1, #2, and #3 are equivalent to a period (cycle). Similarly, 25 #4n, #4n+l, #4n+2, and #4n+3 (where n is a positive integer other than
278
<img file="MX385274B_D0287.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY zero) are also equivalent to a period (cycle).
As shown in Fig. 14A, symbols #0, #1, #2, #3 and so on are arranged in order, starting at carrier 0. Symbols #0 through #9 are a given date-time $1, followed by symbols #10 to #19 which are a given date-time #2 and so on in a regular configuration. Here, the modulated signals zl and z2 are complex signals.
Similarly, with respect to the input of the weighted signal symbols 1301B to the serial to parallel converter 13 02B, the assigned reordering is #0, #1, #2, #3, and so on. Here, since the example deals with a period (cycle) of four, a different phase shift is applied to each of #0, #1, #2, and #3, where they are equivalent to one period (cycle). Similarly, a different phase shift is applied to each of #4n, #4n+l, #4n+2, and #4n+3 (where n is a nonzero positive integer), which are also equivalent to a period (cycle).
As shown in Fig. 14B, symbols #0, #1, #2, #3 and so on are arranged in order, starting at carrier 0. Symbols #0 through #9 are a given date-time $1, followed by symbols #10 to #19 which are a given date-time #2 and so on in a regular configuration.
The group of symbols 1402 shown in Fig. 14B corresponds to a period (cycle) of symbols when using
<img file="MX385274B_D0288.tif" />
279
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY the phase change scheme of figure 69. The symbol #0 is the symbol obtained using the phase in the date-time u in figure 69, the symbol #1 is the symbol obtained using the phase at date-time u+1 in figure 69, symbol #2 is the symbol obtained using the phase at date-time u+2 in figure 69, and symbol #3 is the symbol obtained using the phase at date-time u+3 in figure 69. Therefore, for any symbol #x, the symbol #x is the symbol obtained using the phase at date-time u in Figure 69 when x mod 4 is equal to 0 (that is, when the remainder of x divided by 4 is 0, where mod is the modulo operator) , the symbol #x is the symbol obtained using the phase at date-time x+1 in Figure 69 when x mod 4 is equal to , the symbol #x is the symbol obtained using the phase at date-time x+2 in figure 69 when x mod 4 is equal to 2, and the symbol #x is the symbol obtained using the phase at date-time x+3 in figure 69 when x mod 4 is equal to 3.
In the present embodiment, the zl modulated signal shown in Fig. 14A did not undergo a phase shift.
As such, when using a multicarrier transmission scheme such as OFDM, and unlike single carrier transmission, the symbols may be arranged in the frequency domain. Of course, the symbol layout scheme is not limited to those illustrated by Figs. 14A and 14B. Additional examples are shown in Figures 15A, 15B, 16A and
16B.
<img file="MX385274B_D0289.tif" />
280
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Figures 15A and 15B indicate the frequency on the horizontal axis and the time on the vertical axis thereof and illustrate an example of a symbol reordering scheme using reorderers 1301A and 1301B of Figure 13 which differs from that of Figures 14A and 14B. Figure 15A illustrates a reordering scheme for the symbols of the modulated signal zl, while Figure 15B illustrates a reordering scheme for the symbols of the modulated signal z2 . Figures 15Ά and 15B differ from Figures 14A and 14B in the reordering scheme applied to the symbols of the modulated signal zl and the symbols of the modulated signal z2 . In Fig. 15B, symbols #0 to #5 are arranged on carriers 4 to 9, symbols #6 to #9 are arranged on carriers 0 to 3, and this arrangement is repeated for symbols #10 to #19. Here, as in Fig. 14B, the symbol groups 1502 shown in Fig. 15B correspond to a period (cycle) of symbols when using the phase shift scheme of Fig. 6.
Figures 16A and 16B indicate the frequency on the horizontal axis and the time on the vertical axis thereof and illustrate an example of a symbol reordering scheme using reorderers 1301A and 1301B of Figure 13 which differs from that of Figures 14A and 14B. Figure 16A illustrates a reordering scheme for the symbols of the modulated signal zl, while Figure 16B illustrates a reordering scheme for the symbols of the modulated signal z2. Figures 16A and 16B differ
<img file="MX385274B_D0290.tif" />
281
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY of figures 14A and 14B in. that, while Figures 14A and 14B show the symbols arranged on sequential carriers, Figures 16A and 16B do not arrange the symbols on the sequential carriers. Obviously, for Figures 16A and 16B, different reordering schemes can be applied to the symbols of the modulated signal zl and the symbols of the modulated signal z2 as in Figures 15A and 15B.
Figures 17A and 17B indicate the frequency on the horizontal axis and the time on the vertical axis thereof and illustrate an example of a symbol reordering scheme using reorderers 1301A and 1301B of Figure 13 which differs from that of Figures 14A to 16B. Figure 17A illustrates a reordering scheme for the symbols of the modulated signal zl while Figure 17B illustrates a reordering scheme for the symbols of the modulated signal z2. While Figures 14A through 16B show the symbols arranged with respect to the frequency axis, Figures 17A and 17B use the frequency and time axes together in a single configuration.
While Fig. 69 describes an example where the phase change is performed in a four interval period (cycle), the following example describes an eight interval period (cycle). In Figures 17A and 17B, symbol group 1702 is equivalent to one symbol period (cycle) when using the phase shift scheme (i.e., over eight symbols) such that symbol #0 is the symbol obtained using the phase
282 at date-time u, symbol #1 is the symbol obtained using the phase at date-time u+1, symbol #2 is the symbol obtained using the phase at date-time u+2, symbol # 3 is the symbol obtained using the phase at date-time u+3, symbol #4 is the symbol obtained using the phase at date-time u+4, symbol #5 is the symbol obtained using the phase at date-time u+5, symbol #6 is the symbol obtained using the phase at date-time u+6, and symbol #7 is the symbol obtained using the phase at date-time u+7. Therefore, for any symbol #x, the symbol #x is the symbol obtained using the phase at the date-time u when x mod 8 is equal to 0, the symbol #x is the symbol obtained using the phase at the date-time time u+1 when x mod 8 is equal to 1, the symbol #x is the symbol obtained using the phase in date-time u+2 when x mod 8 is equal to 2, the symbol #x is the symbol obtained using the phase at date-time u+3 when x mod 8 is equal to 3, the symbol #x is the symbol obtained using the phase at date-time u+4 when x mod 8 is equal to 4 , the symbol #x is the symbol obtained using the phase at date-time u+5 when x mod 8 equals 5, the symbol #x is the symbol obtained using the phase at date-time u+6 when x mod 8 equals 6, and the symbol #x is the symbol obtained using the phase at date-time hour u+7 when x mod 8 is equal to 7. In Figs. 17A and 17B four slots along the time axis and two slots along the frequency axis are used for a total of 4 x 2 = 8 slots, where one symbol period (cycle) is arranged. Here, mxn symbols given by
<img file="MX385274B_D0291.tif" />
283
IMPI
period (cycle) (that is, mxn different phases are available for multiplication), then n intervals (carriers) in the frequency domain and m intervals in the time domain must be used to arrange the symbols of each period (cycle), such that m > n. This is because the phase of direct waves fluctuates slowly in the time domain relative to the frequency domain. Therefore, the present embodiment performs a regular phase shift that reduces the influence of uniform direct waves. Thus, the period (cycle) of phase change should preferably reduce the fluctuations of direct waves. Therefore, m must be greater than n. Taking the above into consideration, using the time and frequency domains together for the rearrangement, as shown in Figures 17A and 17B, is preferable to using either the frequency domain alone or the time domain as a consequence of the strong probability that the direct waves become regular. As a result, the effects of the present invention are more easily obtained. However, the rearrangement in the frequency domain can lead to a diversity gain due to the fact that the frequency domain fluctuations are abrupt. As such, the use of the frequency and time domains together are not always ideal for rearrangement.
Figures 18A and 18B indicate the frequency on the horizontal axis and the time on the vertical axis thereof and illustrate an example of a symbol rearrangement scheme using
<img file="MX385274B_D0292.tif" />
284
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY the rearrangers 1301A and 1301B of Figure 13 which differs from that of Figures 17A and 17B. Figure 18A illustrates a reordering scheme for the symbols of the modulated signal zl, while Figure 18B illustrates a reordering scheme for the symbols of the modulated signal z2. Very similar to Figures 17A and 17B, Figures 18A and 18B illustrate the use of the time and frequency axes together. However, in contrast to Figures 17A and 17B, where the frequency axis is prioritized and the time axis is used for the secondary symbol pattern, Figures 18A and 18B prioritize the time axis and use the frequency axis for the secondary symbol configuration. In FIG. 18B, symbol group 1802 corresponds to a symbol period (cycle) when the phase shift scheme is used.
In Figures 17A, 17B, 18A, and 18B, the reordering scheme applied to the symbols of the modulated signal zl and the symbols of the modulated signal z2 may be identical or may differ as in Figures 15A and 15B. Either approach allows a good reception quality to be obtained. Also, in Figures 17A, 17B, 18A, and 18B, the symbols may be arranged non-sequentially as in Figures 16A and 16B. Either approach allows a good reception quality to be obtained.
Figure 22 indicates the frequency on the horizontal axis and the time on the vertical axis thereof and illustrates an example of a symbol rearrangement scheme using the
<img file="MX385274B_D0293.tif" />
IMPI
MEXICAN INSTITUTE
OF THE PROPERTY
INDUSTRIAL
285 reorderers 1301A and 1301B of figure 13 which differs from the previous one. Figure 22 illustrates a regular phase shift scheme using four intervals, similar to the date-time ua u+3 of Figure 69. The characteristic feature of Figure 22 is that although ! the symbols are reordered with respect to the frequency domain, when read along the time axis, a periodic variation of the n symbols is evident (η = 1 in the example of FIG. 22). The frequency domain symbol group 2210 in Figure 22 indicates four symbols to which the phase shifts in date-time ua u+3 of Figure 6 are applied.
Here, symbol #0 is obtained using the phase shift at datetime u, symbol #1 is obtained using the phase shift at datetime u+1, symbol #2 is obtained using the phase shift phase at date-time u+2, and symbol #3 is obtained using the phase shift at date-time u+3.
Similarly, for the domain symbol group . of frequency 2220, symbol #4 is obtained using the phase shift at date-time u, symbol #5 is obtained using the phase shift at date-time u+1, symbol #6 is obtained using the phase shift at date-time u+2, and symbol #7 is obtained using the phase shift at date-time u+3.
The phase change described above is applied to the symbol at date-time $1. However, in order to apply a periodic variation with respect to the time domain, the following phase shifts are applied to the groups of symbols
<img file="MX385274B_D0294.tif" />
For the group of time-domain symbols 2201, symbol #0 is obtained using the phase shift at date-time u, symbol #9 is obtained using the phase shift at
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
286
2201, 2202, 2203, and 2204.
datetime u+1, symbol #18 is obtained using the phase shift in datetime u+2, and symbol #27 is obtained using the phase shift in datetime u+3.
For the group of time-domain symbols 2202, symbol #28 is obtained using the phase shift in the date-time u<sub>Y</sub> symbol #1 is obtained using the phase shift at datetime u+1, symbol #10 is obtained using the phase shift at datetime u+2, and symbol #19 is obtained using the shift of phase at date-time u+3.
For the 2203 time-domain symbol group, symbol #20 is derived using the phase shift at date-time u, symbol #29 is derived using the phase shift at date-time u+1, the symbol #2 is obtained using the phase shift at date-time u+2, and symbol #11 is obtained using the phase shift at date-time u+3.
For the 2204 time-domain symbol group, symbol #12 is derived using the phase shift at date-time u, symbol #21 is derived using the phase shift at date-time u+1, the symbol #3 0 is obtained using the phase shift at date-time u+2, and symbol #3 is obtained using the phase shift at date-time u+3.
<img file="MX385274B_D0295.tif" />
287
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
The characteristic feature of Figure 22 is seen by taking symbol #11 as an example, where the two symbols neighboring it along the frequency axis (#10 and #12) both change symbols using a different phase than symbol # 11, and where the two symbols neighboring it that have the same carrier in the time domain (#2 and #20) switch both symbols using a different phase than symbol #11. This is true not only for symbol #11, but also for any symbol that has two neighboring symbols in the frequency domain and the time domain. Therefore, the phase change is effectively carried out. It is highly probable that this improves the reception quality of the data since the influence of the regularization of the direct waves is less prone to the reception.
Although Figure 22 illustrates an example where n = 1, the invention is not limited in this way. The same can be applied to a case where n = 3. Furthermore, although Figure 22 illustrates the embodiment of the effects described above by arranging the symbols in the frequency domain and advancing in the time domain so as to achieve the characteristic effect of imparting a periodic variation in the order of arrangement of the symbols, the symbols can also be arranged randomly (or regularly) with the same effect.
Although the present embodiment describes a variation of embodiment 1 in which a baseband signal changer is inserted before the phase change, the present embodiment also
<img file="MX385274B_D0296.tif" />
288
IMPI
MEXICAN INSTITUTE OF PROPERTY OR INDUSTRIAL can be realized as a combination with mode 2, such that the baseband signal changer is inserted before the phase change in figures 26 and 28. Therefore, in figure 26, phase shifter 317A takes the shifted baseband signal 6701A(qi(i)) as input, and phase shifter 317B takes the shifted baseband signal 6701B(q<sub>2</sub>(i)) as input. The same applies to the phase shifter 317A and 317B of figure 28.
The following describes a scheme that allows the receiving device to obtain a good received signal quality for the data without taking into account the disposition of the receiving device considering the location of the receiving device with respect to the transmitting device.
Figure 31 illustrates an example of frame configuration for a portion of the symbols within a signal in the time-frequency domains, giving a transmission scheme where a regular phase shift is performed for a multi-carrier scheme such as OFDM.
Figure 31 illustrates the frame configuration of the modulated signal z2' corresponding to the shifted baseband signal input to the phase shifter 317B of Figure 67. Each square represents a symbol (although both signals si and s2 are included). for precoding purposes, depending on the precoding matrix, only one of the signals can be used
<img file="MX385274B_D0297.tif" />
289
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY yes and s2) .
Consider symbol 3100 on carrier 2 and date-time $2 in Figure 31. The carrier described here may alternatively be referred to as a subcarrier.
Within carrier 2, there is a very strong correlation between the channel conditions for symbol 610A on carrier 2, date-time $2, and the channel conditions for the nearest neighbor symbols in the time domain at date-time. time $2, that is, symbol 3013 at datetime $1 and symbol 3101 at datetime $3 within carrier 2.
Similarly, for datetime $2, there is a very strong correlation between the channel conditions for symbol 3100 on carrier 2, datetime $2, and the channel conditions for the nearest neighbor symbols in the domain of frequency to carrier 2, that is, symbol 3104 on carrier 1, date-time $2, and symbol 3104 on date-time $2, carrier 3.
As described above, there is a very strong correlation between the channel conditions for symbol 3100 and the channel conditions for each symbol 3101, 3102, 3103, and 3104.
The present description considers N different phases (where N is an integer, N 2 ) for multiplication in a transmission scheme where the phase is regularly changed. The symbols illustrated in
<img file="MX385274B_D0298.tif" />
290
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY in figure 31 are indicated as ejO, eg. This means that this symbol is the signal z2 ' of figure 6 that underwent a phase change through multiplication by ejO. That is, the values given for the symbols in figure 31 are the value of y(t) as it appears in Math 70 (equation 70).
The present embodiment takes advantage of the high correlation in channel conditions that exists between neighboring symbols in the frequency domain and/or neighboring symbols in the time domain in a symbol arrangement that allows for high quality reception of signals. data that is obtained by the receiving device that receives the symbols of the post-phase change.
In order to achieve this high quality of data reception, conditions #D1-1 and #Dl-2 should preferably be met.
(Condition #D1-1)
As shown in Fig. 69, for a transmission scheme involving a regular phase shift being performed on the shifted baseband signal q2 using a multi-carrier scheme such as OFDM, time X, carrier Y is a symbol to transmit data (hereinafter data symbol), neighboring symbols in the time domain, i.e. at time Xl, carrier Y and at time X+l, carrier Y are all data symbols, and a different phase change is
<img file="MX385274B_D0299.tif" />
291
IMPI
The MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY must perform on the changed baseband signal q2 corresponding to each of these three data symbols, that is, on the changed baseband signal q2 at time X, the carrier Y, at time Xl, carrier Y and at time X+l, carrier Y.
(Condition #Dl-2)
As shown in Fig. 69, for a transmission scheme involving a regular phase shift being performed on the shifted baseband signal q2 using a multi-carrier scheme such as OFDM, time X, carrier Y is a symbol to transmit data (hereinafter data symbol), neighboring symbols in the time domain, i.e. at time X, carrier Y+l and at time X, carrier Yl are all data symbols, and a different phase shift must be performed on the shifted baseband signal q2 corresponding to each of these three data symbols, i.e., on the shifted baseband signal q2 at time X, carrier Y, at time time X, carrier Yl and at time X, carrier Y+l.
Ideally, a data symbol should satisfy Condition #D1-1. Similarly, the data symbols must satisfy Condition #Dl-2.
The reasons that justify Conditions #D1-1 and #Dl-2 are the following.
A very strong correlation exists between the channel conditions of a given symbol of a transmission signal (hereinafter symbol A) and the channel conditions of
<img file="MX385274B_D0300.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
292 the symbols neighboring symbol A in the time domain, as described above.
Therefore, when the three neighboring symbols in the time domain each have a different phase, then, despite the degradation of the reception quality in the LOS environment (poor signal quality caused by the degradation of the conditions as a consequence of the phase relationships despite the high signal quality in terms of SNR) for symbol A, the remaining two symbols neighboring symbol A have a high probability of providing good reception quality. As a result, a good received signal quality is achieved after error correction and decoding.
Similarly, there is a very strong correlation between the channel conditions of a given symbol of a transmission signal (symbol A) and the channel conditions of symbols neighboring symbol A in the frequency domain, as described above.
Therefore, when three neighboring symbols in the frequency domain each have a different phase, then despite the degradation of the reception quality in the LOS environment (poor signal quality caused by the degradation of the conditions as a consequence of the direct wave phase relationships despite high signal quality in terms of SNR) for symbol A, the remaining two symbols neighboring symbol A have a high probability of providing good quality
<img file="MX385274B_D0301.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
293 of reception. As a result, a good received signal quality is achieved after error correction and decoding.
By combining Conditions #D1-1 and #Dl-2, an even higher data reception quality can probably be achieved for the receiving device. Therefore, the following Condition #Dl-3 can be derived.
(Condition #Dl-3)
As shown in Fig. 69, for a transmission scheme involving a regular phase shift being performed on the shifted baseband signal q2 using a multi-carrier scheme such as OFDM, time X, carrier Y is a symbol for transmitting data (data symbol), neighboring symbols in the time domain, i.e. at time Xl, carrier Y and at time X+l, carrier Y are also data symbols, fifteen and neighboring symbols in the frequency domain, i.e. at time X, carrier Yl and at time X, carrier Y+l are also data symbols, such that a different phase shift would be what is performed on the shifted baseband signal q2 corresponding to each of these five data symbols, 20 i.e. on the shifted baseband signal q2 at time X, carrier Y, at time X, carrier Yl , at time X, the carrier Y+l, at time Xl, carrier Y and at time X+l, carrier Y.
Here, the different phase changes are the following 25. Phase shifts are defined between 0 radians
294 and 2Π radians. For example, for time X, carrier Y, a phase shift of is applied to the pre-encoded baseband signal q<sub>2</sub> From Figure 69, for time Xl, carrier Y, a phase shift of is applied to the pre-encoded baseband signal q<sub>2</sub> of figure 69, for time X+l, carrier Y, a phase shift of e<sup>jax+1,Y</sup> is applied to the precoded baseband signal q2 of Figure 69 such that 0 £ θχ,γ < 2Π, 0 θχ-ι,γ < 2Π, and 0 < θχ+ι,γ < 2Π, all units they are radians. And for Condition #D1-1, it follows that θχ,γ ^θχ-ι,γ, θχ,γ /θχ+ι,γ, and that θχ-ι,γ / θχ+ι,γ Similarly, for Condition #Dl-2, follows that θχ,γ / θχ,γ-i, θχ,γ / θχ,γ+ι, and that θχ,γ_ι / θχ,γ+ι And for Condition #Dl-3, follows that θχ,γ / θχ-ι,γ, θχ,γ / θχ+ι,γ, θχ,γ / θχ,γ_ι, θχ,γ / θχ,γ+χ, θχ-1,γ / θχ+Ι, Υ, θχ-ι,γ / θχ,Υ<sup>-</sup>1, θχ-Ι,Υ / θχ,Υ+1, θχ+Ι,Υ / θχ,Υ-1, θχ+Ι,Υ / θΧ,Υ+1, and that θχ,γ_ι / θχ,γ+ι.
Ideally, a data symbol should satisfy Condition #D1-1.
Figure 31 illustrates an example of Condition #Dl-3, ' where symbol A corresponds to symbol 3100. The symbols are arranged such that the phase by which the shifted baseband signal q2 of Figure 69 is multiplied it differs for symbol 3100, for both symbols neighbors of it in the time domain 3101 and 3102, and for both symbols neighbors of it in the frequency domain 3102 and 3104. Therefore, despite the degradation of the quality of the received signal of the 3100 symbol for the receiver, a good quality is highly probable.
<img file="MX385274B_D0302.tif" />
295
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY signal for neighboring signals, thus guaranteeing good signal quality after error correction.
Figure 32 illustrates a symbol arrangement obtained through phase shifts under these conditions.
It is evident from Figure 32, with respect to any data symbol, that a different phase shift is applied for each neighboring symbol in the time domain and in the frequency domain. As such, the ability of the receiving device to correct errors can be improved.
In other words, in Fig. 32, when all neighboring symbols in the time domain are data symbols, Condition #D1-1 holds for all X's and all Y's.
Similarly, in Figure 32, when all neighboring symbols in the frequency domain are data symbols, Condition #Dl-2 holds for all X's and all Y's.
Similarly, in Figure 32, when all neighboring frequency-domain symbols are data symbols and all neighboring time-domain symbols are data symbols, Condition #Dl-3 holds for all X and all the Y's
The following describes the example described above for a case where the phase shift is performed on two shifted baseband signals ql and q2 (see Fig. 68).
Various phase shift schemes are applicable to perform a phase shift on two shifted baseband signals.
<img file="MX385274B_D0303.tif" />
IMPI MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
296 ql and q2. The details thereof will be explained below.
Scheme 1 involves a phase shift of the shifted baseband signal q2 as described above, to achieve the phase shift illustrated by Figure 32. In Figure 32, a phase shift having a period (cycle) of ten is applied to the shifted baseband signal q2 . However, as described above, in order to satisfy Conditions #D1-1, #Dl-2, and #Dl-3, the phase shift applied by the shifted baseband signal q2 at each (sub-) carrier changes over time. (Although such changes are applied in Figure 32 with a period (cycle) of ten, other phase change schemes are also applicable). Then, as shown in Fig. 33, the degree of phase shift that is made to the shifted baseband signal q2 produces a constant value that is one tenth of the phase shift that is made to the shifted baseband signal q2. In Fig. 33, for a period (cycle) (of phase shift performed on the shifted baseband signal q2) including date-time $1, the value of phase shift performed on the shifted baseband signal changed base ql is e-'<sup>0</sup>. Then, for the next period (cycle) (of phase shift that is performed on the shifted baseband signal q2) that includes date-time $2, the value of the degree of phase shift that is performed on the shifted baseband signal precoded base ql is e<sup>9</sup>^<sup>3</sup>, and so on.
The symbols illustrated in figure 33 are indicated for example as e<sup>j0</sup>. This means that this symbol is the sign
<img file="MX385274B_D0304.tif" />
297
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY ql of figure 26 that underwent a phase change through multiplication by e<sup>j0</sup>.
As shown in Figure 33, the phase shift applied to the shifted baseband signal ql produces a constant value that is one tenth of the phase shift of that performed on the preencoded shifted baseband signal q2 such that the change of the post-phase value varies with the number of each period (cycle). (As described above, in Figure 33, the value is e<sup>j0</sup> for the first period (cycle), for the second period (cycle), and so on).
As described above, the phase shift that is performed on the shifted baseband signal q2 has a period (cycle) of ten, but the period (cycle) can be effectively made larger than ten by taking the degree of phase shift applied to the shifted baseband signal ql and the shifted baseband signal q2 in consideration. Accordingly, the data reception quality for the receiving device can be improved.
Scheme 2 involves a phase shift of the shifted baseband signal q2 as described above, to achieve the phase shift illustrated by Figure 32. In Figure 32, a phase shift having a period (cycle) of ten is applied to the shifted baseband signal q2 . However, as described above, in order to satisfy Conditions #D1-1, #Dl-2, and #Dl-3, the phase shift applied to the baseband signal
<img file="MX385274B_D0305.tif" />
298
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY changed q2 in each (sub-)carrier changes over time. (Although such changes are applied in Fig. 32 with a period (cycle) of ten, other phase change schemes are also applicable). Then, as shown in Fig. 33, the phase shift that is performed on the shifted baseband signal q2 produces a constant value that is one tenth of that performed on the shifted baseband signal q2.
The symbols illustrated in figure 30 are indicated for example as e<sup>i0</sup>. This means that this symbol is the shifted baseband signal ql that underwent a phase shift through multiplication by e<sup>j0</sup>.
As described above, the phase shift that is performed on the shifted baseband signal q<sub>2</sub> has a period (cycle) of ten, but the period (cycle) can be effectively made larger than ten by taking the phase shifts applied to the shifted baseband signal ql and the shifted baseband signal q2 into consideration. Accordingly, the data reception quality for the receiving device can be improved. An effective way to apply scheme 2 is to perform a phase shift on the shifted baseband signal ql with a period (cycle) of N and perform a phase shift on the precoded baseband signal q2 with a period (cycle) of M such that N and M are prime to each other. As such, taking both the shifted baseband signals ql and q2 into consideration, a period (cycle) of NxM is easily achieved by doing
<img file="MX385274B_D0306.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
299 effectively greater than the period (cycle) when N and M are prime to each other.
While the foregoing describes an example of the phase change scheme described above, the present invention is not so limited. The phase shift can be performed with respect to the frequency domain, the time domain, or in time-frequency blocks. Similar improvements in data reception quality can be obtained for the receiving device in all cases.
The same also applies to frames having a different configuration than described above where pilot symbols (SP Symbols) and symbols carrying control information are inserted between data symbols. The details of the phase change under such circumstances are as follows.
Figures 47A and 47B illustrate the frame configuration of the modulated signals (qlyq2 shifted baseband signals) zl or zl' and z2' in the time-frequency domain. Figure 47A illustrates the frame configuration of the modulated signal (ql shifted baseband signal) zl or zl' while Figure 47B illustrates the frame configuration of the modulated signal (q2 shifted baseband signal) z2'. In Figures 47A and 47B, 4701 marks the pilot symbols while 47 02 marks the data symbols. The data symbols 4702 are symbols in which the change or the change and the phase change can be performed.
<img file="MX385274B_D0307.tif" />
300
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Figures 47A and 47B, similar to Figure 69, indicate the arrangement of the symbols when a phase shift is applied to the shifted baseband signal q2 (while no phase shift is performed on the shifted baseband signal q2). ql) . (Although Figure 69 illustrates a phase shift with respect to the time domain, the shift of time t with carrier f in Figure 69 corresponds to a phase shift with respect to the frequency domain. In other words, replacing (t) with (t, f) where t is time and f is frequency corresponds to performing a phase shift in the time-frequency blocks). Therefore, the numerical values indicated in Figs. 47A and 47B for each of the symbols are the values of the changed baseband signal q2 after the phase change. No values are given for the symbols of the shifted baseband signal ql(zl) of Figs. 47A and 47B since there was no phase shift therein.
The important point of FIGS. 47A and 47B is that the phase shift is performed on the data symbols of the shifted baseband signal q2, that is, on the symbols that underwent precoding or precoding and shifting. (The symbols under discussion, which are preencoded, actually include both si and s2 symbols). Therefore, no phase shift is performed on the pilot symbols inserted at z2'.
Figures 48A and 48B illustrate the framing of the modulated signals (baseband signals switched
<img file="MX385274B_D0308.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
301 ql and q2) zl or zl' and z2 ' in the time-frequency domain. Figure 48A illustrates the frame configuration of the modulated signal (ql shifted baseband signal) zl or zl' while Figure 48B illustrates the frame configuration of the modulated signal (q2 shifted baseband signal) z2'. In Figures 48A and 48B, 4701 marks the pilot symbols while 4702 marks the data symbols. Data symbols 4702 are symbols on which precoding or precoding and a phase shift is performed.
Figures 48A and 48B indicate the arrangement of the symbols when a phase shift is applied to the shifted baseband signal ql and the shifted baseband signal q2. Therefore, the numerical values indicated in Figs. 48A and 48B for each of the symbols are the values of changed baseband signals ql and q2 after the phase change.
The important point of Figures 48A and 48B is that the phase shift is performed on the data symbols of the changed baseband signal ql, that is, on the precoded or precoded and changed symbols thereof, and on the data symbols of the changed baseband signal ql. data of the changed baseband signal q2, ie, in the pre-coded or pre-coded and changed symbols thereof. (The symbols under discussion, which are preencoded, actually include both si and s2 symbols). Therefore, no phase shift is performed on the pilot symbols inserted in zl', nor on the pilot symbols inserted in z2'.
<img file="MX385274B_D0309.tif" />
302
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Figures 49A and 49B illustrate the frame configuration of the modulated signals (switched baseband signals ql and q2) zl or zl' and z2' in the time-frequency domain. Figure 49A illustrates the frame configuration of the modulated signal (ql shifted baseband signal) zl or zl' while Figure 49B illustrates the frame configuration of the modulated signal (q2 shifted baseband signal) z2'. In Figures 49A and 49B, 4701 marks the pilot symbols, 4702 marks the data symbols, and 4901 marks the null symbols for the in-phase component of the baseband signal I = 0 and the quadrature component Q = 0. As such, data symbols 4702 are symbols on which precoding or precoding and a phase shift is performed. Figures 49A and 49B differ from Figures 47A and 47B in the configuration scheme for symbols other than data symbols. The time and carriers at which the pilot symbols are inserted in the modulated signal zl' are null symbols in the modulated signal z2'. Conversely, the time and carriers on which the pilot symbols are inserted in the modulated signal z2' are null symbols in the modulated signal zl'.
Figures 49A and 49B, which are similar to Figure 69, indicate the arrangement of the symbols when a phase shift is applied to the shifted baseband signal q2 (while no phase shift is performed on the baseband signal q2). base changed ql) . (Although Figure 69 illustrates a phase shift with respect to the time domain, the shift of time t with carrier f in
<img file="MX385274B_D0310.tif" />
303
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY Figure 6 corresponds to a phase shift with respect to the frequency domain. In other words, replacing (t) with (t, f) where t is time and f is frequency corresponds to performing a phase shift in the time-frequency blocks). Therefore, the numerical values indicated in Figs. 49A and 49B for each of the symbols are the values of the changed baseband signal q<sub>2</sub> after the phase change. No values are given for the symbols of the shifted baseband signal ql of Figs. 49A and 49B since there was no phase shift therein.
The important point of Figs. 49A and 49B is that the phase shift is performed on the data symbols of the shifted baseband signal q2, that is, on the symbols that underwent precoding or precoding and shifting. (The symbols under discussion, which are preencoded, actually include both si and s2 symbols). Therefore, no phase shift is performed on the pilot symbols inserted at z2'.
Figures 50A and 50B illustrate the framing of the modulated signals (switched baseband signals ql and q2) zl or zl' and z2' in the time-frequency domain. Figure 50A illustrates the frame configuration of the modulated signal (ql shifted baseband signal) zl or zl' while Figure 50B illustrates the frame configuration of the modulated signal (q2 shifted baseband signal) z2'. In Figures 50A and 50B, 4701 marks the pilot symbols, 4702 marks the data symbols, and 4901 marks the null symbols for the in-phase component of the band signal.
<img file="MX385274B_D0311.tif" />
304
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY base I = 0 and quadrature component Q = 0. As such, data symbols 4702 are symbols on which precoding or precoding and a phase shift is performed. Figures 50A and 50B differ from Figures 43A and 48B in the configuration scheme for symbols other than data symbols. The time and carriers at which the pilot symbols are inserted in the modulated signal zl' are null symbols in the modulated signal z2'. Conversely, the time and carriers on which the pilot symbols are inserted in the modulated signal z2' are null symbols in the modulated signal zl'.
Figures 50A and 50B indicate the arrangement of the symbols when a phase shift is applied to the shifted baseband signal ql and the shifted baseband signal q2 . Therefore, the numerical values indicated in Figs. 50A and 50B for each of the symbols are the values of changed baseband signals ql and q2 after a phase change.
The important point of Figures 50A and 50B is that a phase shift is performed on the data symbols of the changed baseband signal ql, that is, on the precoded or precoded and shifted symbols thereof, and on the data symbols of the changed baseband signal ql. data of the changed baseband signal q2, ie, in the pre-coded or pre-coded and changed symbols thereof. (The symbols under discussion, which are preencoded, actually include both si and s2 symbols). Therefore, no phase shift is performed on the pilot symbols inserted in zl', nor
<img file="MX385274B_D0312.tif" />
305
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY in the pilot symbols inserted in z2' .
Fig. 51 illustrates an exemplary configuration of a transmission device that generates and transmits the modulated signal having the frame configuration of Figs. 47A, 47B, 49A, and 49B. Components therein that perform the same operations as those in Figure 4 use the same reference symbols as therein. Figure 51 does not include a baseband signal changer as illustrated in Figures 67 and 70. However, figure 51 can also include a baseband signal changer between the weighting units and the phase shifter, much like figures 67 and 70.
In Figure 51, the weighting units 3 08A and 308B, the phase shifter 317B, and the baseband signal shifter only operate at the times indicated by the frame pattern signal 313 as corresponding to the data symbols .
In Fig. 51, a pilot symbol generator 5101 (which also generates null symbols) outputs baseband signals 5102A and 5102B for a pilot symbol whenever frame signal pattern 313 indicates a pilot symbol (and a pilot symbol). null).
Although not indicated in the frame configuration of Figs. 47A to 50B, when precoding (and a phase rotation) is not performed, such as when
<img file="MX385274B_D0313.tif" />
306
IMPI
MEXICAN INSTITUTE OF PROPERTY OR INDUSTRIAL transmits a modulated signal using only one antenna (so that the other antenna does not transmit a signal) or when using a space-time coding transmission scheme (in particular, space-time block coding). ) to transmit the control information symbols, then the frame signal configuration 313 takes the control information symbols 5104 and the control information 5103 as input. When the frame signal pattern 313 indicates a symbol of the control information, the baseband signals 5102A and 5102B thereof are output.
Wireless units 310A and 310B in FIG. 51 take multiple baseband signals as input and select a desired baseband signal according to the configuration of frame signal 313. Wireless units 310A and 310B then apply signal processing. OFDM signal and outputs modulated signals 311A and 31IB that conform to the frame configuration.
Figure 52 illustrates an exemplary configuration of a transmission device that generates and transmits the modulated signal having the frame configuration of Figures 48A, 48B, 50A, and 50B. Components therein that perform the same operations as those in Figure 4 use the same reference symbols as therein. Figure 52 shows an additional phase shifter 317A that operates only when the frame signal pattern 313 indicates a symbol of
<img file="MX385274B_D0314.tif" />
307
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY data. At all other times, the operations are identical to those described for Figure 51. Figure 52 does not include a baseband signal changer as illustrated in Figures 67 and 70. However, Figure 52 may also include a baseband signal shifter between the weighting unit and the phase shifter, very similar to figures 67 and 70.
Figure 53 illustrates an exemplary configuration of a transmission device that differs from that of Figure 51. Figure 53 does not include a baseband signal changer as illustrated in Figures 67 and 70. However, Figure 53 can also include a baseband signal shifter between the weighting unit and the phase shifter, much like Figures 67 and 70. The following describes the points of difference. As shown in FIG. 53, phase shifter 317B takes multiple baseband signals as input. Then, when the framing signal pattern 313 indicates a data symbol, the phase shifter 317B performs the phase shift on the pre-encoded baseband signal 316B. When the frame signal pattern 313 indicates a pilot symbol (or a null symbol) or a control information symbol, the phase shifter 317B stops phase shift operations such that the frame signal symbols baseband are output as is. (This can be interpreted as a forced rotation corresponding to e<sup>j0</sup>) .
A 5301 selector takes the multiple band signals
<img file="MX385274B_D0315.tif" />
308
IMPI
MEXICAN INSTITUTE OF PROPERTY OR INDUSTRIAL base as input and selects a baseband signal having a symbol indicated by the frame signal pattern 313 for output.
Figure 54 illustrates an exemplary configuration of a transmission device that differs from that of Figure 52. Figure 54 does not include a baseband signal changer as illustrated in Figures 67 and 70. However, Figure 54 can also include a baseband signal shifter between the weighting unit and the phase shifter, much like Figures 67 and 70. The following describes the points of difference. As shown in FIG. 54, phase shifter 317B takes multiple baseband signals as input. Then, when the framing signal pattern 313 indicates a data symbol, the phase shifter 317B performs the phase shift on the pre-encoded baseband signal 316B. When the frame signal pattern 313 indicates a pilot symbol (or a null symbol) or a control information symbol, the phase shifter 317B stops phase shift operations such that the frame signal symbols baseband are output as is. (This can be interpreted as a forced rotation corresponding to e<sup>30</sup>) .
Similarly, as shown in Figure 54, phase shifter 5201 takes multiple baseband signals as input. Then, when the frame signal pattern 313 indicates a data symbol, the phase shifter 5201 performs
<img file="MX385274B_D0316.tif" />
309
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY the phase shift in the 309A pre-encoded baseband signal. When the frame signal pattern 313 indicates a pilot symbol (or a null symbol) or a control information symbol, the phase shifter 5201 stops phase shift operations such that the frame signal symbols baseband are output as is. (This can be interpreted as a forced rotation corresponding to e<sup>j0</sup>) .
The above explanations are given using the pilot symbols, control symbols, and data symbols as examples. However, the present invention is not limited in this way. When symbols are transmitted using schemes other than precoding, such as single antenna transmission or transmission using space-time block coding, the absence of phase shift is important. Conversely, performing the phase shift on symbols that were pre-encoded is the key point of the present invention.
Therefore, a characteristic feature of the present invention is that the phase change is not performed on all symbols within the frame configuration in the time-frequency domain, but is performed only on the baseband signals that are transmitted. precoded and experienced change.
The following describes a scheme for regularly changing the phase when encoding is performed using block codes as described in Non-Patent Literature 12 to 15, such as QC LDPC Codes (not only QC-LDPC can be used
<img file="MX385274B_D0317.tif" />
310
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY but also LDPC codes, concatenated LDPC and BCH codes, Turbo-codes or Duo-Binary Turbo-codes that use tail bits, and so on. The following example considers a case where two streams si and s2 are transmitted. When encoding is performed using the block codes and control information and the like are not necessary, the number of bits that make up each encoded block coincides with the number of bits that make up each block code (the control information and so on). described below has yet to be included). When encoding using block codes or the like is performed and control information or the like (for example, CRC transmission parameters) is necessary, then the number of bits that make up each encoded block is the sum of the number of bits that composes the block codes and the number of bits that composes the information.
Figure 34 illustrates the varying amounts of symbols and intervals required in two coded blocks when block codes are used. For example, unlike Figures 69 and 70, Figure 34 illustrates the varying amounts of symbols and intervals needed in each coded block when block codes are used when, for example, two streams si and s2 are transmitted as indicated in Figure 4, with a decoder and distributor. (Here, the transmission scheme can be any single carrier scheme or a multi-carrier scheme such as OFDM).
<img file="MX385274B_D0318.tif" />
311
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
As shown in Figure 34, when block codes are used, there are 6000 bits that make up a single encoded block. In order to transmit these 6000 bits, the number of symbols required depends on the modulation scheme: 3000 for QPSK, 1500 for 16-QAM, and 1000 for 64-QAM.
Then, since the transmission device described above transmits two streams simultaneously, 1500 of the aforementioned 3000 symbols that are needed when the modulation scheme is QPSK are assigned to si and the other 1500 symbols are assigned to s2 . As such, 1500 slots are required to transmit the 1500 symbols (hereafter, slots) for each of si and s2 .
Using the same reasoning, when the modulation scheme is 16-QAM, 750 slots are needed to transmit all the bits that make up a coded block, and when the modulation scheme is 64-QAM, 500 slots are needed to transmit all the bits that make up a coded block. make up a coded block.
The following describes the relationship between the previously defined intervals and the multiplication phase, as it relates to the schemes for a regular phase change. Here, five different phase shift values (or phase shift sets) are supposed to be prepared for use in the scheme for a regular phase shift. That is, the phase shifter of the transmission device described above uses five
<img file="MX385274B_D0319.tif" />
312
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY phase change values (or phase change sets) to achieve the period (cycle) of five. (As in Fig. 69, five phase shift values are needed in order to perform a phase shift having a period (cycle) of five on the shifted baseband signal q2 alone. Similarly, in order to phase shift both q and q2 shifted baseband signals, two phase shift values are needed for each slot. These two phase shift values are called the phase shift set. Therefore, here, in order to perform a phase change having a period (cycle) of five, five such phase change sets must be prepared). The five phase shift values (or phase shift sets) are expressed as PHASE [0] , PHASE [1] , PHASE [2] , PHASE[3], and PHASE[4].
For the 1500 slots described above required to transmit the 6000 bits that make up a single coded block when the modulation scheme is QPSK, PHASE[0] is used for 300 slots, PHASE[1] is used for 300 slots, PHASE [2] is used in 300 slots, PHASE[3] is used in 300 slots, and PHASE[4] is used in 300 slots. This is due to the fact that any deviation in the use of the phase causes the most frequently used phase to exert a great influence and that the receiving device depends on such influence for the reception quality of the data.
Also, for the 750 intervals described
<img file="MX385274B_D0320.tif" />
313
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY previously required to transmit the 6000 bits that make up a single coded block when the modulation scheme is 16-QAM, PHASE[0] is used in 150 slots, PHASE[1] is used in 150 slots , PHASE[2] is used in 150 slots, PHASE[3] is used in 150 slots, and PHASE[4] is used in 150 slots.
Furthermore, for the 500 slots described above needed to transmit the 6000 bits that make up a single coded block when the modulation scheme is 64-QAM, PHASE[0] is used in 150 slots, PHASE[1] is used in 100 slots, PHASE[2] is used for 100 slots, PHASE[3] is used for 100 slots, and PHASE[4] is used for 100 slots.
As described above, a scheme for a regular phase change requires the preparation of N phase change values (or phase change sets) (where the N different phases are expressed as PHASE[0], PHASE[1 ], PHASE [2] ... PHASE[N-2] , PHASE [N-1] ) . As such, in order to transmit all the bits that make up a single coded block, PHASE[0] is used in K<sub>either</sub> intervals, PHASE [1] is used in Ki intervals, PHASE [i] is used in Ki intervals (where i = 0, 1, 2...N-1) , and PHASE[N-1] is used in K<sub>N</sub>~i intervals, so as to satisfy Condition #Dl-4.
(Condition #Dl-4)
K<sub>either</sub> = Ki ...= Ki = ... Κν-í. That is, K.<sub>a</sub> =K<sub>b</sub> (for Va and Vb
<img file="MX385274B_D0321.tif" />
314
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY where a, b, =0, 1, 2 ... Nl, ab) .
Then, when a communication system that supports multiple modulation schemes selects to use one of the supported schemes, Condition #Dl-4 is preferably met for the supported modulation scheme.
However, when multiple modulation schemes are supported, typically each such modulation scheme uses symbols that transmit a different number of bits per symbol (although some may use the same number), Condition #Dl-4 may not be met for some modulation schemes. In such a case, the following condition applies instead of Condition #Dl-4.
(Condition #Dl-5)
The difference between K<sub>a</sub> and K<sub>b</sub> satisfies 0 or 1. That is, | Ka-K<sub>b</sub>| satisfies 0 or 1 (Va, Vb, where a, b = 0, 1, 2 ... Nl, that is, 0^a,b^Nl, a and b being integers, ab)
Figure 35 illustrates the varying amounts of symbols and intervals required in two coded blocks when block codes are used. Figure 35 illustrates the varying amounts of symbols and intervals needed in each coded block when block codes are used when, for example, two streams si and s2 are transmitted as indicated by the transmission device of Figure 67 and Figure 70 , and the transmitting device has two encoders. (Here, the transmission scheme can be any carrier scheme
<img file="MX385274B_D0322.tif" />
315
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY single or multi-carrier scheme such as OFDM).
As shown in Figure 35, when block codes are used, there are 6000 bits that make up a single encoded block. In order to transmit these 6000 bits, the number of symbols required depends on the modulation scheme, it is 3000 for QPSK, 1500 for 16-QAM, and 1000 for 64-QAM.
The transmission device of Figure 67 and the transmission device of Figure 70 each transmit two streams at a time and have two encoders. As such, each of the two streams transmits different blocks of code. Therefore, when the modulation scheme is QPSK, two coded blocks from si and s2 are transmitted within the same slot, eg transmit a first coded block from si, then transmit a second coded block from s2. As such 3000 slots are necessary in order to transmit the first and second coded blocks.
Using the same reasoning, when the modulation scheme is 16-QAM, 1500 slots are needed to transmit all the bits that make up the two coded blocks, and when the modulation scheme is 64-QAM, 1000 slots are needed to transmit all the bits that make up the two coded blocks. bits that make up the two coded blocks.
The following describes the relationship between the previously defined intervals and the multiplication phase,
<img file="MX385274B_D0323.tif" />
316
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY as it relates to schemes for a regular phase change.
Here, five different phase shift values (or phase shift sets) are supposed to be prepared for use in the scheme for a regular phase shift. That is, the phase shifter of the transmission device of Figure 67 and Figure 67 uses five phase shift values, (or phase shift sets) to achieve the period (cycle) of five. (As in Fig. 69, five phase shift values are needed in order to perform a phase shift having a period (cycle) of five only on the shifted baseband signal q2 . Similarly, in order To perform the phase shift on both the shifted baseband signals ql and q2, two phase shift values are required for each slot These two phase shift values are called the phase shift set. Therefore, here, in order to perform a phase change having a period (cycle) of five, five such phase change sets must be prepared). The five phase shift values (or phase shift sets) are expressed as PHASE [0] , PHASE [1] , PHASE [2] , PHASE[3], and PHASE[4].
For the 3000 slots described above needed to transmit the 6000x2 bits that make up the two coded blocks when the modulation scheme is QPSK, PHASE[0] is used for 600 slots, PHASE[1] is used for 600 slots, PHASE [2] is used in 600 steps, PHASE [3] is used in 600 steps, and PHASE[4] is used in 600 steps.
<img file="MX385274B_D0324.tif" />
317
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
This is due to the fact that any deviation in the use of the phase causes the most frequently used phase to exert a great influence and that the receiving device depends on such influence for the reception quality of the data.
Also, in order to transmit the first coded block, PHASE[0] is timed 600 times, PHASE[1] is timed 600 times, PHASE[2] is timed 600 times , PHASE [3] is used in the intervals 600 times, and PHASE [4] is used in the intervals 600 times . Also, in order to transmit the second coded block, PHASE[0] is used in intervals 600 times, PHASE[1] is used in intervals 600 times, PHASE[2] is used in intervals 600 times , PHASE [3] is used in intervals 600 times, and PHASE [4] is used in intervals 600 times.
Similarly, for the 1500 slots described above needed to transmit the 6000x2 bits that make up the two coded blocks when the modulation scheme is 16-QAM, PHASE[0] is used in 300 slots, PHASE[1] is used in 300 slots, PHASE[2] is used in 300 slots, PHASE[3] is used in 300 slots, and PHASE[4] is used in 300 slots.
Also, in order to transmit the first coded block, PHASE[0] is timed 300 times, PHASE[1] is timed 300 times, PHASE[2] is timed 300 times , the PHASE [3] is used in the intervals
<img file="MX385274B_D0325.tif" />
318
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
00 times, and PHASE [4] is used in the intervals 3 00 times. Also, in order to transmit the second coded block, PHASE[0] is timed 300 times, PHASE[1] is timed 300 times, PHASE[2] is timed 300 times , PHASE [3] is used in intervals 300 times, and PHASE [4] is used in intervals 300 times.
Similarly, for the 1000 slots described above needed to transmit the 6000x2 bits that make up the two coded blocks when the modulation scheme is 64-QAM, PHASE[0] is used in 200 slots, PHASE[1] is used in 200 slots, PHASE[2] is used in 200 slots, PHASE[3] is used in 200 slots, and PHASE[4] is used in 200 slots.
Also, in order to transmit the first coded block, PHASE[0] is timed 200 times, PHASE[1] is timed 200 times, PHASE[2] is timed 200 times , PHASE [3] is used in the intervals 200 times, and PHASE [4] is used in the intervals 200 times. Also, in order to transmit the second coded block, PHASE[0] is timed 200 times, PHASE[1] is timed 200 times, PHASE[2] is timed 200 times , PHASE [3] is used in the intervals 200 times, and PHASE [4] is used in the intervals 200 times.
As described above, a scheme for a regular phase change requires the preparation of N values of
<img file="MX385274B_D0326.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY phase change (or phase change sets) (where the N different phases are expressed as PHASE[0], PHASE[1], PHASE [2] ... PHASE[N -2] , the PHASE[Nl] ) . As such, in order to transmit all the bits that make up a single coded block, PHASE[0] is used in K<sub>either</sub> intervals, the PHASE [1] is used in K<sub>x</sub> intervals, PHASE[i] is used on Ki intervals (where i = 0, 1, 2..JN-1) , and PHASE[N-1] is used on K<sub>N</sub>_<sub>X</sub> intervals, in order to comply with Condition #Dl-6.
(Condition #Dl-6)
K<sub>either</sub> = Ki ...= Ki = ... Ktr-i. That is, K.<sub>a</sub> =K<sub>b</sub> (for Va and Vd where a, b, =0, 1, 2 ... Nl, a Ψ b) .
Also, in order to transmit all the bits that make up the first encoded block, the PHASE[0] K is used<sub>0</sub>,i times, PHASE [1] is used Κι,ι times, PHASE [i] is used Ki,i times (where i = 0, 1, 2..N-1, i.e. 0^í^Nl , i being an integer), and the PHASE [Nl] is used Kn-x,! times, so as to meet Condition #Dl-7.
(Condition #Dl-7)
Κο,ι<sup>=</sup> Κι,ι<sup>=</sup> ... Ki<x = ... Kn-i,i That is, Ka/i<sup>=</sup> KbíX (^^ and Mo where a, b, =0, 1, 2 ... Nl, ab) .
Also, in order to transmit all the bits that make up the second encoded block, the PHASE[0] K is used<sub>0/2</sub> Sometimes, the PHASE[1] is used K<sub>1/2</sub> Sometimes the PHASE[i] is used K<sub>i<2</sub> times (where i = 0, 1, 2...N-1, i.e. 0^ííN-l, i being an integer) , and the PHASE [Nl] is used Kn_i<sub>/2</sub> times, in order to fulfill the Condition
<img file="MX385274B_D0327.tif" />
320
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY #Dl-8.
(Condition #Dl-8)
Kq,2<sup>=</sup> Ki,2 = — Ki<sub>/2</sub> = — Kn-i,2 That is, K<sub>a/2</sub> = Kb,2 and Va where a, b, =0, 1, 2... Nl, ab) .
Thus, when a communications system that supports multiple modulation schemes selects to use one of the supported schemes, Condition #Dl-6, Condition #Dl-7, and Condition #Dl-8 are all met preferentially for the modulation scheme admitted.
However, when multiple modulation schemes are supported, typically each such modulation scheme uses symbols that transmit a different number of bits per symbol (although some may use the same number), Condition #Dl-6 Condition #Dl-7, and Condition #Dl-8 may not be met for some modulation schemes.
In such a case, the following conditions apply instead of Condition #Dl-6, Condition #Dl-7, and Condition #Dl-8.
(Condition #Dl-9)
The difference between K<sub>a</sub> and K<sub>b</sub> satisfies 0 or 1. That is, | Ka - Kb| satisfies 0 or 1 (Va, Vb, where a, b = 0, 1, 2 ... Nl, that is, 0<a,b^Nl, a and b being integers, a Ψ b) (Condition #D1-1O)
The difference between K<sub>a</sub>,i and K<sub>b/1</sub> satisfies 0 or 1. That is, |Ka,i - K<sub>br</sub>i| satisfies 0 or 1 (Va, Vb, where a, b = 0, 1, 2 ... Nl, 25 i.e. 0^a,b^Nl, a and b being integers, a / b)
<img file="MX385274B_D0328.tif" />
321
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY (Condition #D1-11)
The difference between K<sub>a</sub>,<sub>2</sub> and Kb,<sub>2</sub> satisfies 0 or 1. That is, | Ka,<sub>2</sub> - Kb.sl satisfies 0 or 1 (Va, Vb, where a, b = 0, 1, 2 ... Nl,
3, to 0 b)
As described above, the offset between the phases that are used to transmit the encrypted blocks is eliminated by creating a relationship between the encrypted block and the multiplication phase. As such, the reception quality of the data for the receiving device can be improved.
As described above, the N phase change values (or phase change sets) are needed in order to perform a phase change having a period (cycle) of N with the scheme for regular phase change. As such, prepare the N phase shift values (or phase shift sets), PHASE[0] , PHASE [1] , PHASE[2] ... PHASE[N-2] , and the PHASE[Nl]. However, there are schemes to order the phases in the fixed order with respect to the frequency domain. No limitation is intended in this regard. The N phase shift values (or phase shift sets), the PHASE[0], the PHASE[1], the PHASE[2] ... the PHASE[N-2] , and the PHASE[Nl] they can also change the phases of the blocks in the time domain or in the time-frequency domain to obtain an arrangement of the symbols. Although the examples above describe a phase change scheme with a period (cycle) of N, the same effects are obtained using N phase change values (or sets).
<img file="MX385274B_D0329.tif" />
322
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY phase change) randomly. That is, the N phase change values (or phase change sets) need not always have a regular periodicity. Provided that the conditions described above are satisfied, great quality improvements are achievable in the reception of the data for the receiving device.
Furthermore, given the existence of modes for spatial multiplexing MIMO schemes, MIMO schemes using a fixed precoding matrix, space-time block coding schemes, single stream transmission, and schemes using regular phase shift , the transmitting device (broadcasting station, base station) can select any of these transmission schemes.
As described in Non-Patent Literature 3, spatial multiplexing MIMO schemes involve transmission signals si and s2 that are correlated using a selected modulation scheme on each of two different antennas. MIMO schemes that use a fixed precoding matrix involve only the precoding mode (no phase shift). Additionally, space-time block coding schemes are described in Non-Patent Literature 9, 16, and 17. Single stream transmission schemes involve a transmission signal correlated to a selected modulation scheme from an antenna after predetermined processing.
<img file="MX385274B_D0330.tif" />
323
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Schemes using multicarrier transmission such as OFDM involve a first carrier group composed of multiple carriers and a second carrier group composed of multiple carriers different from the first carrier group, and so on, such that multicarrier transmission performed with multiple carrier groups. For each carrier group, any of the spatial multiplexing MIMO schemes, MIMO schemes using a fixed precoding matrix, space-time block coding schemes, single stream transmission, and schemes using a regular phase change. In particular, schemes using a regular phase shift in a selected (sub-)group of carriers are preferably used to accomplish the above.
Although the present description describes the present embodiment as a transmission device applying precoding, baseband shift, and phase shift, all of these can be variously combined. In particular, the phase shifter described for the present embodiment can be freely combined with the phase shifter described in all other embodiments.
D2 modality
The present embodiment describes a phase change initialization scheme for the regular phase change that is described throughout the present description. this scheme
<img file="MX385274B_D0331.tif" />
324
IMPI
MEXICAN INSTITUTE OF PROPERTY OR INDUSTRIAL initialization is applicable to the transmission device of Figure 4 when using a multi-carrier scheme such as OFDM, and for the transmission devices of Figures 67 and 70 when using a single decoder and distributor, similar to figure 4.
The following is also applicable to a scheme for regularly changing the phase when encoding is performed using block codes as described in Non-patent Literature 12 to 15, such as QC LDPC Codes (not only QC-LDPC can be used but also LDPC codes), concatenated LDPC and BCH codes, Turbo-Codes or Duo-Binary Turbo-Codes using tail bits, and so on.
The following example considers a case where two currents si and s2 are transmitted. When encoding is performed using the block codes and control information and the like are not necessary, the number of bits that make up each encoded block coincides with the number of bits that make up each block code (the control information and so on). described below has yet to be included). When encoding is performed that requires the use of block codes or the like and control information or the like is necessary (for example, CRC transmission parameters), then the number of bits that make up each encoded block is the sum of the number of bits that make up the block codes and the number of bits that make up the information.
<img file="MX385274B_D0332.tif" />
325
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Figure 34 illustrates the varying amounts of symbols and intervals required in each encoded block when block codes are used. Figure 34 illustrates the varying amounts of symbols and intervals required in each coded block when block codes are used when, for example, two streams si and s2 are transmitted as indicated by the transmission device described above and the transmission device has a single decoder. (Here, the transmission scheme can be either a single-carrier scheme or a multi-carrier scheme such as OFDM).
As shown in Figure 34, when block codes are used, there are 6000 bits that make up a single encoded block. In order to transmit these 6,000 bits, the number of symbols required depends on the modulation scheme: 3,000 for QPSK, 1,500 for 16-QAM, and 1,000 for 64-QAM.
Then, since the transmission device described above transmits two streams simultaneously, 1500 of the aforementioned 3000 symbols that are needed when the modulation scheme is QPSK are assigned to si and the other 1500 symbols are assigned to s2 . As such, 1500 slots are required to transmit the 1500 symbols (hereafter, slots) for each of si and s2 .
Using the same reasoning, when the modulation scheme is 16-QAM, 750 slots are needed to transmit all the bits that make up a coded block and
<img file="MX385274B_D0333.tif" />
326
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY When the modulation scheme is 64-QAM, 500 intervals are necessary to transmit all the bits that make up a coded block.
The following describes a transmission device that transmits modulated signals having a frame configuration illustrated in Figs. 71A and 71B. Figure 71Ά illustrates a frame configuration for the modulated signal zl' or zl (transmitted by antenna 312A) in the time and frequency domains. Similarly, Figure 71B illustrates a frame configuration for modulated signal z2 (transmitted by antenna 312B) in the time and frequency domains. Here, the frequency (band) used by the modulated signal zl' or zl and the frequency (band) used for the modulated signal z2 are identical, carrying the modulated signals zl' or zl and z2 at the same time.
As shown in FIG. 71A, the transmitting device transmits a preamble (control token) during interval A. The preamble is a token that conveys control information for a communication partner. In particular, this preamble includes information on the modulation scheme used to transmit a first and second coded block. The transmitting device transmits the first coded block during interval B. The transmitting device then transmits the second coded block during interval C.
In addition, the transmitting device transmits a
<img file="MX385274B_D0334.tif" />
327
IMPI
MEXICAN INSTITUTE OF PROPERTY OR INDUSTRIAL preamble (control token) during interval D. The preamble is a token that conveys control information to a communication partner. In particular, this preamble includes information on the modulation scheme used to transmit a third or fourth coded block and so on. The transmitting device transmits the third coded block during interval E. The transmitting device then transmits the fourth coded block during interval D.
Also, as shown in Fig. 71B, the transmitting device transmits a preamble (control token) during interval A. The preamble is a token that conveys control information for a communication partner. In particular, this preamble includes information on the modulation scheme used to transmit a first and second coded block. The transmitting device transmits the first coded block during interval B. The transmitting device then transmits the second coded block during interval C.
In addition, the transmitting device transmits a preamble (control token) during the interval D. The preamble is a token that conveys control information to a communication partner. In particular, this preamble includes information on the modulation scheme used to transmit a third or fourth coded block and so on. The transmitting device transmits the third coded block
<img file="MX385274B_D0335.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY during interval E. The transmitting device then transmits the fourth coded block during interval D.
Figure 72 indicates the number of slots used when transmitting the coded blocks of Figure 34, specifically using 16-QAM as the modulation scheme for the first coded block. Here, 750 slots are needed to transmit the first coded block.
Similarly, Figure 72 also indicates the number of slots used to transmit the second coded block, using QPSK as the modulation scheme thereof. Here, 1500 slots are needed to transmit the second coded block.
Figure 73 indicates the slots used when transmitting the coded blocks of Figure 34, specifically using QPSK as the modulation scheme for the third coded block. Here, 1500 slots are needed to transmit the encrypted block.
As explained throughout this description, the modulated signal zl, that is, the modulated signal transmitted by the antenna 312A, does not experience a phase shift, while the modulated signal z2, that is, the modulated signal transmitted by the 312B antenna, does not experience a phase shift. The following phase change scheme is used for figures 72 and 73.
Before the phase change occurs, seven different phase change values are prepared. The seven exchange values
<img file="MX385274B_D0336.tif" />
329
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY phases are labeled #0, #1, #2, #3, #4, #5, #6, and #7. The phase change is regular and periodic. In other words, the phase shift values are applied regularly and periodically such that the order is #0, #1, #2, #3, #4, #5, #6, #0, #1, # 2, #3, #4, #5, #6, #0, #1, #2, #3, #4, #5, #6 and so on.
As shown in Fig. 72, since 750 slots are needed for the first coded block, the phase shift value #0 is initially used, such that #0, #1, #2, #3, #4 , #5, #6, #0, #1, #2 ... #3, #4, #5, #6 are used in succession with the interval 750 using #0 in the final position.
The phase shift is then applied to each slot for the second coded block. The present description assumes broadcast and multicast transmission applications. As such, a receiving terminal may have no need for the first encrypted block and extract only the second encrypted block. In such circumstances, since the final slot used for the first coded block uses the phase shift value #0, the initial phase shift value used for the second coded block is #1. As such, the following schemes are conceivable:
(a): the aforementioned terminal monitors the transmission of the first coded block, i.e. it monitors the pattern of phase shift values throughout the final interval used to transmit the first coded block, and then estimates the phase shift value used for the initial interval
<img file="MX385274B_D0337.tif" />
330
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY of the second codified block;
(b): (a) does not occur and the transmitting device transmits the information about the phase shift values in use in the initial interval of the second coded block. Scheme (a) leads to higher power consumption by the terminal due to the need to monitor the transmission of the first encrypted block. However, scheme (b) leads to lower data transmission efficiency.
Accordingly, there is a need to improve the phase shift value assignment described above. A scheme is considered in which the phase shift value used to transmit the initial interval of each coded block is fixed. Thus, as indicated in Fig. 72, the phase shift value used to transmit the initial interval of the second coded block and the phase shift value used to transmit the initial interval of the first coded block are identical, #0 being.
Similarly, as indicated in Figure 73, the phase shift value used to transmit the initial slot of the third coded block is not #3, but instead is identical to the phase shift value used to transmit the initial slot of the first and second coded blocks, being #0.
As such, the problems accompanying both schemes (a) and (b) described above can be restricted
<img file="MX385274B_D0338.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY while retaining the effects thereof.
In the present embodiment, the scheme used to initialize the phase shift value for each coded block, ie, the phase shift value used for the initial interval of each coded block, is fixed to be #0. However, other schemes for single frame units can also be used. For example, the phase shift value used for the initial interval of a symbol transmitting information after the preamble or control symbol is transmitted may be set to #0.
D3 mode
The above-described embodiments describe a weighting unit that uses a precoding matrix expressed in complex numbers for precoding. However, the precoding matrix can also be expressed in real numbers.
That is, it is assumed that two baseband signals si (i) and s2(i) (where i is time or frequency) are correlated (using a modulation scheme) and precoded to obtain precoded baseband signals zl( i) and z2(i) . As such, the correlated baseband signal si(i) has an in-phase component of I<sub>sl</sub>(i) and a quadrature component of Q<sub>s</sub>i(i) , and the baseband correlated signal s2(i) has an in-phase component of I<sub>s2</sub> (i) and a quadrature component of Q<sub>AND</sub>2<i) ,
<img file="MX385274B_D0339.tif" />
332
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY whereas the precoded baseband signal zl(i) has an in-phase component of Izl(i) and a quadrature component of Q<sub>zl</sub>(i), and the precoded baseband signal z2(i) has an in-phase component of I<sub>z2</sub>(i) and a quadrature component of Q<sub>z2</sub> (i) , which gives the following precoding matrix H<sub>r</sub> when all values are real numbers.
[Mathematics 76] (Equation 76)
<img file="MX385274B_D0340.tif" />
The precoding matrix H<sub>r</sub> can also be expressed as follows, where all values are real numbers.
[Mathematics 77] (Equation 77)
<td> 20</td><td>hr</td><td>a<sub>or</sub> #21</td><td> #12 #22</td><td> #13 #23</td><td> #14 #24</td>
<td></td><td></td><td> #31 <#41</td><td> #32 #42</td><td> #33 #43</td><td>#3. 4 LCm)</td>
where an, ai<sub>2</sub>, aj.3,<sup>a</sup>i4/e<sub>2</sub>i, to<sub>22</sub>, a<sub>2</sub>3, to<sub>2</sub>4 / a.31, ^32? ^33» ^34, ^41/ ^42/ to<sub>43</sub>, Already<sub>44</sub> they are real numbers. However, none
<img file="MX385274B_D0341.tif" />
333
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY of the following can maintain: {an=0, a<sub>12</sub>=0, oh<sub>3</sub> = 0, yay<sub>4</sub> = 0}, {a<sub>2i</sub>=0, ^22=0/ ^23=0, already<sub>24</sub>=0}, {to<sub>33</sub>=0, to<sub>32</sub>=0, 333=0, and 334=0}, and {a4i=0, 342=0, a<sub>43</sub>=0, yeah<sub>44</sub>=0}. Also, none of the following can hold: {311 = 0, ^21-0/<sup>a</sup>3i=0, yeah<sub>4</sub>i=o}, {^12=0, 322=0, 3<sub>32</sub> = 0, already<sub>42</sub> = or}, {a<sub>33</sub> = 0, at<sub>23</sub>=0, 3<sub>33</sub>=0, yeah<sub>43</sub>=0}, and {3i<sub>4</sub>=0, to<sub>24</sub>=0, to<sub>34</sub>=0, and 3<sub>44</sub>=0}.
Modality The
The present embodiment describes a transmission scheme as an application of phase shifting to pre-encoded signals (or pre-encoded signals having shifted base bands) for a broadcast system using the DVB-T2 (Digital Video Broadcast for Broadcasting System) standard. second-generation digital terrestrial television broadcasting). First, the configuration of a frame in a broadcast system using the DVB-T2 standard is described.
Figure 74 illustrates the global frame configuration of a signal transmitted by a broadcasting station using the DVB-T2 standard. Since DVB-T2 uses an OFDM scheme, the frame is configured in the time-frequency domain. Thus, Figure 74 illustrates the frame configuration in the time-frequency domain. The frame includes P1 signaling data (7401), L1 pre-signaling data (7402), L1 post-signaling data (7403), a common PLP (physical layer pipe) (7404), and PLP #1 to #N (7405_l to 7405_N) . (Here, the L1 presignaling data (74 02) and the L1 postsignaling data (7403) are called P2 symbols). As such,
<img file="MX385274B_D0342.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY the signaling data P1 (7401), the pre-signalling data L1 (7402), the post-signalling data Ll (7403), a common PLP (physical layer pipe) (7404), and the PLP #1 to #N (7405_l to 7405_N) form a frame, which is called a T2 frame, thus constituting a frame configuration unit.
Signaling data P1 (7401) is a symbol used by the receiving device for signal detection and frequency synchronization (including frequency offset estimation), which simultaneously serves to convey information such as size of FFT and whether the modulated signal is transmitted by a SISO or MISO scheme. (With SISO schemes, only one modulated signal is transmitted, while with MISO schemes, multiple modulated signals are transmitted. In addition, the space-time blocks described in Non-Patent Literature 9, 16, and 17 can be used ).
The L1 presignaling data (7402) is used to transmit the information related to the schemes used to transmit the frame, concerning the guard interval, the information of the signal processing scheme used to reduce the PAPR (Peak to Average Power Ratio). ) , the modulation scheme used to transmit the Ll post-signaling data, the FEC scheme, its coding rate, the length and size of the Ll post-signaling data, them the payload pattern, the specific cell numbers (frequency region) and depending on whether a normal mode or a
<img file="MX385274B_D0343.tif" />
335
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY extended mode (if normal mode and extended mode differ in terms of number of subcarriers used to transmit the data).
Post-signaling data L1 (7403) is used to transmit such information as the number of PLPs, the frequency region in use, the specific numbers of PLPs, the modulation scheme used to transmit the PLPs, the FEC scheme, the code rate of the same and the number of blocks transmitted by each PLP and so on.
The common PLP (7404) and PLPs #1 to #N (7405_l to 7405_N) are areas used for data transmission.
The frame configuration of Figure 74 illustrates P1 signaling data (7401), L1 pre-signaling data (7402), L1 post-signaling data (7403), common PLP (physical layer pipe) (7404) , and PLPs #1 to #N (7405_l to 7405_N) divided with respect to the time domain for transmission. However, two or more of these signals can occur simultaneously. Figure 75 illustrates one such case. As shown, the L1 presignalling data, the L1 postsignalling data and the common PLP occur at the same date-time, while PLP#1 and PLP#2 occur simultaneously at another date-time. That is, each signal can coexist at the same point with respect to the time or frequency domain within the frame configuration.
Figure 76 illustrates an exemplary configuration of a transmission device (for example,
<img file="MX385274B_D0344.tif" />
336
IMPI
MEXICAN INSTITUTE OF PROPERTY OR INDUSTRIAL (MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY) a broadcasting station) that applies a transmission scheme in which a phase change is performed on the pre-encoded signals (or the pre-encoded signals that have changed base bands) in accordance with the DVB-T2 standard.
A PLP signal generator 7602 takes the PLP transmission data 7601 (data for the PLPs) and a control signal 7609 as input, performs error correction coding according to the error correction code information for the included PLPs. into the control signal 7609 and correlates according to the modulation scheme similarly included in the control signal 7609 and then outputs the baseband (quadrature) signal PLP 7603.
A P2 symbol signal generator 76 05 takes P2 symbol transmission data 7604 and control signal 76 09 as input, performs error correction coding according to the error correction code information for P2 symbol included in control signal 7609 and correlates according to the modulation scheme similarly included in control signal 7609 and then outputs baseband (quadrature) signal P2 7606.
A control signal generator 7 8 08 takes the P1 symbol transmit data 7607 and the P2 symbol transmit data 7604 as input and outputs the control signal 7609 for the group of symbols in Fig. P1 signaling data (7401), L1 presignaling data (7402),
<img file="MX385274B_D0345.tif" />
337
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY post-signalling data L1 (7403), the common PLP (7404), and PLPs #1 to #N (7405_l to 7405_N)). The 7609 control signal is composed of transmission scheme information (such as error correction codes and error correction rate, modulation scheme, block length, frame configuration, selected stream in which the precoding matrix, pilot symbol insertion scheme, IFFT/FFT information, the PAPR reduction scheme and the guard interval insertion scheme) for the group of symbols.
A framer 7610 takes a PLP baseband signal 7612, the P2 symbol baseband signal 7606, and the control signal 7609 as input, performs reordering with respect to time and frequency domains according to the information included in the control signal and therefore outputs the baseband (quad) signal 7611_1 for stream 1 (a correlated signal, i.e., a baseband signal using the modulation scheme) and the baseband (quadrature) signal 7611_2 for stream 2 (also a correlated signal, i.e. a baseband signal using the modulation scheme).
A signal processor 7612 takes the baseband signal for stream 1 7611_1, the baseband signal for stream 2 7611_2, and the control signal 7609 as input and then outputs modulated signals 1 (7613__l) and 2 (7613_2 ) ,
<img file="MX385274B_D0346.tif" />
338
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY that were processed in accordance with the transmission scheme included in control signal 7609.
Here, the characteristic feature is that when the transmission scheme is selected to perform the phase shift on the pre-encoded signals (or the pre-encoded signals having shifted basebands), the signal processor performs the phase shift on the pre-encoded signals (or the pre-encoded signals that have shifted basebands) as indicated in figures 6, 25 to 29 and 69. Signals 10 thus processed are output as Modulated Processed Signal 1 (7613 1) and Modulated Processed Signal 2 (7613 2).
A pilot inserter 7614_1 takes the processed modulated signal 1 (7613_1) and control signal 7609 as input, inserts the pilot symbols into the processed modulated signal 1 (7613 1) according to the embedding scheme of the included pilot symbol information into the control signal 7609, and outputs the modulated post-pilot symbol insertion signal 7615 1.
Another pilot inserter 7614_2 takes the processed modulated signal 2 (7613_2) and control signal 7609 as input, inserts the pilot symbols into the processed modulated signal 2 (7613_2) according to the pilot symbol information insertion scheme included in the control signal 7609, and outputs the modulated post-pilot symbol insertion signal 7615 2.
A 7616_1 IFFT unit takes the -5 modulated post-pilot symbol insertion signal 7615^1 and the control signal 7609
<img file="MX385274B_D0347.tif" />
IMPI
MEXICAN INSTITUTE OF PROPERTY OR INDUSTRIAL as input, applies an IFFT according to the IFFT method information included in control signal 7609, and outputs post-IFFT signal 7616_1.
Another 7616_2 IFFT unit takes the 7615_2 post-pilot symbol insertion modulated signal and the 7609 control signal as input, applies an IFFT according to the IFFT method information included in the 7609 control signal, and outputs the signal post-IFFT 7617_2.
The 7618_1 PAPR reducer takes the 7617_1 post-IFFT signal and the 7609 control signal as input, applies PAPR reduction processing to the 7617_1 post-IFFT signal according to the PAPR reduction information included in the 7609 control signal, and outputs the post-PAPR reduction signal 7619_1.
The 7618_2 PAPR reducer takes the 7617_2 post-IFFT signal and the 7609 control signal as input, applies PAPR reduction processing to the 7617_2 post-IFFT signal according to the PAPR reduction information included in the 7609 control signal, and outputs the post-PAPR reduction signal 7619_2.
The 7620_l guard interval inserter takes the 7619_1 post-PAPR reduction signal and the 7609 control signal as input, inserts the guard intervals into the 7619_1 post-PAPR reduction signal according to the interval insertion scheme information included in control signal 7609, and outputs post-safety interval insert signal 7621_1.
<img file="MX385274B_D0348.tif" />
340
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
The 7620_2 guard interval inserter takes the 7619_2 post-PAPR reduction signal and the 7609 control signal as input, inserts the guard intervals into the 7619_2 post-PAPR reduction signal according to the interval insertion scheme information included in control signal 7609, and outputs post-safety interval insert signal 7621_2.
A P1 symbol inserter 7622 takes the P1 symbol transmit data 7607 and the post-safety interval insert signals 7621_1 and 7621_2 as input, generates the P1 symbol signals from the P1 symbol transmit data 7607, adds the P1 symbols to the respective post-security interval insert signals 7621_1 and 7621_2, and outputs the post-Pl symbol add signals 7623_1 and 7623_2 . The P1 symbol signals can be added to one or both of the post-safety interval insertion signals 7621_1 and 7621_2. In the first case, the signal to which nothing is added has zero signals as the baseband signal in the interval that the symbols are added to the other signal.
The wireless processor 7624_1 takes the post-Pl symbol addition signal 7623_1 as input, performs processing such as frequency conversion and amplification thereon, and outputs the transmission signal 7625_1. So the transmission signal 7625_1 goes out as radio waves through the antenna 7626 1.
<img file="MX385274B_D0349.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
The wireless processor 7624_2 inputs the post-Pl symbol addition signal 7623_2 as input, performs processing such as frequency conversion and amplification thereof, and outputs the transmission signal 7625_2. Then the transmission signal 7625_2 is output as radio waves through the antenna 7626_2.
Figure 77 illustrates an exemplary time-frequency domain frame configuration where multiple PLPs are transmitted after symbol Pl, symbol P2, and the common PLP are transmitted. As shown, with respect to the frequency domain, stream 1 (a correlated signal, i.e. a baseband signal in which the modulation scheme has been used) uses subcarriers #1 to #M, as does stream 2 (also a correlated signal, ie a baseband signal in which the modulation scheme has been used). Therefore, when both si and s2 have a symbol on the same subcarrier at the same date-time, one symbol from each of the two streams is present at a single frequency. As explained in other embodiments, when using a transmission scheme that involves performing a phase shift on the pre-encoded signals (or pre-encoded signals having shifted basebands), the phase shift can be performed in addition to weighting using the precoding matrix (and, if applicable, after changing the baseband signal). Consequently, the signals zl and z2 are obtained. Each of the
<img file="MX385274B_D0350.tif" />
342
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY signals zl and z2 come out through a different antenna.
As shown in Fig. 77, slot 1 is used to transmit symbol group 7701 of PLP#1 using stream si and stream s2. Data is transmitted using a spatial multiplexing MIMO system as illustrated in Figure 23, or using a MIMO system with a fixed precoding matrix (where no phase shift is performed).
Slot 2 is used to transmit symbol group 7702 of PLP#2 using stream si. The data is 10 transmitted using a modulated signal.
Slot 3 is used to transmit symbol group 7703 using stream si and stream s2. The data is transmitted using a transmission scheme in which the phase shift is performed on the pre-encoded signals (or the pre-encoded signals having shifted base bands).
Slot 4 is used to transmit symbol group 7704 using stream si and stream s2 . Data is transmitted using the -0 space -1 time block codes that are described in Non-Patent Literature 9, 16, and 17.
When a broadcast station transmits the PLPs, as illustrated in Figure 77, the receiving device that receives the transmit signals needs to know the transmission pattern of each PLP. By
<img file="MX385274B_D0351.tif" />
343
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY Consequently, as described above, the post-signalling data L1 (7403 of FIG. 74), which is the symbol P2, must transmit the transmission pattern for each PLP. The following describes an example of a configuration scheme for symbols P1 and P2 in such circumstances.
Table 2 lists specific examples of the control information that is transmitted using the P1 symbol.
Table 2
<td>YES (3-bit)</td><td>control information</td>
<td> 000</td><td>T2_SISO (transmission of a signal modulated in the DVB-T2 standard)</td>
<td> 001</td><td>T2_MISO (transmission using block codes space-time in the DVB-T2 standard)</td>
<td> 010</td><td>NOT_T2 (using a different standard than DVB-T2)</td>
In the DVB-T2 standard, the SI control information (three data bits) is used by the receiving device to determine whether or not to use DVB-T2 and if so, to determine the DVB-T2 scheme.
<img file="MX385274B_D0352.tif" />
344
As indicated in Table 2 above the 3-bit SI data is set to 000 to indicate that the transmitted modulated signals conform to the transmission of a modulated signal in the DVB-T2 standard.
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY transmission.
Alternatively, the 3-bit SI data is set to 001 to indicate that the transmitted modulated signals conform to the use of space-time block codes in the DVB-T2 standard.
In DVB-T2, 010 to 111 are reserved for future use. In order to apply the present invention while maintaining compatibility with DVB-T2, the 3-bit SI data must be set to 010, for example (anything other than 000 and 001 can be used) and must indicate that a different standard than DVB-T2 is being used for the modulated signals. Thus, the receiving device or terminal has the ability to determine that the broadcasting station is transmitting using modulated signals that conform to a different standard than DVB-T2 by detecting that the data read is 010.
The following describes an example of a configuration scheme for a P2 symbol that is used when the modulated signals transmitted by the broadcasting station conform to a different standard than DVB-T2.
<img file="MX385274B_D0353.tif" />
345
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
In the first example, a scheme that uses the P2 symbol within the DVB-T2 standard.
Table 3 lists a first example of the control information carried by post-signaling data L1 in symbol P2.
Table 3
<td>PLP_MODE (2-bit)</td><td>control information</td>
<td> 00</td><td>SISO/MIMO</td>
<td> 01</td><td>MISO/MIMO (space-time block codes)</td>
<td> 10</td><td>MIMO (perform a phase shift on pre-encoded signals (or pre-encoded signals that have shifted basebands))</td>
<td> 11</td><td>MIME (using a fixed precoding matrix, or using spatial multiplexing)</td>
The following abbreviations are used in the tables above.
SISO: one input - one output (a modulated signal transmitted and received by an antenna).
SIMO: one input - multiple outputs (one modulated signal transmitted and received by multiple antennas).
MISO: multiple inputs - one output (multiple
<img file="MX385274B_D0354.tif" />
346
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY modulated signals transmitted and received by a single antenna).
MIMO: multiple inputs - multiple outputs (multiple modulated signals transmitted and received by multiple antennas).
The two-bit data listed in Table 3 is the PLP_MODE information. As shown in Fig. 77, this information is the control information to inform the terminal of the transmission scheme (symbol group of PLP#1 to #4 in Fig. 77; hereinafter, symbol group) . The PLP_MODE information is present in each PLP. That is, in Fig. 77, the PLP_MODE information for PLP.#1, for PLP#2, for PLP#3, for PLP#4, and so on, is transmitted by the broadcast station. Naturally, the terminal recognizes the transmission scheme used by the broadcasting station for the PLPs by demodulating this information (or by performing error correction decoding on the same).
When the PLP_MODE is set to 00, data is transmitted by that PLP using a scheme where a single modulated signal is transmitted. When PLP_MODE is set to 01, data is transmitted by that PLP using a scheme in which multiple modulated signals are transmitted using space-time block codes. When the PLP_MODE is set to 10, data is transmitted by that PLP using a scheme where a phase shift is performed on the pre-encoded (or pre-encoded and changed) signals. When the PLP_MODE is set
<img file="MX385274B_D0355.tif" />
347
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY at 11, the data is transmitted by that PLP using a scheme in which a fixed precoding matrix is used in which a spatial multiplexing MIMO system is used.
When the PLP_MODE is set to anything between 01 and 11, the broadcast station should preferably transmit specific processing (for example, the specific transmission scheme by which phase shift is applied to pre-encoded signals (or pre-encoded signals that have changed basebands), the encoding scheme of the space-time block codes, or the configuration of the precoding matrix) to the terminal. The following describes an alternative to Table 3, such as a configuration scheme for control information that includes the control information that is needed in such circumstances.
Table 4 lists a second example of control information carried by post-signalling data L1 in symbol P2, different from that in Table 3.
Table 4
<td>Name</td><td>No. of bits</td><td>control information</td>
<td rowspan="2">PLP_mDE (1- J-bit</td><td>Q</td><td>SISO/SISO</td>
<td> 1</td><td>using one of (1) timespace block codes; (11) phase shifting that is performed on pre-encoded signals (or pre-encoded signals having shifted base bands); (iii) a fixed, precoding matrix; and {iv) spatial multiplexing</td>
<img file="MX385274B_D0356.tif" />
348
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
<td rowspan="2">MIMOJlOfE (1- bit)</td><td> 0</td><td>phase shift on pre-encoded signals (or pre-encoded signals that have shifted basebands) is OFF</td>
<td> 1</td><td>phase shift on precoded signals (or precoded signals that have shifted basebands) is ON</td>
<td rowspan="4">M1MO_PATTESN#1 (2-bit)</td><td> 00</td><td>space-time block codes</td>
<td> 01</td><td>fiia precoding matrix #1</td>
<td> 10</td><td>fixed precoding matrix #two</td>
<td> 11</td><td>spatial multiplexing</td>
<td rowspan="4">MIMO_PATTESH#2 (2-bit)</td><td> 00</td><td>phase shift in pre-encoded signals (or pre-encoded signals that have shifted basebands), version #1</td>
<td> 01</td><td>phase shift in precoded signals (or precoded signals that have shifted basebands), version #2</td>
<td> 10</td><td>phase shift in precoded signals (or precoded signals that have shifted basebands), version #3</td>
<td> 11</td><td>phase shift in precoded signals (or precoded signals that have shifted basebands), version #4</td>
As indicated in Table 4, four types of control information are possible: 1-bit PLP_MODE information, 1-bit MIMO_MODE information, 2-bit MIMO_PATTERN#1 information, and 2-bit MIMO_PATTERN#2 information. As shown in Fig. 77, the terminal is notified of the transmission scheme for each PLP (namely PLP#1 to #4) by this information. All four types of control information are present in each PLP. That is, in Fig. 77, the PLP_MODE information, the information
<img file="MX385274B_D0357.tif" />
349
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
MIMO_MODE, MIMO_PATTERN#1 information, and MIM0_PATTERN#2 information for PLP#1, for PLP#2, for PLP#3, for PLP#4, and so on, is transmitted by the broadcast station. Naturally, the terminal recognizes the transmission scheme used by the broadcasting station for the PLPs by demodulating this information (or by performing error correction decoding on the same).
When the PLP__MODE is set to 0, data is transmitted by that PLP using a scheme in which a single modulated signal is transmitted. When the PLP_MODE is set to 1, data is transmitted by that PLP using a scheme in which any one of the following applies: (i) space-time block codes are used; (ii) a MIMO system is used where a phase shift is performed on the pre-encoded signals (or the pre-encoded signals having shifted basebands); (iii) a MIMO system is used where a fixed precoding matrix is used; and (iv) spatial multiplexing is used.
When the PLP_MODE is set to 1, the MIMO_MODE information is valid. When the MIMO_MODE information is set to 0, the data is transmitted without a phase shift performed on the pre-encoded signals (or the pre-encoded signals having shifted base bands). When the MIMO MODE information is set to 1, data is transmitted using a phase shift that is performed on the pre-encoded signals (or the pre-encoded signals that have shifted base bands).
<img file="MX385274B_D0358.tif" />
350
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
When the PLP_MODE is set to 1 and the MIMO_MODE information is set to 0, the MIMO_PATTERN#1 information is valid. When the MIMO_PATTERN#1 information is set to 00, data is transmitted using space-time block codes. When the MIMO_PATTERN#1 information is set to 01, the data is transmitted using the fixed precoding matrix #1 for weighting. When the MIMO_PATTERN#1 information is set to 10, the data is transmitted using the fixed precoding matrix #2 for weighting. (Precoding matrix #1 and precoding matrix #2 are different matrices.) When the MIMO_PATTERN#1 information is set to 11, the data is transmitted using spatial multiplexing.
When the PLP_MODE is set to 1 and the MIMO_MODE information is set to 1, the MIMO_PATTERN#2 information is valid. When the MIMO_PATTERN#2 information is set to 00, data is transmitted using version #1 of a phase shift in the pre-encoded signals (or pre-encoded signals that have shifted base bands). When the MIMO_PATTERN#2 information is set to 01, data is transmitted using version #2 of a phase shift in the pre-encoded signals (or pre-encoded signals that have changed base bands). When the MIMO_PATTERN#2 information is set to 10, data is transmitted using version #3 of a phase shift in the precoded signals (or the precoded signals that have shifted basebands) when the
<img file="MX385274B_D0359.tif" />
351
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY information MIMO_PATTERN#2 is set to 11, data is transmitted using version #4 of a phase shift in the pre-encoded signals (or pre-encoded signals that have changed base bands). Although the phase change is done in four different versions #1 to 4, the following three approaches are possible, giving two different schemes #A and #B:
Phase changes made using scheme #A and made using scheme #B include identical and different changes;
A phase change value included in scheme #A is not included in scheme #B; Y
Multiple phase changes used in scheme #A are not included in scheme #B.
The control information listed in Table 3 and Table 4, above, is carried by post-signaling data L1 in symbol P2. However, in the DVB-T2 standard, the amount of information that is transmitted as a P2 symbol is limited. Therefore, the information listed in Tables 3 and 4 is added to the information transmitted by the P2 symbol in the DVB-T2 standard. When this leads to exceeding the limit of the information being transmitted as the P2 symbol, then, as shown in Fig. 78, a PLP signaling (7801) can be prepared in order to transmit the necessary control information (at least partially, i.e. L1 post-signaling data and PLP signaling are transmitted) not included
<img file="MX385274B_D0360.tif" />
352
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY in the DVB-T2 specification. While Figure 78 illustrates a frame configuration identical to that of Figure 74, no limitation in this regard is intended. A specific time and specific carrier region can also be assigned in the time-frequency domain for PLP signaling, as in Fig. 75. That is, PLP signaling can be freely assigned in the time-frequency domain.
As described above, selecting a transmission scheme that uses a multi-carrier scheme such as OFDM and preserves compatibility with the DVB-T2 standard, and in which the phase shift is performed on the pre-encoded signals (or the signals precoded having shifted basebands) has the merit of achieving better reception quality in the LOS environment and higher transmission speeds. While the present invention describes possible transmission schemes for carriers that are a spatial multiplexing MIMO, a MIMO using a fixed precoding matrix, a transmission scheme that performs a phase shift on the precoded signals (or on the precoded and changed), space-time block codes, and transmission schemes that transmit only the current if, whereby no limitation is intended in this way.
Also, although the description indicates that the broadcasting station selects one of the transmission schemes mentioned above, not all of these transmission schemes have to be selected.
<img file="MX385274B_D0361.tif" />
353
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY be available in the selection. Other option sets include:
MIMO that uses a fixed precoding matrix, a transmission scheme that performs a phase shift on the precoded signals (or on the precoded and shifted ones), space-time block codes, and transmission schemes transmitting only the si stream;
MIMO which uses a fixed precoding matrix, a transmission scheme that performs a phase shift on the precoded (or precoded and shifted) signals and space-time block codes;
MIMO that uses a fixed precoding matrix, a transmission scheme that performs a phase shift on the precoded signals (or both precoded and shifted), and transmission schemes transmitting only the si stream;
A transmission scheme that performs a phase shift on the precoded (or precoded and changed) signals, space-time block codes, and transmission schemes transmitting only the si current;
MIMO that uses a fixed precoding matrix and a transmission scheme that performs a phase shift on the precoded (or precoded and shifted) signals;
A transmission scheme that performs a phase shift on the precoded (or precoded and changed) signals and space-time block codes;
<img file="MX385274B_D0362.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
354
A transmission scheme that performs a phase shift on the pre-encoded signals (or both pre-encoded and changed) and transmission schemes transmitting only the si current.
As such, including a transmission scheme that performs a phase shift on the pre-encoded (or pre-encoded and shifted) signals, achieves the advantage of leading to higher transmission speeds in the LOS environment and better reception quality for the device. of reception.
Here, since SI needs to be set for the Pl symbol as described above, another configuration scheme for the control information (with respect to the transmission scheme for each PLP) different from that in Table 3 is possible. For example, see Table 5, below.
Table 5
<td>PLP_MODE (2-bit)</td><td>control information</td>
<td> 00</td><td>SISO/MIMO</td>
<td> 01</td><td>MISO/MIMO (space-time block codes)</td>
<td> 10</td><td>MIME (phase shift in precoded signals (or precoded signals that have shifted basebands))</td>
<td> 11</td><td>Reserved</td>
<img file="MX385274B_D0363.tif" />
355
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Table 5 differs from Table 3 in that setting the PLP_MODE information to 11 is reserved. As such, when the transmission scheme for the PLPs is as described in one of the previous examples, the number of bits that make up the information PLP_MODE as in the examples in Tables 3 and 5 can be higher or lower according to the transmission schemes available for selection.
Similarly, for Table 4, when for example, a MIMO scheme is used with a transmission scheme that does not support a phase shift of the precoded signals (or the precoded signals having shifted basebands), the control information MIMO_MODE is not required. Also, when for example MIMO schemes using a fixed precoding matrix are not supported, then the MIMO_PATTERN#1 is not needed. Also, when multiple precoding matrices are not needed, the 1-bit information can be used instead of the 2-bit information. Also, two or more bits can be used when multiple precoding matrices are available.
The same principles apply to the MIMO_PATTERN#2 information. When the transmission scheme does not require multiple schemes to perform a phase shift on the precoded signals (or the precoded signals having shifted basebands), the 1-bit information can be used instead of the 2-bit information. Also, two or more bits can be used when multiple phase shift schemes are available.
<img file="MX385274B_D0364.tif" />
356
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Furthermore, although the present embodiment describes a transmission device having two antennas, no limitation in this regard is intended. Control information can also be transmitted in the same way using more than two antennas. In such circumstances, the number of bits in each type of control information can be increased as required in order to perform transmission using four antennas. The above description of the transmission of control information in symbol P1 and symbol P2 also applies in such cases.
While Figure 77 illustrates the frame configuration for groups of PLP symbols transmitted by the broadcast station that are divided with respect to the time domain, the following variation is also possible.
Unlike Fig. 77, Fig. 79 illustrates an example of a scheme for arranging symbol streams si and stream 2 in the time-frequency domain, after symbol Pl, symbol P2 and common PLP are transmitted. In Fig. 79, the symbols labeled #1 are symbols from the PLP#1 symbol group of Fig. 77 . Similarly, symbols labeled #2 are symbols from the PLP#2 symbol group, symbols labeled #3 are symbols from the PLP#3 symbol group, and symbols labeled #4 are symbols from the PLP#3 symbol group. PLP#4, all from Figure 77. As in Figure 77, PLP#1 is used to transmit data using a MIMO system of
<img file="MX385274B_D0365.tif" />
357
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY spatial multiplexing as illustrated in Figure 23, or using a MIMO system with a fixed precoding matrix. PLP#2 is used to transmit data using only a modulated signal. PLP#3 is used to transmit data using a transmission scheme in which a phase shift is performed on the pre-encoded signals (or the pre-encoded signals having shifted base bands). PLP#4 is used to transmit data using space-time block codes.
In Figure 79, when both si and s2 have a symbol on the same subcarrier (given as carrier in Figure 79) at the same date-time, one symbol from each of the two streams is present on the common frequency. As explained in other embodiments, when using a transmission scheme involving the mode of a phase shift in the pre-encoded signals (or the pre-encoded signals having shifted basebands), the phase shift may be performed in addition to the weighting using the precoding matrix (and if applicable after changing the baseband signal). Consequently, the signals zl and z2 are obtained. Each of the signals zl and z2 goes out through a different antenna.
As described above, Figure 79 differs from Figure 77 in that the PLPs are partitioned with respect to the time domain. In addition, Figure 79 has multiple PLPs divided with respect to the time and frequency domains. That is, for example, the symbols of PLP#1 and PLP#2 are in
<img file="MX385274B_D0366.tif" />
358
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY date-time 1, while PLP#3 and PLP#4 symbols are at date-time 3. As such, PLP symbols that have a different index (#X, where X = 1, 2 and so on) can be assigned to each symbol (composed of a datetime and a subcarrier).
Although for the sake of simplicity Figure 79 lists only #1 and #2 in date-time 1, no limitation in this regard is intended. Indices of the PLP symbols, other than #1 and #2, may be in date-time #1. Furthermore, the relationship between the PLP indices and the subcarriers at date-time 1 is not limited to what is illustrated in Fig. 79. The indices of any PLP symbols can be assigned to any subcarrier. The same applies to other date-times, where the indices of any PLP symbols can be assigned to them.
Unlike Fig. 77, Fig. 80 illustrates an example of a scheme for arranging symbol streams si and stream 2 in the time-frequency domain, after symbol Pl, symbol P2 and common PLP are transmitted. The characteristic feature of Figure 80 is that, assuming the use of multiple antennas for transmission is the basis of the PLP transmission scheme, then transmission using only stream 1 is not an option for frame T2.
Therefore, in Figure 80, symbol group 8001 of PLP#1 transmits data using a system
<img file="MX385274B_D0367.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
359
Spatial multiplexing MIMO or a MIMO system using a fixed precoding matrix. Also, PLP#2 symbol group 8002 transmits the data using a transmission scheme that performs a phase shift on the precoded (or precoded and changed) signals. In addition, symbol group 8003 of PLP#3 transmits the data using space-time block codes. The PLP symbol group following the 8003 symbol group of PLP#3 transmits the data using one of these schemes, namely, using a spatial multiplexing MIMO system or a MIMO system using a fixed precoding matrix, using a transmission that performs a phase shift on the precoded (or precoded and changed) signals or using space-time block codes.
Unlike Fig. 79, Fig. 81 illustrates an example of a scheme for arranging symbol streams si and stream 2 in the time-frequency domain, after symbol Pl, symbol P2 and common PLP are transmitted. In Figure 81, the symbols labeled #1 are symbols from the PLP#1 symbol group of Figure 80. Similarly, symbols labeled #2 are symbols from the PLP#2 symbol group, symbols labeled #3 are symbols from the PLP#3 symbol group, and symbols labeled #4 are symbols from the PLP#3 symbol group. PLP#4, all from figure 80. As in figure 80, PLP#1 is used to transmit the data using a spatial multiplexing MIMO system as illustrated in figure 23 or using
<img file="MX385274B_D0368.tif" />
360
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY a MIMO system with a fixed precoding matrix. PLP#2 is used to transmit the data using a transmission scheme in which a phase shift is performed on the pre-encoded signals (or the pre-encoded signals having shifted base bands). PLP#3 is used to transmit the data using the space-time block codes.
In figure 81, when both si and s2 have a symbol on the same subcarrier (given as carrier in figure 81) at the same date-time, one symbol from each of the two currents is present on the common frequency . As explained in other embodiments, when using a transmission scheme that involves the mode of a phase shift in the pre-encoded signals (or the pre-encoded signals having shifted basebands), the phase shift may be performed in addition to the weighting using the precoding matrix (and if applicable after changing the baseband signal). Consequently, the signals zl and z2 are obtained. Each of the signals zl and z2 goes out through a different antenna.
Figure 81 differs from Figure 80 in that the PLPs are partitioned with respect to the time and frequency domain. That is, for example, PLP#1 and PLP#2 symbols are both at date-time 1. As such, PLP symbols that have a different index (#X, where X = 1, 2 and so on) can be assigned to each symbol (composed of a datetime and a subcarrier).
<img file="MX385274B_D0369.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
361
Although for the sake of simplicity, FIG. 81 lists only #1 and #2 in date-time 1, no limitation in this regard is intended. Indices of the PLP symbols, other than #1 and #2, may be in date-time #1. Also, the relationship between the PLP indices and the subcarriers at date-time 1 is not limited to what is illustrated in Fig. 81. The indices of any PLP symbols can be assigned to any subcarrier. The same applies to other date-times, where the indices of any PLP symbols can be assigned to them. On the other hand, a date-time can also have symbols from only one PLP assigned to it, as is the case for date-time 3. In other words, any assignment of the PLP symbols in the time-frequency domain is allowed. .
Thus, since the T2 frame does not include the PLPs that use transmission schemes that only transmit the si stream, the dynamic range of the signals received by the terminal can be restricted, which probably leads to improving the quality of the received signal.
Although Fig. 81 is described using examples where one is selected to transmit the data using a spatial multiplexing MIMO system or a MIMO system using a fixed precoding matrix, transmission data using a transmission scheme that performs a change of phase in precoded (or precoded and changed) signals and transmission data using space-time block codes, the
<img file="MX385274B_D0370.tif" />
362
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY selection of the transmission scheme is not limited to these. Other possibilities include:
select one to transmit data that uses a transmission scheme that performs a phase shift on the precoded (or precoded and changed) signals, transmit data using space-time block codes, and transmit data using a MIMO system that uses a matrix fixed precoding;
select one to transmit data that uses a transmission scheme that performs a phase shift on the precoded signals (or both precoded and changed) and transmit data using space-time block codes; and selecting one to transmit data using a transmission scheme that performs a phase shift on the precoded signals (or both precoded and changed) and transmitting data using a MIMO system using a fixed precoding matrix.
While the explanation above is given for a T2 frame having multiple PLPs, the following describes a T2 frame having only one PLP.
Figure 82 illustrates an exemplary frame configuration for streams si and stream s2 in the time-frequency domain where frame T2 has only one PLP. Although Fig. 82 indicates control symbols, these are equivalent to the symbols described above, such as the symbols "P1" and "P2". In figure 82, slot 1 is used to transmit a
<img file="MX385274B_D0371.tif" />
363
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY first T2 frame, slot 2 is used to transmit a second T2 frame, slot 3 is used to transmit a third T2 frame, and slot 4 is used to transmit a fourth T2 frame.
Also, the first frame T2 in Fig. 82 carries symbol group 8101 of PLP#1-1. The selected transmission scheme is spatial multiplexing MIMO or MIMO using a fixed precoding matrix.
The second frame T2 transmits symbol group 8102 of PLP#2-1. The transmission scheme is a transmission using a single modulated signal.
The third frame T2 transmits symbol group 8103 of PLP#3-1. The transmission scheme is transmission that performs a phase shift on the pre-encoded (or pre-encoded and shifted) signals.
The fourth frame T2 carries symbol group 8104 from PLP#4-1. The transmission scheme is the transmission using the space-time block codes.
In Fig. 82, when both si and s2 have a symbol on the same subcarrier at the same date-time, one symbol from each of the two streams is present on the common frequency. As explained in other embodiments, when using a transmission scheme involving the mode of a phase shift in the pre-encoded signals (or the pre-encoded signals having shifted base bands), the phase shift may be performed in addition to the weighting using the precoding matrix (and if it is
<img file="MX385274B_D0372.tif" />
364
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY applicable after changing the baseband signal). Consequently, the signals zl and z2 are obtained. Each of the signals zl and z2 goes out through a different antenna.
As such, the transmission scheme can be established by taking the transmit data rate and the receive data rate of the terminal into consideration for each PLP. This has the dual merit of allowing data transmission speed to be improved and ensuring high data reception quality. The configuration scheme for the control information related to the transmission scheme and so on for the Pl and P2 symbols (and the PLP signaling, if applicable) can be as presented in Tables 2 to 5, thus obtaining the same effects. Figure 82 differs from Figure 7 in that, while the frame configuration of Figure 77 and the like include multiple PLPs in a single T2 frame, thus requiring control information related to transmission scheme and so on from each PLP, the frame configuration of FIG. 82 includes a single PLP per T2 frame. As such, the only control information needed is for transmission information and so forth related to a PLP.
Although the description above describes the schemes for transmitting the information related to the PLP transmission scheme using the symbols Pl and P2 (and the PLP signaling, if applicable), the following describes a
<img file="MX385274B_D0373.tif" />
365
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY Scheme to transmit the information related to the PLP transmission scheme without using the P2 symbol.
Figure 83 illustrates a frame configuration in the time-frequency domain applicable when a terminal receives data transmitted by a broadcasting station that is not compatible with the DVB-T2 standard. In Figure 83, components that operate in the manner described for Figure 74 use identical reference numerals. The frame of Fig. 83 includes P1 signaling data (7401), first signaling data (8301), second signaling data (8302), a common PLP (7404), and PLPs #1 to #N ( 7405_l to 7405_N). As such, the P1 signaling data (7401), the first signaling data (8301), the second signaling data (8302), the common PLP (7404), and the PLPs #1 to #N (7405_l to 7405_N) form a frame, thus constituting a frame unit.
Signaling data P1 (7401) is a symbol used for signal reception by the receiving device and for frequency synchronization (including frequency offset estimation). Furthermore, this data conveys the identification related to whether or not the frame conforms to the DVB-T2 standard, for example, using the SI data as indicated in Table 2 for this purpose.
The first signaling data (8301) is used to transmit the information related to the schemes used to transmit the frame, concerning the guard interval, the
<img file="MX385274B_D0374.tif" />
366
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY information on the signal processing scheme used to reduce the PAPR, the modulation scheme used to transmit the post-signaling Ll data, the FEC scheme, its coding rate, length and size of the Ll post-signaling data, they payload pattern, specific cell numbers (frequency region) and depending on whether a normal mode or an extended mode is in use and other such information. Here, the first signaling data (8301) need not necessarily be data conforming to the DVB-T2 standard.
The second signaling data (83 02) is used to transmit such information as the number of PLPs, the frequency region in use, the specific numbers of PLPs, the modulation scheme used to transmit the PLPs, the FEC scheme, the rate encoding thereof, the number of blocks transmitted by each PLP and so on.
The frame configuration of Figure 83 illustrates the first signaling data (8301), the second signaling data (8302), the Ll post-signaling data (7403), the common PLP (7404), and PLPs #1 to #N (7405_l to 7405_N) divided with respect to the time domain for transmission. However, two or more of these signals can occur simultaneously. Figure 84 illustrates one such case. As shown in figure 84, the first signaling data, the second signaling data and the common PLP share a common date-time
<img file="MX385274B_D0375.tif" />
367
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY while PLP#1 and PLP#2 share a different common date-time. That is, each signal can coexist at the same point with respect to the time or frequency domain within the frame configuration.
Figure 85 illustrates an exemplary configuration of a transmission device (for example, a broadcast station) that applies a transmission scheme in which a phase shift is performed on pre-encoded signals (or pre-encoded signals having shifted basebands). ) as explained so far but conforming to a different standard than the DVB-T2 standard. In Figure 85, components that operate in the manner described for Figure 75 use identical reference numerals and refer to the descriptions above.
A control signal generator 76 08 takes the first and second signaling data 8501 and the PI symbol transmission data 7607 as input and outputs the control signal 7609 (composed of such information as error correction codes and the coding rate thereof, the modulation scheme, the block length, the frame configuration, the selected transmission scheme in which the precoding matrix is changed regularly, the pilot symbol insertion scheme, the IFFT/FFT information, the PAPR reduction method, and the guard interval insertion scheme) for the transmission scheme of each group of symbols in Figure 83.
<img file="MX385274B_D0376.tif" />
368
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
A control symbol signal generator 8502 takes the first and second transmission data of signaling data 8501 and control signal 7609 as input, performs error correction coding in accordance with the error correction code information for the first and second signaling data included in the control signal 7609 and performs correlation in accordance with the modulation scheme that is similarly included into control signal 7609 and then outputs first and second signaling data baseband (quadrature) signals 8503.
In FIG. 85, the framer 7610 takes the baseband signal 8503 generated by the control symbol generator 8502 as input, rather than the baseband signal 7606 generated by the P2 symbol generator 7605 of figure 76.
The following describes, with reference to Figure 77, a transmission scheme for the control information (information transmitted by the P1 symbol and by the first and second signaling data) and by the transmission signal framing for a broadcast station (base station) applying a transmission scheme transmission in which a phase shift is performed on the pre-scrambled (or pre-scrambled and shifted) signals in a system that does not conform to the DVB-T2 standard.
Figure 77 illustrates a frame configuration
<img file="MX385274B_D0377.tif" />
369
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY example in the time-frequency domain where multiple PLPs are transmitted after the first and second signaling data and the common PLP are transmitted. In Fig. 77, the current si uses subcarrier #1 through subcarrier #M in the frequency domain. Similarly, current s2 also uses subcarrier #1 through subcarrier #M in the frequency domain. Therefore, when both si and s2 have a symbol on the same subcarrier at the same date-time, one symbol from each of the two streams is present at a single frequency. As explained in other embodiments, when using a transmission scheme that involves performing a phase shift on the precoded signals (or precoded signals that have shifted basebands), the phase shift can be performed in addition to weighting using the precoding matrix (and if applicable after changing the baseband signal). Consequently, the signals zl and z2 are obtained. A different antenna outputs each of the signals zl and z2.
As shown in Fig. 77, slot 1 is used to transmit symbol group 7701 of PLP#1 using stream si and stream s2. Data is transmitted using a spatial multiplexing MIMO system as illustrated in Fig. 23 or using a MIMO system with a fixed precoding matrix.
Slot 2 is used to transmit the group of
<img file="MX385274B_D0378.tif" />
370
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY symbols 7702 of PLP#2 using the current si. Data is transmitted using a modulated signal.
Slot 3 is used to transmit symbol group 7703 of PLP#3 using streams si and stream s2 . Data is transmitted using a transmission scheme where a phase shift is performed on the pre-encoded signals (or pre-encoded signals with shifted base bands).
Slot 4 is used to transmit symbol group 7704 of PLP#4 using streams si and stream s2. The data is transmitted using the space-time block codes.
When a broadcast station transmits the PLPs as illustrated in Fig. 77, the receiving device in Fig. 64 that receives the transmit signals needs to know the transmission pattern of each PLP. Therefore, as described above, the first and second signaling data are used to transmit the transmission pattern for each PLP. The following describes an example of a configuration scheme for the symbol Pl and for the first and second signaling data in such circumstances. A specific example of the control information transmitted using the Pl symbol is given in Table 2.
In the DVB-T2 standard, the control information SI (three data bits) is used by the receiving device to determine whether or not DVB-T2 is being used and in the case
<img file="MX385274B_D0379.tif" />
371
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY yes, determine the transmission scheme. The 3-bit SI data is set to 000 to indicate that the modulated signals are being transmitted in accordance with the transmission of a modulated signal in the DVB-T2 standard.
Alternatively, the 3-bit SI data is set to 001 to indicate that the modulated signals are being transmitted in accordance with the use of space-time block codes in the DVB-T2 standard.
In DVB-T2, 010 to 111 are reserved for future use.
In order to apply the present invention while maintaining compatibility with DVB-T2, the 3-bit SI data must be set to 010, for example (anything other than 000 and 001 can be used) and must indicate that a different standard than DVB-T2 is being used for the modulated signals. Thus, the receiving device or terminal has the ability to determine that the broadcasting station is transmitting using the modulated signals that conform to a different standard than DVB-T2 by detecting that the data reads 010.
The following describes a configuration scheme for the first and second signaling data used when the modulated signals transmitted by the broadcasting station do not conform to the DVB-T2 standard. A first example of the control information for the first and second signaling data is given in Table 3.
The two-bit data listed in Table 3 is the
<img file="MX385274B_D0380.tif" />
372
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY information PLP_MODE. As shown in Fig. 77, this information is the control information for informing the terminal of the transmission scheme for each PLP (PLP#1 to #4 in Fig. 77). The PLP_MODE information is present in each PLP. That is, in Fig. 77, the PLP_MODE information for PLP#1, for PLP#2, for PLP#3, for PLP#4 and so on, is transmitted by the broadcast station. Naturally, the terminal recognizes the transmission scheme used by the broadcast station for the PLPs by demodulating (or performing error correction decoding) on this information.
When PLP_MODE is set to 0, data is transmitted by that PLP which uses a scheme where a single modulated signal is transmitted. When PLP_MODE is set to 01, data is transmitted by that PLP which uses a scheme in which multiple modulated signals are transmitted using space-time block codes. When the PLP_MODE is set to 10, data is transmitted by that PLP using a scheme in which a phase shift is performed on the pre-encoded signals (or pre-encoded signals having shifted base bands). When the PLP_MODE is set to 11, the data is transmitted by that PLP using a scheme in which a fixed precoding matrix is used or in which a spatial multiplexing MIMO system is used.
When the PLP_MODE is set to anything between 01 and 11, the broadcast station should preferably transmit the
<img file="MX385274B_D0381.tif" />
373
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY specific processing (for example, the specific transmission scheme by which a phase shift is applied to pre-encoded signals (or pre-encoded signals that have shifted basebands), the encoding scheme for transmission codes space-time block or precoding matrix configuration) to the terminal. The following describes an alternative to Table 3, such as a configuration scheme for the control information that includes the control information that such circumstances need.
A second example of the control information for the first and second signaling data is given in Table 4.
As indicated in Table 4, four types of the control information are possible: 1-bit PLP_MODE information, 1-bit MIMO_MODE information, 2-bit MIMO_PATTERN#1 information and 2-bit MIMO_PATTERN#2 information. As shown in Fig. 77, the terminal is notified of the transmission pattern for each PLP (namely, PLP#1 to #4) by this information. All four types of control information are present in each PLP. That is, in Fig. 77, the PLP_MODE information, the MIMO_MODE information, the MIMO_PATTERN#1 information and the MIMO_PATTERN#2 information for PLP#1, for PLP#2, for PLP#3, for PLP#4 and so on, are transmitted by the broadcasting station. Naturally, the terminal recognizes the transmission scheme used by the broadcast station for PLPs by demodulation (or
<img file="MX385274B_D0382.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
374 performing error-correcting decoding) on this information.'
When PLP_MODE is set to 0, data is transmitted by that PLP using a scheme where a single modulated signal is transmitted. When the PLP_MODE is set to 1, data is transmitted by that PLP using a scheme in which any one of the following applies: (i) space-time block codes are used; (ii) a MIMO system is used where a phase shift is performed on the pre-encoded signals (or the pre-encoded signals having shifted base bands); (iii) a MIMO system is used where a fixed precoding matrix is used and (iv) spatial multiplexing is used.
When the PLP_MODE is set to 1, the MIMO_MODE information is valid. When the MIMO_MODE information is set to 0, the data is transmitted without using a phase shift performed on the pre-encoded signals (or pre-encoded signals having shifted base bands). When the MIMO_MODE information is set to 1, the data is transmitted using a phase shift performed on the pre-encoded signals (or the pre-encoded signals having shifted base bands).
When the PLP_MODE information is set to 1 and the MIMO_MODE information is set to 0, the MIMO_PATTERN#1 information is valid. As such, when the MIMO_PATTERN#1 information is set to 00, data is transmitted
<img file="MX385274B_D0383.tif" />
375
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY using space-time block codes. When the MIMO_PATTERN#1 information is set to 01, the data is transmitted using the fixed precoding matrix #1 for weighting. When the MIMO_PATTERN#1 information is set to 10, the data is transmitted using the fixed precoding matrix #2 for weighting. (Precoding matrix #1 and precoding matrix #2 are different matrices.) When the MIMO_PATTERN#1 information is set to 11, data is transmitted using MIMO spatial multiplexing. When the PLP_MODE information is set to 1 and the MIMO_MODE information is set to 1, the MIMO_PATTERN#2 information is valid. When the MIMO_PATTERN#2 information is set to 00, data is transmitted using version #1 of a phase shift in the pre-encoded signals (or pre-encoded signals that have shifted base bands). When the MIMO_PATTERN#2 information is set to 01, data is transmitted using version #2 of a phase shift in the pre-encoded signals (or pre-encoded signals that have changed base bands). When the MIMO_PATTERN#3 information is set to 10, data is transmitted using version #3 of a phase shift in the pre-encoded signals (or pre-encoded signals that have shifted base bands). When the MIM0_PATTERN#4 information is set to 11, data is transmitted using version #4 of a phase shift in the precoded signals (or precoded signals that have
<img file="MX385274B_D0384.tif" />
376
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY changed base bands). Although the phase change is done in four different versions #1 to 4, the following three approaches are possible given two different schemes #A and #B:
The phase changes that are made using scheme 5 #A and those that are made using scheme #B include identical and different changes.
Some phase shift values are included in scheme #A but are not included in scheme #B; Y
Multiple phase shifts used in Scheme #A are not included in Scheme #B.
The control information listed in Table 3 and Table 4, above, is carried by the first and second signaling data. In such circumstances there is no particular need to use the PLPs to transmit the control information.
As described above, selecting a transmission scheme that uses a multi-carrier scheme, such as OFDM, while being identifiable as differing from the DVB-T2 standard and in which a phase shift is performed on the pre-encoded signals (or pre-encoded signals having shifted base bands), has the merit of bringing better reception quality in the LOS environment and higher transmission speeds. While the present invention describes possible transmission schemes for carriers that are a spatial multiplexing MIMO, a MIMO that uses a matrix of
<img file="MX385274B_D0385.tif" />
377
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY fixed precoding, a transmission scheme that performs a phase shift on the precoded signals (or on the precoded and changed ones), space-time block codes, and transmission schemes transmitting only the current if, where from this way no limitation is intended.
Also, although the description indicates that the broadcast station selects one of the aforementioned transmission schemes, these are not the only transmission schemes available for selection. Other options include: MIMO that uses a fixed precoding matrix, a transmission scheme that performs a phase shift on the precoded (or precoded and shifted) signals, space-time block codes, and transmission schemes transmitting only the current yes;
MIMO which uses a fixed precoding matrix, a transmission scheme that performs a phase shift on the precoded (or precoded and shifted) signals and space-time block codes;
MIMO that uses a fixed precoding matrix, a transmission scheme that performs a phase shift on the precoded signals (or both precoded and shifted), and transmission schemes transmitting only the si stream;
A transmission scheme that performs a phase shift on the precoded (or precoded and changed) signals, space-time block codes, and transmission schemes.
<img file="MX385274B_D0386.tif" />
378
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY transmission transmitting only the current yes;
MIMO that uses a fixed precoding matrix and a transmission scheme that performs a phase shift on the precoded (or precoded and shifted) signals;
A transmission scheme that performs a phase shift on the precoded (or precoded and changed) signals and space-time block codes; Y
A transmission scheme that performs a phase change on the precoded signals (or on the precoded and changed) and transmission schemes transmitting only the si current.
As such, including a transmission scheme that performs a phase shift on the precoded (or precoded and shifted) signals, achieves the advantage of leading to higher transmission speeds in the LOS environment and better reception quality for the receiving device.
Here, since as described above the SI data needs to be set for the Pl symbol, another configuration scheme is possible for the control information (with respect to the transmission scheme for each PLP) transmitted as the first and second transmission data. signaling different from those in Table 3. For example, see Table 5, above.
Table 5 differs from Table 3 in that setting the PLP_MODE information to 11 is reserved. As such, when the transmission scheme for the PLPs is as described in
<img file="MX385274B_D0387.tif" />
379
IMPI
MEXICAN INSTITUTE OF PROPERTY OR INDUSTRIAL one of the previous examples, the number of bits that make up the PLP_MODE information as in the examples in Tables 3 and 5 can be higher or lower according to the transmission schemes available for selection.
Similarly, for Table 4, when for example, a MIMO scheme is used with a transmission scheme that does not support phase shifting of the pre-encoded signals (or pre-encoded signals having shifted base bands), the control information MIMO_MODE is not required. Also, when for example MIMO schemes using a fixed precoding matrix are not supported, then the MIMO_PATTERN#1 is not needed. Also, when multiple precoding matrices are not required, the 1-bit information can be used instead of the 2-bit information. Also, two or more bits can be used when multiple precoding matrices are available.
The same principles apply to the MIMO_PATTERN#2 information. When the transmission scheme does not require multiple schemes to perform a phase shift on the precoded signals (or the precoded signals having shifted basebands), the 1-bit information can be used instead of the 2-bit information. Also, two or more bits can be used when multiple phase shift schemes are available.
Furthermore, although the present embodiment describes a transmission device having two antennas, no limitation in this regard is intended. control information
<img file="MX385274B_D0388.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
380 it can also be transmitted using more than two antennas. In such circumstances, the number of bits in each type of control information can be increased as required in order to perform transmission using four antennas. The above description of the transmission of the control information in the symbol P1 and in the first and second signaling data also applies in such cases.
While Figure 77 illustrates the frame configuration for groups of PLP symbols transmitted by the broadcast station that are divided with respect to the time domain, the following variation is also possible.
Unlike Fig. 77, Fig. 79 illustrates an example of a scheme for arranging symbol streams si and stream 2 in the time-frequency domain, after symbol Pl, first and second signaling data, and the common PLP.
In Figure 79, the symbols labeled #1 are the symbols in the PLP#1 symbol group of Figure 77. Similarly, the symbols labeled #2 are the symbols in the PLP#2 symbol group, the symbols labeled #3 are the symbols from the PLP#3 symbol group, and symbols labeled #4 are the symbols from the PLP#4 symbol group, all from Figure 77. As in Figure 77, PLP#1 is used to transmit data using a spatial multiplexing MIMO system as illustrated in Figure 23, or using a MIMO system with a
<img file="MX385274B_D0389.tif" />
381
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY fixed precoding matrix. PLP#2 is used to transmit data using only a modulated signal. PLP#3 is used to transmit data using a transmission scheme in which a phase shift is performed on the pre-encoded signals (or the pre-encoded signals having shifted base bands). PLP#4 is used to transmit data using space-time block codes.
In Figure 79, when both si and s2 have a symbol on the same subcarrier at the same date-time, one symbol from each of the two streams is present on the common frequency. As explained in other embodiments, when using a transmission scheme involving the mode of a phase shift in the pre-encoded signals (or the pre-encoded signals having shifted basebands), the phase shift may be performed in addition to the weighting using the precoding matrix (and if applicable after changing the baseband signal). Consequently, the signals zl and z2 are obtained. Each of the signals zl and z2 goes out through a different antenna.
As described above, Figure 79 differs from Figure 77 in that the PLPs are partitioned with respect to the time domain. Also, Figure 79 has multiple PLPs arranged with respect to the time and frequency domains. That is, for example, the symbols for PLP#1 and PLP#2 are at date-time 1, while the symbols for PLP#3 and PLP#4 are at date-time 3. As such, PLP symbols that have a different index (#X, where X = 1, 2, and so on) can
<img file="MX385274B_D0390.tif" />
382
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY be assigned to each symbol (composed of a date-time and a subcarrier).
Although for the sake of simplicity Figure 79 lists only #1 and #2 in date-time 1, no limitation in this regard is intended. Indices of the PLP symbols, other than #1 and #2, may be in date-time #1. Furthermore, the relationship between the PLP indices and the subcarriers at date-time 1 is not limited to what is illustrated in Fig. 79. The indices of any PLP symbols can be assigned to any subcarrier. The same applies to other date-times, where the indices of any PLP symbols can be assigned to them.
Unlike Fig. 77, Fig. 80 illustrates an example of a scheme for arranging symbol streams si and stream 2 in the time-frequency domain, after symbol Pl, first and second signaling data, and the common PLP. The characteristic feature of Figure 80 is that, assuming the use of multiple antennas for transmission is the basis of the PLP transmission scheme, then transmission using only stream 1 is not an option for frame T2.
Therefore, in FIG. 80, the PLP symbol group 8001 transmits the data using a spatial multiplexing MIMO system or a MIMO system using a fixed precoding matrix. Also, the symbol group 8002 of the
<img file="MX385274B_D0391.tif" />
383
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
PLP#2 transmits data using a transmission scheme that performs a phase shift on the pre-encoded (or pre-encoded and shifted) signals. Also, symbol group 8003 of PLP#3 transmits the data using a space-time block code. The PLP symbol group following the 8003 symbol group of PLP#3 transmits the data using one of these schemes, namely, using a spatial multiplexing MIMO system or a MIMO system using a fixed precoding matrix, using a transmission that performs a phase shift on the precoded (or precoded and changed) signals or using space-time block codes.
Unlike Fig. 79, Fig. 81 illustrates an example of a scheme for arranging symbol streams si and stream 2 in the time-frequency domain, after symbol Pl, first and second signaling data, and the common PLP.
In Figure 81, the symbols labeled #1 are symbols from the PLP#1 symbol group of Figure 80. Similarly, the symbols labeled #2 are symbols from the PLP#2 symbol group, the symbols labeled #3 are symbols from the PLP#3 symbol group and the symbols labeled #4 are symbols from the PLP#4 symbol group, all from figure 80. As in Figure 80, PLP#1 is used to transmit the data using a spatial multiplexing MIMO system as illustrated in Figure 23 or using a MIMO system with a matrix of
<img file="MX385274B_D0392.tif" />
384
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY fixed precoding. PLP#2 is used to transmit the data using a transmission scheme in which a phase shift is performed on the pre-encoded signals (or the pre-encoded signals having shifted base bands). PLP#3 is used to transmit the data using the space-time block codes.
In Figure 81, when both si and s2 have a symbol on the same subcarrier at the same date-time, one symbol from each of the two streams is present on the common frequency. As explained in other embodiments, when using a transmission scheme involving the mode of a phase shift in the pre-encoded signals (or the pre-encoded signals having shifted basebands), the phase shift may be performed in addition to the weighting using the precoding matrix (and if applicable after changing the baseband signal). Consequently, the signals zl and z2 are obtained. Each of the signals zl and z2 goes out through a different antenna.
As described above, Figure 81 differs from Figure 80 in that the PLPs are partitioned with respect to the time domain. Furthermore, Figure 81 has multiple PLPs arranged with respect to the time and frequency domains. That is, for example, the symbols of PLP#1 and PLP#2 are both at date-time 1. As such, PLP symbols that have a different index (#X, where X = 1, 2, and so on) can be assigned to each symbol (composed of a date-time and a
<img file="MX385274B_D0393.tif" />
385
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY subcarrier).
Although for the sake of simplicity, FIG. 81 lists only #1 and #2 in date-time 1, no limitation in this regard is intended. Indices of the PLP symbols, other than #1 and #2, may be in date-time #1. Also, the relationship between the PLP indices and the subcarriers at date-time 1 is not limited to what is illustrated in Fig. 81. The indices of any PLP symbols can be assigned to any subcarrier. The same applies to other date-times, where the indices of any PLP symbols can be assigned to them. On the other hand, a date-time can also have symbols from only one PLP assigned to it, as is the case for date-time 3. In other words, any assignment of the PLP symbols in the time-frequency domain is allowed. .
Thus, since the frame unit does not include the PLPs that use transmission schemes that only transmit the si stream, the dynamic range of the signals received by the terminal can be restricted, which probably leads to improving the quality of the received signal. .
Although Fig. 81 is described using examples where one is selected to transmit the data using a spatial multiplexing MIMO system or a MIMO system using a fixed precoding matrix, transmission data using a transmission scheme that performs a change of phase in the pre-encoded signals (or in the pre-encoded and changed) and data of
<img file="MX385274B_D0394.tif" />
386
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY transmission that use space-time block codes, the selection of the transmission scheme is not limited to these. Other possibilities include:
select one to transmit data that uses a transmission scheme that performs a phase shift on the precoded (or precoded and changed) signals, transmit data using space-time block codes, and transmit data using a MIMO system that uses a matrix fixed precoding;
select one to transmit data that uses a transmission scheme that performs a phase shift on the precoded signals (or both precoded and changed) and transmit data using space-time block codes; and selecting one to transmit data using a transmission scheme that performs a phase shift on the precoded signals (or both precoded and changed) and transmitting data using a MIMO system using a fixed precoding matrix.
While the above explanation is given for a frame unit having multiple PLPs, the following describes a frame unit having only one PLP.
Figure 82 illustrates an exemplary frame configuration for streams si and stream s2 in the time-frequency domain where the frame unit has only one PLP.
Although Figure 82 indicates control symbols, these are equivalent to the P1 symbol described above and to the
<img file="MX385274B_D0395.tif" />
387
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY first and second signage data. In Figure 82, slot 1 is used to transmit a first frame unit, slot 2 is used to transmit a second frame unit, slot 3 is used to transmit a third frame unit, and slot 4 is used to transmit a third frame unit. transmit a fourth frame unit.
Also, the first frame unit in Fig. 82 transmits symbol group 8101 of PLP#1-1. The transmission scheme is spatial multiplexing MIMO or MIMO using a fixed precoding matrix.
The second frame unit transmits symbol group 8102 of PLP#2-1. The transmission scheme is a transmission using a single modulated signal.
The third frame unit transmits symbol group 8103 of PLP#3-1. The transmission scheme is a transmission scheme that performs a phase shift on the precoded (or precoded and shifted) signals.
The fourth frame unit transmits symbol group 8104 of PLP#4-1. The transmission scheme is the transmission using the space-time block codes.
In Figure 82, when both si and s2 have a symbol on the same subcarrier at the same date-time, one symbol from each of the two currents is present on the common frequency. When using a transmission scheme that involves the mode of a phase shift in the pre-encoded signals (or pre-encoded signals having shifted basebands), the phase shift
<img file="MX385274B_D0396.tif" />
388
IMPI
phase can be performed in addition to weighting using the precoding matrix (and if applicable after changing the baseband signal). Consequently, the signals zl and z2 are obtained. Each of the signals zl and z2 goes out through a different antenna.
As such, the transmission scheme can be established by taking the transmit data rate and the receive data rate of the terminal into consideration for each PLP. This has the dual merit of allowing data transmission speed to be improved and ensuring high data reception quality. The configuration scheme for the control information related to the transmission scheme and so on for the symbol P1 and for the first and second signaling data can be as shown in Tables 2 to 5, thus obtaining the same effects. The frame configuration of Fig. 82 differs from those of Figs. 77 and the like, where each frame unit has multiple PLPs and where control information related to the transmission scheme is required for each of the PLPs. In Fig. 82, each frame unit has only one PLP and so the only control information needed is for transmission information and so on related to that single PLP.
The present embodiment describes a scheme applicable to a system using a DVB standard and in which the transmission scheme involves the modality of a phase change in the pre-encoded signals (or the pre-encoded signals having
<img file="MX385274B_D0397.tif" />
389
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY changed base bands). The transmission scheme involving the mode of a phase change in the pre-encoded signals (or the pre-encoded signals having changed base bands) is described in the present description. Although the present embodiment uses "control symbol" as a technical term, this term has no influence on the present invention.
The following describes the space-time block codes that are described in the present description and that are included in the present embodiment.
Figure 94 illustrates the configuration of a modulated signal using space-time block codes. As shown, a space-time block encoder 9402 takes a baseband signal based on a modulated signal as input. For example, the space-time block encoder (9402) takes the symbol si, the symbol s2, and so on as input. Then, as shown in figure 94, space-time block coding is performed, resulting in zl (9403A) which takes si as symbol #0, -s2* as symbol #1, s3 as symbol #2, -s4 * as token #3 and so on and z2 (9403B) which takes s2 as token #0, si* as token #1, s4 as token #2, s3* as token #3 and so on. Here, the symbol #X of zl and the symbol #X of z2 are simultaneous signals on a common frequency with each communication broadcast from a different antenna. The arrangement of symbols in space-time block codes is not restricted to the time domain. A group
<img file="MX385274B_D0398.tif" />
390
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY symbols may also be arranged in the frequency domain or in the time-frequency domain, as required. Also, the space-time block coding scheme of Fig. 94 is given as an example of space-time block codes. Other space-time block codes can also be applied to each embodiment described in the present description.
E2 modality
The present modality describes a reception scheme and a reception device applicable to a communication system that uses the DVB-T2 standard when the transmission scheme described in the modality is used, which implies the modality of a phase change in the signals. precoded (or in the precoded and changed).
Figure 86 illustrates an exemplary configuration of a receiving device in a terminal used when the transmitting device of the broadcasting station of Figure 76 applies a transmission scheme involving a phase shift of the pre-encoded signals (or the precoded signals having shifted basebands). Components thereof that operate identically to those in Figure 7 use the same reference numerals as therein.
In Fig. 86, a P1 symbol detector and decoder 8601 receive the signals transmitted by the broadcast station and take the baseband signals 704_X and 704_Y as
<img file="MX385274B_D0399.tif" />
391
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY input, thereby performing signal detection and frequency synchronization. The P1 symbol detector and decoder 8601 simultaneously obtain the control information included in the P1 symbol (performing demodulation and error correction decoding thereof) and output the P1 symbol control information 8602 thus obtained.
The OFDM-related processors 8600_X and 8600_Y take the control information of the P1 symbol 8602 as input and modify the OFDM signal processing scheme (such as Fourier transform) accordingly. (This is possible because as described in the El mode, the signals transmitted by the broadcast station include the transmission scheme information in the symbol Pl.) The OFDM-related processors 8600_X and 8600_Y then output the baseband signals 704_X and 704_Y after demodulating it according to the signal processing scheme.
An 8603 P2 symbol demodulator (which can also be applied to PLP signaling) takes the 704 X and 704_Y baseband signals and 8602 Pl symbol control information as input, performs signal processing and demodulation (including error correction decoding) according to the symbol control information Pl and outputs the symbol control information P2 8604.
An 8605 control information generator takes the
<img file="MX385274B_D0400.tif" />
392
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY control information of symbol Pl 8602 and control information of symbol P2 8604 as input, packs the control information (related to receiving operations) and outputs control signal 8606. Then, as shown in figure 86, the control signal 8606 is the input of each component.
A signal processor 711 takes signals 706_l, 706 2, 708_l, 708_2, 704_X, and 704_Y, as well as control signal 8606, as input, performs demodulation decoding according to the information included in the decoding signal. control 8606 and output received data 712. The information included in the control signal is related to the transmission scheme, the modulation scheme, the error correction coding scheme and the coding rate thereof, the block size of the error correction code, and so on. successively used for each PLP.
When the transmission scheme used for PLPs is a spatial multiplexing MIMO, a MIMO using a fixed precoding matrix, and a transmission scheme that performs a phase shift on the precoded (or precoded and shifted) signals, demodulation is performed by obtaining the received (baseband) signals using the output of the channel estimators (705_l, 705_2, 707_l and 707_2) and the relationship between the received (baseband) signals and the transmitted signals. When the transmission scheme involves the
<img file="MX385274B_D0401.tif" />
393
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY modality of a phase change in the precoded signals (or the precoded signals that have changed base bands), the demodulation is performed using the output of the channel estimators (705_l, 705_2, 707_l, and 707_2) , the signals (baseband) received and the relationship given by Mathematics 48 (Equation 48).
Figure 87 illustrates an exemplary configuration of a receiving device at a terminal, which is used when the transmitting device of the broadcasting station of Figure 85 applies a transmission scheme involving a phase shift of pre-encoded signals (or the signals pre-encoded that have shifted basebands). Components therein that operate identically to those in Figures 7 and 86 use the same reference numerals as therein.
The receiving device in figure 87 differs from that in figure 86 in that, while the latter receives data from signals that comply with the DVB-T2 standard and other standards, the former receives data only from signals that comply with the DVB-T2 standard and other standards. conformance to a different standard than DVB-T2.
In Fig. 87, a P1 symbol detector and decoder 8601 receive the signals transmitted by the broadcasting station and take the baseband signals 704_X and 704_Y as input, thereby performing signal detection and frequency synchronization. The 8601 Pl symbol detector and decoder simultaneously obtain the control information included in the Pl symbol (performing demodulation and
<img file="MX385274B_D0402.tif" />
394
IMPI»
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY error correction decoding thereof) and outputs the control information of the symbol P1 8602 thus obtained.
The OFDM-related processors 8600_X and 8600_Y take the control information of the P1 symbol 8602 as input and modify the OFDM signal processing scheme accordingly. (This is possible because as described in the El mode, the signals transmitted by the broadcast station include the transmission scheme information in the symbol Pl.) The OFDM-related processors 8600_X and 8600_Y then output the baseband signals 704_X and 704_Y after demodulating it according to the signal processing scheme.
A first and second signaling data demodulator 8701 (which can also be applied to PLP signaling) takes the baseband signals 704_X and 704_Y and the control information of the symbol Pl 86 02 as input, performs signal processing and demodulation (including error correction decoding) according to the control information of the symbol Pl and outputs the control information of the first and second signaling data 8702.
A control information generator 8605 takes the control information of the Pl symbol 8602 and the control information of the first and second signaling data 8702 as input, packages the control information (related to receive operations), and outputs a control signal 8606.
<img file="MX385274B_D0403.tif" />
395
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
So, as shown in figure 86, the control signal 8606 is the input of each component.
A signal processor 711 takes the signals 706_l, 706_2, 708_l, 708_2, 704_X, and 704__Y, as well as the control signal 8606 as input, performs demodulation decoding according to the information included in the control signal 8606 and outputs received data 712. The information included in the control signal is related to the transmission scheme, the modulation scheme, the error correction coding scheme and the coding rate thereof, the block size of the error correction code, and so on. successively used for each PLP.
When the transmission scheme used for PLPs is a spatial multiplexing MIMO, a MIMO using a fixed precoding matrix, and a transmission scheme that performs a phase shift on the precoded (or precoded and shifted) signals , the demodulation is performed by obtaining the signals (baseband) received using the output of the channel estimators (705_l, 705_2, 707_l, and 707_2) and the ratio between the received (baseband) signals and the transmitted signals. When the transmission scheme involves the mode of a phase shift in the precoded signals (or the precoded signals having shifted basebands), the demodulation is performed using the output of the channel estimators (705_l, 705_2, 707_l, and 707_2 ), the signals (baseband)
<img file="MX385274B_D0404.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
396 received, and the relationship given by Mathematics 48 (Equation 48).
Figure 88 illustrates the configuration of a terminal reception device compatible with the DVB-T2 standard and with standards other than DVB-T2. Components therein that operate identically to those in Figures 7 and 86 use the same reference numerals as therein.
Figure 88 differs from Figures 86 and 87 in that the receiving device of the latter is compatible with signals conforming to the DVB-T2 standard as well as signals conforming to other standards. As such, the receiving device includes a symbol P2 or a demodulator of the first and second signaling data 8801, in order to allow demodulation.
The P2 symbol or first and second signaling data demodulator 8801 takes the baseband signals 704_X and 704_Y, as well as the P1 symbol control information 8602 as input, uses the P1 symbol control information to determine whether the received signals comply with the DVB-T2 standard or with another standard (for example, using the Table in such a determination), performs signal processing and demodulation (including error correction decoding) and outputs control information 8802, which includes information indicating the standard to which received signals conform.
<img file="MX385274B_D0405.tif" />
397
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
Otherwise, the operations are identical to those explained by figures 86 and 87.
A receiving device configured as described in the previous embodiment and receiving the signals transmitted by a broadcast station having the transmission device described in the embodiment El, provides a higher quality of received data by applying the appropriate signal processing. In particular, when receiving signals that are transmitted using a transmission scheme that involves a phase shift applied to the pre-encoded signals (or the pre-encoded signals having shifted basebands), the effectiveness of data transmission as well as the quality of the signal are both enhanced in the LOS environment.
Although the present embodiment is described as a receiving device compatible with the transmission scheme described in embodiment El and therefore having two antennas, no limitation in this respect is intended. The receiving device may also have three or more antennas. In such cases, the reception quality of the data can be further improved by improving the diversity gain. Also, the broadcast station transmitting device may have three or more transmitting antennas and transmit three or more modulated signals. The same effects are achieved by correspondingly increasing the number of antennas in the receiving device of the terminal. Alternatively, the receiving device may have a single antenna and apply
<img file="MX385274B_D0406.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
398 the maximum probability detection or the maximum approximate probability detection. In such circumstances, the transmission scheme is preferably one that involves a phase shift of pre-encoded signals (or pre-encoded signals having shifted base bands).
Such a transmission scheme need not be limited to the specific schemes explained in the present description. As long as precoding occurs and is preceded or followed by a phase change, the same results are obtained for the present embodiment.
E3 mode
The El modality system as applied to the DVB-T2 standard, a transmission scheme involving a phase shift performed on pre-encoded signals (or pre-encoded signals having shifted base bands) includes the control information indicated by the scheme of pilot insertion in the L1 presignaling information. The present embodiment describes a scheme that applies a transmission scheme involving a phase change performed on the pre-encoded signals (or the pre-encoded signals having changed base bands) when the pilot insertion scheme in the L1 pre-signaling information is changed.
Figures 89A, 89B, 90A and 90B illustrate exemplary frame configurations that conform to the DVB-T2 standard in the time-frequency domain
<img file="MX385274B_D0407.tif" />
399
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY in which a common frequency region is used in a transmission scheme whereby multiple modulated signals are transmitted from multiple antennas. Here the horizontal axis represents frequency, i.e. carrier numbers while the vertical axis represents time. Figures 89A and 90A illustrate frame configurations for the modulated signal zl while Figures 89B and 90B illustrate frame configurations for the modulated signal z2, where both are as explained in the previous embodiments. Carrier numbers are labeled fO, fl, f2, and so on, while time is labeled ti, t2, t3, and so on. Also, symbols indicated on the same carrier and time are simultaneously symbols on a common frequency.
Figures 89A, 89B, 90A and 90B illustrate examples of pilot symbol insertion positions that conform to the DVB-T2 standard. (In DVB-T2, eight pilot insertion methods are possible when using multiple antennas to transmit multiple modulated signals. Two of these are currently illustrated). Two types of symbols are indicated, namely pilot symbols and data symbols. As described for other modes, when the transmission scheme involves the mode of a phase shift in the precoded signals (or precoded signals having shifted basebands) or involves precoding using a fixed precoding matrix, then the symbols of data of the modulated signal zl are symbols
<img file="MX385274B_D0408.tif" />
400
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY of the streams si and stream s2 that underwent a weighting, such as the data symbols of the modulated signal z2 . (However, a phase change is also done when the transmission scheme implies that it is done). When space-time block codes or a spatial multiplexing MIMO system are used, the data symbols of the modulated signal zl are the symbols of either stream si or stream s2, as are the symbols of the modulated signal z2 . In Figures 89A, 89B, 90A and 90B, the pilot symbols are labeled with an index that is either PP1 or PP2. These represent the pilot symbols that use different configuration schemes. As described above, eight pilot insertion methods are possible in DVB-T2 (varying in terms of the frequency at which the pilot symbols are inserted into the frame), one of which is indicated by the broadcast station. Figures 89A, 89B, 90A and 90B illustrate two pilot insertion schemes among these eight. As described in the El mode, the information related to the pilot insertion scheme selected by the broadcasting station is transmitted to the receiving terminal as the presignaling data L1 in the symbol P2 .
The following describes an implementation scheme of a transmission scheme involving a phase shift performed on the pre-encoded signals (or the pre-encoded signals having shifted base bands) that complements the transmission scheme.
<img file="MX385274B_D0409.tif" />
401
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY pilot insertion. In this example, the transmission scheme involves preparing ten different phase shift values, namely F[0], F[l], F[2], F[3], F[4], F[5], F[6] , F[7] , F[8] and F[9]. Figures 91A and 91B illustrate the allocation of these phase shift values in the time-frequency domain frame configuration of Figures 89A and 89B when applying a transmission scheme involving a phase shift performed on the pre-encoded signals ( or precoded signals having shifted basebands). Similarly, Figures 92A and 92B illustrate the allocation of these phase shift values in the time-frequency domain frame configuration of Figures 90A and 90B when applying a transmission scheme involving a phase shift performed in the precoded signals (or the precoded signals having shifted basebands). For example, Figure 91A illustrates the frame configuration of the modulated signal zl while Figure 91B illustrates the frame configuration of the modulated signal z2. In both cases, symbol #1 in fl,ti is a symbol in which the frequency modification was performed using a phase shift value F[l] . Therefore, in Figures 91A, 91B, 92A and 92B, a symbol on carrier fx (where x = 0, 1, 2 and so on), a time ty (where y = 1, 2, 3 and so on) is labeled #Z to indicate that the frequency modification was performed using the phase shift value F[Z] in the symbol fx, ty.
Naturally, the insert method (interval of
<img file="MX385274B_D0410.tif" />
402
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY insert) for the frequency-time frame configuration of Figures 91A and 91B differs from that of Figures 92A and 92B. The transmission scheme in which a phase shift is performed on the precoded signals (or the precoded signals having shifted basebands) does not apply to the pilot symbols. Thus, although the same transmission scheme involves a phase shift performed on the same synchronized precoded signals (or the precoded signals having shifted basebands) (for which a different number of phase shift values may have been prepared ), the phase shift value assigned to a single symbol on a given carrier and time in Figures 91A and 91B may be different in Figures 92A and 92B. This is made clear by referring to the figures. For example, the symbol at f5, t2 in Figs. 91A and 91B is labeled #7, indicating that a phase shift has been performed on it using the phase shift value F[7]. On the other hand, the symbol at f5, t2 in Figs. 92A and 92B is labeled #8, indicating that a phase shift has been performed on it using the phase shift value F[8] .
Therefore, although the broadcasting station transmits the control information indicating the pilot pattern (pilot insertion method) in the pre-signaling information Ll, when the transmission scheme selected by the broadcasting station's scheme
<img file="MX385274B_D0411.tif" />
403
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY implies a phase shift performed on the pre-encoded signals (or the pre-encoded signals having shifted basebands), the control information may further indicate the phase shift value assignment scheme used in the selected scheme by the control information given by Table 3 or Table 4. Thus, the reception device of the terminal that receives the modulated signals transmitted by the broadcasting station has the capacity to determine the assignment scheme of the phase change value, obtaining the control information that indicates the pilot pattern in the L1 presignalling data. . (This assumes that the transmission scheme selected by the broadcast station for the PLP transmission of Table 3 or Table 4 is one that involves a phase shift in the pre-encoded signals (or pre-encoded signals having shifted base bands).) Although the above description uses the example of the L1 presignalling data, the control information described above can also be included in the first and second signaling data when P2 symbols are not used, as described for figure 83.
The following describes examples of additional variants. Table 6 lists exemplary phase shift patterns and modulation schemes.
<img file="MX385274B_D0412.tif" />
404
IMPI
corresponding MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY.
Table 6
<td>No. of modulated signals</td><td>Modulation Scheme</td><td>pattern change phase</td>
<td> 2</td><td>#1:QPSK, #2:QPSK</td><td>#1:-, #2:A</td>
<td> 2</td><td>#1:QPSK, #2:16-QAM</td><td>#1: #2:B</td>
<td> 2</td><td>#1:16-QAM, #2:16-QAM</td><td>#1: #2:C</td>
For example, as shown in Table 6, when the modulation scheme is indicated and the phase shift values to be used in the transmission scheme involving a phase shift performed on the pre-encoded signals ( or pre-encoded signals having shifted basebands), the principles described above apply. That is, transmitting only the control information related to the pilot pattern, the PLP transmission scheme, and the modulation scheme is sufficient to allow the receiving device of the terminal to estimate the phase shift value allocation scheme ( in the time-frequency domain) obtaining this control information. In Table 6, the phase change scheme column lists a dash to indicate no phase change is performed and lists #A, #B, or #C to indicate phase change schemes #A, #B, and #C. Similarly, as shown in Table 1, when indicated
<img file="MX385274B_D0413.tif" />
405
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY the modulation scheme and the error correction coding scheme and the phase shift values to be used in the transmission scheme involving a phase shift of pre-encoded signals (or pre-encoded signals that have shifted basebands), then transmit only the control information related to the pilot pattern, the PLP transmission scheme, the modulation scheme and error correction codes in the P2 symbol is sufficient to allow the receiving device of the terminal to estimate the phase shift value allocation scheme (in the time-frequency domain) by obtaining this information of control.
However, unlike Table 1 and Table 6, two or more different types of transmission schemes involving a phase shift performed on the pre-encoded signals (or the pre-encoded signals having shifted basebands) can be selected even though the modulation scheme has been determined. (For example, transmission schemes may have a different period (cycle), or use different phase shift values). Alternatively, two or more different types of transmission scheme involving a phase shift performed on the pre-encoded signals (or the pre-encoded signals having shifted basebands) may be selected, even though the modulation scheme and the error correction scheme. In addition, two or more different types of transmission schemes involving a change of transmission can be selected.
<img file="MX385274B_D0414.tif" />
406
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY stage performed on the pre-encoded signals (or the pre-encoded signals having shifted base bands), even though the error correction scheme has been determined. In such cases, as shown in Table 4, the transmission scheme involves switching between the phase shift values. However, information related to the allocation scheme of the phase shift values (in the time-frequency domain) can also be transmitted.
Table 7 lists examples of control information configuration for information related to such allocation schemes.
Table 7
<td>PHASE_FRAME_ARRANGEMENT (2-bit)</td><td>control information</td>
<td> 00</td><td>assignment scheme #1</td>
<td> 01</td><td>allocation scheme #2</td>
<td> 10</td><td>assignment scheme #3</td>
<td> 11</td><td>assignment scheme #4</td>
For example, assume that the transmitting device at the broadcast station selects Figures 89A and 89B as the pilot pattern insertion scheme and selects transmission scheme A, which involves a phase shift in the pre-encoded signals (or signals). precoded having shifted basebands) ). Thus, the transmitting device may select Figures 91A and 91B or Figures 93A and 93B as the phase shift value assignment scheme (in the domain).
<img file="MX385274B_D0415.tif" />
407
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY time-frequency). For example, when the transmitting device selects figures 91A and 91B, the PHASE_FRAME_ARRANGEMENT information in Table 7 is set to 00. When the transmitting device selects figures 93A and 93B, the PHASE_FRAME_ARRANGEMENT information is set to 01. As such, the receiving device has the ability to determine the phase shift value allocation scheme (in the time-frequency domain) by obtaining the control information from Table 7. The control information from Table 7 is also 10 applicable to transmit by means of the symbol P2 and to transmit by means of the first and second signaling data.
As described above, a phase shift value allocation scheme of the transmission scheme 15 involves a phase shift performed on the pre-encoded signals (or the pre-encoded signals having shifted base bands) which can be performed via the transfer scheme. pilot insertion. Furthermore, by reliably transmitting such allocation scheme information to the receiving party, the receiving device obtains the double benefit of improving data transmission efficiency and improving received signal quality.
Although the present embodiment describes a broadcast station using two transmission signals, the same applies to broadcast stations using one transmission device.
<img file="MX385274B_D0416.tif" />
408
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY that has three or more transmission antennas transmitting three or more signals. It is not necessary to limit the transmission scheme to the specific schemes explained in the present description. As long as precoding occurs and is preceded or followed by a phase change, the same results are obtained for the present embodiment.
The pilot signal configuration scheme is not limited to the present embodiment. When the transmission scheme involves the modality of a phase shift in the precoded signals (or precoded signals having shifted basebands), the receiving device need only implement the relationship given by Math 48 (Equation 48) (for example , the receiving device may know the pilot pattern signals transmitted by the transmitting device in advance). This applies to all embodiments described in the present description.
The transmission devices related to the present invention, as illustrated in figures 3, 4, 12, 13, 51, 52, 67, 70, 76, 85 and so on transmit two modulated signals, namely a modulated signal #1 and a modulated signal #2, on two different transmitting antennas. The average transmit power of modulated signals #1 and #2 can be set freely. For example, when each of the two modulated signals has a power of
<img file="MX385274B_D0417.tif" />
409
IMPI
different average transmission rates, the conventional transmission power control technology used in wireless transmission systems can be applied to them. Therefore, the average transmit power of modulated signals #1 and #2 may differ. In such circumstances, transmit power control may be applied to the baseband signals (for example, when the correlation is performed using the modulation scheme) or it may be performed by means of a power amplifier immediately prior to transmission. the antenna.
Industrial Applicability
The present invention is widely applicable to wireless systems that transmit multiple different modulated signals from multiple antennas, such as an OFDM-MIMO system. Furthermore, in a wired communication system with multiple transmission locations (such as a PLC (power line communication) system, an optical communication system or a DSL (digital subscriber line) system, the present invention can be adapted to a MIMO system, where multiple transmission locations are used to transmit multiple modulated signals as described in the present invention. The modulated signals can also be transmitted from multiple transmission locations.
<img file="MX385274B_D0418.tif" />
410
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
<td></td><td>Ready</td><td>of signs of</td><td>reference</td><td></td>
<td></td><td>302A,</td><td>302B</td><td>encoders</td><td></td>
<td></td><td>304A,</td><td>304B</td><td>interpolators</td><td></td>
<td></td><td>306A,</td><td>306B</td><td>Correlators</td><td></td>
<td> 5</td><td> 314</td><td></td><td>Information Generator</td><td>of</td>
<td></td><td></td><td></td><td>processing scheme</td><td>of</td>
<td></td><td></td><td></td><td>signs</td><td></td>
<td></td><td>308A,</td><td>308B</td><td>Weighting units</td><td></td>
<td></td><td>310A,</td><td>310B</td><td>wireless units</td><td></td>
<td></td><td>312A,</td><td>312B</td><td>antennas</td><td></td>
<td> 10</td><td>317A,</td><td>317B</td><td>phase shifters</td><td></td>
<td></td><td> 402</td><td></td><td>encoder</td><td></td>
<td></td><td> 404</td><td></td><td>Distributor</td><td></td>
<td></td><td>504#l,</td><td> 504#2</td><td>transmission antennas</td><td></td>
<td> 15</td><td>505#l,</td><td> 505#2</td><td>receiving antennas</td><td></td>
<td>1 or</td><td> 600</td><td></td><td>weighting unit</td><td></td>
<td></td><td>701_X,</td><td>701_Y</td><td>antennas</td><td></td>
<td></td><td>703_X,</td><td>703_Y</td><td>wireless units</td><td></td>
<td></td><td>705_l</td><td></td><td>Fluctuation Estimator</td><td>of</td>
<td></td><td></td><td></td><td>channel</td><td></td>
<td> 20</td><td> 705_2</td><td></td><td>Fluctuation Estimator</td><td>of</td>
<td></td><td></td><td></td><td>channel</td><td></td>
<td></td><td>707_l</td><td></td><td>Fluctuation Estimator</td><td>of</td>
<td></td><td></td><td></td><td>channel</td><td></td>
<td></td><td> 707_2</td><td></td><td>Fluctuation Estimator</td><td>of</td>
channel
<img file="MX385274B_D0419.tif" />
411
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
<td></td><td> 709</td><td>information decoder</td>
<td></td><td></td><td>of control</td>
<td></td><td> 711</td><td>signal processor</td>
<td></td><td> 803</td><td>INNER MIMO Detector</td>
<td> 5</td><td>805A, 805B</td><td>calculators of log likelihood</td>
<td></td><td>807A, 807B</td><td>deinterpolators</td>
<td></td><td>809A, 809B</td><td>ratio calculators log likelihood</td>
<td> 10</td><td>811A, 811B</td><td>decoders software input/output</td>
<td></td><td>813A, 813B</td><td>interpolators</td>
<td></td><td> 815</td><td>Memory</td>
<td></td><td> 819</td><td>Coefficient generator</td>
<td> 15</td><td> 901</td><td>decoder software input/output</td>
<td></td><td> 903</td><td>Distributor</td>
<td></td><td>1201A, 1201B</td><td>Related processors with OFDM</td>
<td> 20</td><td>1302A, 1302<sup>a</sup></td><td>Serial to Converters parallel</td>
<td></td><td>1304A, 1304B</td><td>rearranged</td>
<td></td><td>1306A, 1306B</td><td>IFFT Units</td>
<td></td><td>1308A, 1308B</td><td>wireless units</td>
<img file="MX385274B_D0420.tif" />
IMPI
MEXICAN INSTITUTE OF INDUSTRIAL PROPERTY
412
It is stated that in relation to this date, the best method known by the applicant to carry out the present invention is the one that is clear from the present description of the invention.
Contents565
432 sheets
Sheet 1 Sheet 2 Sheet 3 Sheet 4 Sheet 5 Sheet 6 Sheet 7 Sheet 8 Sheet 9 Sheet 10 Sheet 11 Sheet 12 Sheet 13 Sheet 14 Sheet 15 Sheet 16 Sheet 17 Sheet 18 Sheet 19 Sheet 20 Sheet 21 Sheet 22 Sheet 23 Sheet 24 Sheet 25 Sheet 26 Sheet 27 Sheet 28 Sheet 29 Sheet 30 Sheet 31 Sheet 32 Sheet 33 Sheet 34 Sheet 35 Sheet 36 Sheet 37 Sheet 38 Sheet 39 Sheet 40 Sheet 41 Sheet 42 Sheet 43 Sheet 44 Sheet 45 Sheet 46 Sheet 47 Sheet 48 Sheet 49 Sheet 50 Sheet 51 Sheet 52 Sheet 53 Sheet 54 Sheet 55 Sheet 56 Sheet 57 Sheet 58 Sheet 59 Sheet 60 Sheet 61 Sheet 62 Sheet 63 Sheet 64 Sheet 65 Sheet 66 Sheet 67 Sheet 68 Sheet 69 Sheet 70 Sheet 71 Sheet 72 Sheet 73 Sheet 74 Sheet 75 Sheet 76 Sheet 77 Sheet 78 Sheet 79 Sheet 80 Sheet 81 Sheet 82 Sheet 83 Sheet 84 Sheet 85 Sheet 86 Sheet 87 Sheet 88 Sheet 89 Sheet 90 Sheet 91 Sheet 92 Sheet 93 Sheet 94 Sheet 95 Sheet 96 Sheet 97 Sheet 98 Sheet 99 Sheet 100 Sheet 101 Sheet 102 Sheet 103 Sheet 104 Sheet 105 Sheet 106 Sheet 107 Sheet 108 Sheet 109 Sheet 110 Sheet 111 Sheet 112 Sheet 113 Sheet 114 Sheet 115 Sheet 116 Sheet 117 Sheet 118 Sheet 119 Sheet 120 Sheet 121 Sheet 122 Sheet 123 Sheet 124 Sheet 125 Sheet 126 Sheet 127 Sheet 128 Sheet 129 Sheet 130 Sheet 131 Sheet 132 Sheet 133 Sheet 134 Sheet 135 Sheet 136 Sheet 137 Sheet 138 Sheet 139 Sheet 140 Sheet 141 Sheet 142 Sheet 143 Sheet 144 Sheet 145 Sheet 146 Sheet 147 Sheet 148 Sheet 149 Sheet 150 Sheet 151 Sheet 152 Sheet 153 Sheet 154 Sheet 155 Sheet 156 Sheet 157 Sheet 158 Sheet 159 Sheet 160 Sheet 161 Sheet 162 Sheet 163 Sheet 164 Sheet 165 Sheet 166 Sheet 167 Sheet 168 Sheet 169 Sheet 170 Sheet 171 Sheet 172 Sheet 173 Sheet 174 Sheet 175 Sheet 176 Sheet 177 Sheet 178 Sheet 179 Sheet 180 Sheet 181 Sheet 182 Sheet 183 Sheet 184 Sheet 185 Sheet 186 Sheet 187 Sheet 188 Sheet 189 Sheet 190 Sheet 191 Sheet 192 Sheet 193 Sheet 194 Sheet 195 Sheet 196 Sheet 197 Sheet 198 Sheet 199 Sheet 200 Sheet 201 Sheet 202 Sheet 203 Sheet 204 Sheet 205 Sheet 206 Sheet 207 Sheet 208 Sheet 209 Sheet 210 Sheet 211 Sheet 212 Sheet 213 Sheet 214 Sheet 215 Sheet 216 Sheet 217 Sheet 218 Sheet 219 Sheet 220 Sheet 221 Sheet 222 Sheet 223 Sheet 224 Sheet 225 Sheet 226 Sheet 227 Sheet 228 Sheet 229 Sheet 230 Sheet 231 Sheet 232 Sheet 233 Sheet 234 Sheet 235 Sheet 236 Sheet 237 Sheet 238 Sheet 239 Sheet 240 Sheet 241 Sheet 242 Sheet 243 Sheet 244 Sheet 245 Sheet 246 Sheet 247 Sheet 248 Sheet 249 Sheet 250 Sheet 251 Sheet 252 Sheet 253 Sheet 254 Sheet 255 Sheet 256 Sheet 257 Sheet 258 Sheet 259 Sheet 260 Sheet 261 Sheet 262 Sheet 263 Sheet 264 Sheet 265 Sheet 266 Sheet 267 Sheet 268 Sheet 269 Sheet 270 Sheet 271 Sheet 272 Sheet 273 Sheet 274 Sheet 275 Sheet 276 Sheet 277 Sheet 278 Sheet 279 Sheet 280 Sheet 281 Sheet 282 Sheet 283 Sheet 284 Sheet 285 Sheet 286 Sheet 287 Sheet 288 Sheet 289 Sheet 290 Sheet 291 Sheet 292 Sheet 293 Sheet 294 Sheet 295 Sheet 296 Sheet 297 Sheet 298 Sheet 299 Sheet 300 Sheet 301 Sheet 302 Sheet 303 Sheet 304 Sheet 305 Sheet 306 Sheet 307 Sheet 308 Sheet 309 Sheet 310 Sheet 311 Sheet 312 Sheet 313 Sheet 314 Sheet 315 Sheet 316 Sheet 317 Sheet 318 Sheet 319 Sheet 320 Sheet 321 Sheet 322 Sheet 323 Sheet 324 Sheet 325 Sheet 326 Sheet 327 Sheet 328 Sheet 329 Sheet 330 Sheet 331 Sheet 332 Sheet 333 Sheet 334 Sheet 335 Sheet 336 Sheet 337 Sheet 338 Sheet 339 Sheet 340 Sheet 341 Sheet 342 Sheet 343 Sheet 344 Sheet 345 Sheet 346 Sheet 347 Sheet 348 Sheet 349 Sheet 350 Sheet 351 Sheet 352 Sheet 353 Sheet 354 Sheet 355 Sheet 356 Sheet 357 Sheet 358 Sheet 359 Sheet 360 Sheet 361 Sheet 362 Sheet 363 Sheet 364 Sheet 365 Sheet 366 Sheet 367 Sheet 368 Sheet 369 Sheet 370 Sheet 371 Sheet 372 Sheet 373 Sheet 374 Sheet 375 Sheet 376 Sheet 377 Sheet 378 Sheet 379 Sheet 380 Sheet 381 Sheet 382 Sheet 383 Sheet 384 Sheet 385 Sheet 386 Sheet 387 Sheet 388 Sheet 389 Sheet 390 Sheet 391 Sheet 392 Sheet 393 Sheet 394 Sheet 395 Sheet 396 Sheet 397 Sheet 398 Sheet 399 Sheet 400 Sheet 401 Sheet 402 Sheet 403 Sheet 404 Sheet 405 Sheet 406 Sheet 407 Sheet 408 Sheet 409 Sheet 410 Sheet 411 Sheet 412 Sheet 413 Sheet 414 Sheet 415 Sheet 416 Sheet 417 Sheet 418 Sheet 419 Sheet 420 Sheet 421 Sheet 422 Sheet 423 Sheet 424 Sheet 425 Sheet 426 Sheet 427 Sheet 428 Sheet 429 Sheet 430 Sheet 431 Sheet 432
98 members in 18 offices
Priority claims4
| Document | Office | Kind | Date |
|---|---|---|---|
| 2010276448 | Japan | – | |
| 2011026422 | Japan | – | |
| 2011033770 | Japan | – | |
| 2011051841 | Japan | – |
Members98
| Document | Office | Kind | |
|---|---|---|---|
| CA2803906A1 | Canada | A1 | |
| CA3017181A1 | Canada | A1 | |
| WO2012077299A1 | World Intellectual Property Organization (WIPO) | A1 | |
| TW201240375A | Taiwan Province of China | A | |
| AU2011339962A1 | Australia | A1 | |
| SG187028A1 | Singapore | A1 | |
| PH12013500214A1 | Philippines | A1 | |
| MX2013000954A | Mexico | A | |
| CN103004121A | China | A | |
| AR084168A1 | Argentina | A1 | |
| US2013121306A1 | United States of America | A1 | |
| EA201390044A1 | Eurasian Patent Organization (EAPO) | A1 | |
| CL2013000510A1 | Chile | A1 | |
| EP2651062A1 | European Patent Office (EPO) | A1 | |
| PE20131090A1 | Peru | A1 | |
| KR20130142986A | Republic of Korea | A | |
| JPWO2012077299A1 | Japan | A1 | |
| US8867482B2 | United States of America | B2 | |
| US2015003555A1 | United States of America | A1 | |
| US8989137B2 | United States of America | B2 | |
| US2015155925A1 | United States of America | A1 | |
| US2015381251A1 | United States of America | A1 | |
| US9236923B2 | United States of America | B2 | |
| CN103004121B | China | B | |
| EA201500712A1 | Eurasian Patent Organization (EAPO) | A1 | |
| US9281883B2 | United States of America | B2 | |
| JP5886207B2 | Japan | B2 | |
| CN105450277A | China | A | |
| US2016142118A1 | United States of America | A1 | |
| EA023186B1 | Eurasian Patent Organization (EAPO) | B1 | |
| CN105634570A | China | A | |
| JP2016129373A | Japan | A | |
| AU2011339962B2 | Australia | B2 | |
| AU2016219543A1 | Australia | A1 | |
| US9461725B2 | United States of America | B2 | |
| KR20160140990A | Republic of Korea | A | |
| AU2016265991A1 | Australia | A1 | |
| US2016380683A1 | United States of America | A1 | |
| TWI568206B | Taiwan Province of China | B | |
| IL223919A | Israel | A | |
| TW201724777A | Taiwan Province of China | A | |
| EP2651062A4 | European Patent Office (EPO) | A4 | |
| BR112013002521A2 | Brazil | A2 | |
| US9882618B2 | United States of America | B2 | |
| US2018102820A1 | United States of America | A1 | |
| AU2016219543B2 | Australia | B2 | |
| KR101869357B1 | Republic of Korea | B1 | |
| KR101869778B1 | Republic of Korea | B1 | |
| KR20180069125A | Republic of Korea | A | |
| JP6347371B2 | Japan | B2 | |
| EA030237B1 | Eurasian Patent Organization (EAPO) | B1 | |
| US10038483B2 | United States of America | B2 | |
| TWI634758B | Taiwan Province of China | B | |
| US2018254806A1 | United States of America | A1 | |
| JP2018142996A | Japan | A | |
| SG10201806950YA | Singapore | A | |
| KR20180110234A | Republic of Korea | A | |
| KR101905599B1 | Republic of Korea | B1 | |
| AU2016265991B2 | Australia | B2 | |
| CA2803906C | Canada | C | |
| AU2018247322A1 | Australia | A1 | |
| CN105450277B | China | B | |
| TW201906341A | Taiwan Province of China | A | |
| CN105634570B | China | B | |
| US10305556B2 | United States of America | B2 | |
| KR101998085B1 | Republic of Korea | B1 | |
| US2019229782A1 | United States of America | A1 | |
| JP6598093B2 | Japan | B2 | |
| JP2020017982A | Japan | A | |
| US10644768B2 | United States of America | B2 | |
| US2020235793A1 | United States of America | A1 | |
| TWI706642B | Taiwan Province of China | B | |
| AU2018247322B2 | Australia | B2 | |
| TW202101927A | Taiwan Province of China | A | |
| JP6817597B2 | Japan | B2 | |
| JP2021048637A | Japan | A | |
| TWI729937B | Taiwan Province of China | B | |
| TW202133574A | Taiwan Province of China | A | |
| US11128355B2 | United States of America | B2 | |
| EP2651062B1 | European Patent Office (EPO) | B1 | |
| JP7018574B2 | Japan | B2 | |
| BR112013002521B1 | Brazil | B1 | |
| TWI757174B | Taiwan Province of China | B | |
| EP3965324A2 | European Patent Office (EPO) | A2 | |
| EP3965324A3 | European Patent Office (EPO) | A3 | |
| US2022109471A1 | United States of America | A1 | |
| TW202218355A | Taiwan Province of China | A | |
| US11575412B2 | United States of America | B2 | |
| TWI796934B | Taiwan Province of China | B | |
| EP4170937A1 | European Patent Office (EPO) | A1 | |
| US2023142497A1 | United States of America | A1 | |
| CA3017181C | Canada | C | |
| US11804880B2 | United States of America | B2 | |
| US2024022287A1 | United States of America | A1 | |
| EP4170937B1 | European Patent Office (EPO) | B1 | |
| US12166545B2 | United States of America | B2 | |
| US2025062798A1 | United States of America | A1 | |
| MX385274BThis record | Mexico | B |
Numbers
- Publication
- 385274
- Application
- 2015015185
Titles2
- Spanish
- METODO DE GENERACION DE SEÑALES Y APARATO DE GENERACION DE SEÑALES.
- English
- SIGNAL GENERATION METHOD AND SIGNAL GENERATION APPARATUS.
Classification
- CPC, 15
- H04B7/0413
- H04L5/005
- H04L25/0224
- H04L25/03898
- H04L25/067
- H04B7/0669
- H04B7/0682
- H04B7/0697
- H04L1/004
- G06F11/10
- H04B7/0482
- H04L1/0058
- H04W72/044
- H04B7/0456
- H04L27/2627
- IPC, 2
- H04B7 04
- H04L1 00