Enhancements to the MU-MIMO VHT preamble to enable transmission mode detection
Abstract
This record has no abstract on file.
Term
3.9 yearsto projected expiry
Projected expiry 12 August 2030, counted from filing; an application has no term until it is granted.
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15 claims: 6 independent, 9 dependent
- 1Patent claims Zastrzeżenia patentowe 1. A method of wireless communication, comprising:receiving a first portion of a SIG signal field in a frame structure, the SIG field comprising a first portion that is common to multiple devices and a second portion that is specific to each device;1. Sposób komunikacji bezprzewodowej, obejmujący: odbieranie pierwszej części pola SIG sygnału w strukturze ramki, przy czym pole SIG zawiera pierwszą część, która jest wspólna dla wielu urządzeń oraz drugą część, która jest specyficzna dla każdego urządzenia;determining the transmission mode of the frame structure based on the first portion of the SIG field;and receiving the remainder of the frame structure based on the transmission mode;characterized in that the transmission mode information is received on an orthogonal axis relative to the constellation used to receive the SIG field. określanie trybu transmisji struktury ramki na podstawie pierwszej części pola SIG;i odbieranie pozostałej części struktury ramki na podstawie trybu transmisji;znamienny tym, że informacje trybu transmisji są odbierane na osi ortogonalnej względem konstelacji wykorzystywanej przy odbieraniu pola SIG.
- 5A method of wireless communication, comprising:generating a frame structure comprising a SIG signal field;5. Sposób komunikacji bezprzewodowej, obejmujący: generowanie struktury ramki zawierającej pole SIG sygnału;transmitowanie pierwszej części pola SIG w strukturze ramki, przy czym pierwsza część jest wspólna dla wielu urządzeń, przy czym tryb transmisji struktury ramki jest wykrywalny na podstawie pierwszej części pola SIG, przy czym informacje trybu transmisji są transmitowane na osi ortogonalnej względem konstelacji wykorzystywanej przy transmitowaniu pola SIG;i transmitowanie drugiej części pola SIG w strukturze ramki, przy czym druga część jest specyficzna dla każdego z wielu urzą dzeń . transmitting the first part of the SIG field in the frame structure, the first part being common to many devices, wherein the transmission mode of the frame structure is detectable on the basis of the first part of the SIG field, the transmission mode information being transmitted on an orthogonal axis relative to the constellation used for field transmission SIG;and transmitting the second portion of the SIG field in the frame structure, the second portion being specific to each of the plurality of devices.
- 11A device for wireless communication, comprising:means for receiving a first portion of a SIG signal field in a frame structure, the SIG field comprising a first portion that is common to multiple devices, and a second portion that is specific to each device;11. Urządzenie do komunikacji bezprzewodowej, zawierające: środki do odbierania pierwszej części pola SIG sygnału w strukturze ramki, przy czym pole SIG zawiera pierwszą część, która jest wspólna dla wielu urządzeń, oraz drugą część, która jest specyficzna dla każdego urządzenia;means for determining the transmission mode of the frame structure based on the first portion of the SIG field;the receiving means are further configured to receive the remainder of the frame structure based on the transmission mode;środki do określania trybu transmisji struktury ramki na podstawie pierwszej części pola SIG;środki do odbierania są ponadto skonfigurowane do odbierania pozostałej części struktury ramki na podstawie trybu transmisji;characterized in that the receiving means are further configured to receive transmission mode information on an orthogonal axis relative to the constellation used for receiving the SIG field. znamienne tym, że środki do odbierania są ponadto skonfigurowane do odbierania informacji trybu transmisji na osi ortogonalnej względem konstelacji wykorzystywanej przy odbieraniu pola SIG.
- 13A device for wireless communication, comprising:means for generating a frame structure comprising a SIG signal field;and means for transmitting the first part of the SIG field in the frame structure, the first part being common to multiple devices, wherein the frame structure transmission mode is detectable based on the first part of the SIG field, the means for transmission being further configured to transmit mode information 13. Urządzenie do komunikacji bezprzewodowej, zawierające: środki do generowania struktury ramki zawierającej pole SIG sygnału;i środki do transmitowania pierwszej części pola SIG w strukturze ramki, przy czym pierwsza część jest wspólna dla wielu urządzeń, przy czym tryb transmisji struktury ramki jest wykrywalny na podstawie pierwszej części pola SIG, przy czym środki do transmitowania są ponadto skonfigurowane do transmitowania informacji trybu 53/59P34171PL00 transmisji na osi ortogonalnej względem konstelacji wykorzystywanej przy transmitowaniu pola SIG, i przy czym środki do transmitowania są ponadto skonfigurowane do transmitowania drugiej części pola SIG w strukturze ramki, przy czym druga część jest specyficzna dla każdego z wielu urzą dzeń . Transmission on an orthogonal axis relative to the constellation used for transmitting the SIG field, and wherein the means for transmission are further configured to transmit the second part of the SIG field in the frame structure, the second part being specific for each of the plurality of devices.
- 14The device according to claims 11 or 13, or the method according to claims 1 or 5, wherein the first or second SIG field portion comprises at least one OFDM orthogonal frequency division multiplexing symbol. 14. Urządzenie według zastrzeżeń 11 albo 13, lub sposób według zastrzeżeń 1 albo 5, w którym pierwsza lub druga część pola SIG zawiera co najmniej jeden symbol multipleksowania OFDM z ortogonalnym podziałem częstotliwości.
- 15A computer program product for wireless communications, comprising a computer readable medium containing executable instructions for performing the step of claims 1-10. 15. Produkt w postaci programu komputerowego dla komunikacji bezprzewodowej, obejmujący odczytywalny komputerowo nośnik zawierający wykonywalne instrukcje dla przeprowadzenia etapu według zastrzeżeń 1-10. Qualcomm Incorporated Pełnomocnik:Qualcomm Incorporated Proxy: 53 / 59P34171PL00 53/59P34171PL00 UT Ir120d UT Ir120d FIG. 1 FIG. 1 53 / 59P34171PL00 53/59P34171PL00 53 / 59P34171PL00 53/59P34171PL00 FIG. 3 FIG. 3 53 / 59P34171PL00 53/59P34171PL00 L-CD8 L-CD8 | L-CD81 L-CD8 L-CD8 L-CD8 | STF41 CD4 | CD4 CD4 CD4 CD4 CD4 CD4 ___ | CD4 |> 8 με 8 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με L-CD8 L-CD8 | L-CD81 L-CD8 L-CD8 L-CD8 | STF41 CD4 | CD4 CD4 CD4 CD4 CD4 CD4 ___ | CD4 |> 8 με 8 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με 4 με FIG. 4Α FIG. 4Α 53 / 59P34171PL00 53/59P34171PL00 L-STF L-LTF L-SIG1 HT-SIGIi HT-SiG2i VHT-StG VHT- LTF1 LTFWHTSIG1 Dane Dane Użytkownik 1 L-STF L-LTF L-SIG1 HT-SIGIi HT-SiG2i VHT-StG VHT- LTF1 LTFWHTSIG1 Data Data User 1 L-CD1 L-CD1 L-CD1 L-CD1 L-CD1 L-CD1 STF1 CD1 CD1 CD1 CD1 s L-CD1 L-CD1 L-CD1 L-CD1 L-CD1 L-CD1 STF1 CD1 CD1 CD1 CD1 y 53 / 59P34171PL00 53/59P34171PL00 53 / 59P34171PL00 53/59P34171PL00 53 / 59P34171PL00 53/59P34171PL00 53 / 59P34171PL00 53/59P34171PL00 53 / 59P34171PL00 53/59P34171PL00
Independent claims6
113 paragraphs in 5 sections, as filed
TECHNICAL FIELD [0001] Some aspects of the present invention generally relate to wireless communication, and in particular to detecting the signal transmission mode at a receiver.
BACKGROUND [0002] To address the problem of increasing bandwidth requirements that are placed on wireless communication systems, various schemes are being developed to allow multiple user terminals to communicate with a single access point by sharing channel resources while obtaining high data throughput. Multiple Input or Multiple utput (MIMO) technology is one such approach that has recently become a popular method for next generation communication systems. MIMO technology has been adapted in several emerging wireless communication standards, such as
The Institute of Electrical Engineers and IEEE 802.11 defines the 802.11 Electronics (IEEE) standard set. 802.11 wireless interface (WLAN) standards developed for short-range communication
Local radio standard by the IEEE committee (e.g. from several dozen to several hundred meters).
[0003] The MIMO wireless system uses a specific number (NT) of transmitting antennas and a specified number (NR) of receiving antennas for data transmission. The MIMO channel formed by NT transmit antennas and NR receive antennas can be spread over NS spatial streams, with NS <= min {NT, NR} for all practical purposes. NS spatial streams can be used to transmit NS
53 / 59P34171EN00 independent data streams to obtain greater total data throughput.
[0004] In wireless networks with a single access point and multiple stations, simultaneous transmissions can occur across multiple channels towards different stations, both towards uplink and downlink. [0005] Attention is drawn to US 2006/193340 A1, which describes a modified header that is used by extended devices that operate in mixed-mode environments and undeveloped areas to adapt beamforming for transmissions. In one process, the extended wireless device processes the data for transmitting this data as a packet, wherein the extended wireless device is a device configured to communicate using a standard protocol supported by each node device and using an extended protocol not supported by traditional node devices. If the packet is to be directed to the extended device, the extended wireless device sends the header of the packet, which is useful in the extended mode of the extended devices and useful in the receiving traditional device to determine that the receiving traditional device is not the destination of the data following the header. When the receiving traditional device is expected to introduce a delay in the network, the extended wireless device may shape its signal beam or otherwise differentiate from the traditional protocol in communication with the extended devices.
SUMMARY OF THE INVENTION
[0006] According to the present invention, there is provided a method and apparatus as set out in the independent claims, respectively. Preferred embodiments of the invention are described in the dependent claims.
[0007] Some aspects of the present invention provide a method of wireless communication. The method generally includes receiving a first signal field (SIG) portion of the frame structure, the SIG field comprising a first portion that is common to multiple devices, and a second portion that is specific to each device, determining the transmission mode of the frame structure based on the first portion SIG fields and receiving the remainder of the frame structure based on the transmission mode.
[0008] Some aspects of the present invention provide a method of wireless communication. The method generally includes generating a signal structure comprising a signal field (SIG), transmitting a first part of the SIG field in a frame structure, the first part being common to multiple devices, wherein the transmission mode of the frame structure is detected based on the first part of the SIG field, and transmitting a second parts of the SIG field in the frame structure, the second part being specific to each of the multiple devices.
[0009] Some aspects of the present invention provide a device for wireless communication. The method generally includes a receiver configured to receive a first portion of the signal field (SIG) in the frame structure, the SIG field comprising a first portion that is common to multiple devices and a second portion that is specific to each device, a circuit configured to determine the structure transmission mode frames based on the first part of the SIG field, and wherein the receiver is further configured to receive the remainder of the frame structure based on the transmission mode.
[0010] Some aspects of the present invention provide a device for wireless communication. The method generally includes a circuit configured to generate a signal field (SIG) frame structure, a transmitter configured to transmit the first portion of the SIG field in the frame structure, the first portion being common to multiple devices, wherein the transmission mode of the frame structure is detected based on the first portion the SIG field, and wherein the transmitter is further configured to transmit the second part of the SIG field in the frame structure, the second part is specific to each of the many devices.
[0011] Some aspects of the present invention provide a device for wireless communication. The method generally includes means for receiving a first signal field (SIG) portion of a frame structure, the SIG field comprising a first portion that is common to multiple devices and a second portion that is specific to each device, means for determining the transmission mode of the frame structure on based on the first portion of the SIG field, and wherein the receiving means are further configured to receive the remainder of the frame structure based on the transmission mode.
[0012] Some aspects of the present invention provide a device for wireless communication. The method generally includes means for generating a frame structure comprising a signal field (SIG), means for transmitting the first part of the SIG field in the frame structure, the first part being common to multiple devices, wherein the frame structure transmission mode is detected based on the first part of the SIG field and wherein the means for transmitting is further configured to transmit the second part of the SIG field in the frame structure, the second part is specific to each of the many devices.
[0013] Some aspects of the present invention provide a computer program product for communication
53 / 59P34171EN00 wireless, comprising a computer readable medium containing instructions. These instructions are executable for receiving the first part of the signal field (SIG) in the frame structure, the SIG field comprising a first part that is common to many devices and a second part that is specific to each device, determining the transmission mode of the frame structure based on the first part of the SIG field and receiving the remainder of the frame structure based on the transmission mode.
[0014] Some aspects of the present invention provide a computer program product for wireless communication comprising a computer readable medium containing instructions. These instructions are executable for generating the frame structure including the signal field (SIG), transmitting the first part of the SIG field in the frame structure, the first part being common to many devices, the mode of transmission of the frame structure being detected based on the first part of the SIG field and transmitting the second part of the SIG field in the frame structure, the second part being specific to each of the multiple devices.
[0015] Some aspects provide a station for wireless communication. This station generally comprises at least one antenna, a receiver configured to receive, via at least one antenna, a first signal field (SIG) part in the frame structure, the SIG field comprising a first part which is common to many devices, and a second part , which is specific to each device, a circuit configured to determine the transmission mode of the frame structure based on the first part of the SIG field, and wherein the receiver is further configured to receive the remainder of the frame structure based on the transmission mode.
[0016] Some aspects provide an access point for wireless communication. The access point generally includes a plurality of antennas, a circuit configured to generate a structure
53 / 59P34171EN00 frame comprising a signal field (SIG), a transmitter configured to transmit, via multiple antennas, the first portion of the SIG field in the frame structure, the first portion being common to multiple devices, wherein the frame structure transmission mode is detected based on the first portion of the SIG field, and wherein the transmitter is further configured to transmit the second portion of the SIG field in a frame structure, the second part is specific to each of the many devices.
BRIEF DESCRIPTION OF THE DRAWINGS [0017] In order that the above-mentioned features of the present invention may be understood in detail, a more detailed description is provided, briefly summarized above, by reference to aspects, several of which are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings illustrate only some typical aspects of the present invention and should therefore not be considered as limiting its scope, as the description may match other equally efficient aspects.
FIG. 1 is a diagram of a wireless communication network in accordance with some aspects of the present invention.
FIG. 2 is a block diagram of an exemplary access point and user terminals in accordance with some aspects of the present invention.
FIG. 3 is a block diagram of an exemplary wireless device in accordance with some aspects of the present invention.
FIG. 4A and 4B show the proposed frame structures for a multi-input system - many outputs for many users (MU-MIMO) with very high downlink
Capacity (VHT), in accordance with some aspects of the present invention.
FIG. 5 illustrates the proposed frame structure for an MU-MIMO VHT uplink system in accordance with some aspects of the present invention.
FIG. 6 illustrates example operations for transmitting a frame suitable for mode detection, in accordance with some aspects of the present invention.
FIG. 6A shows examples of components capable of performing the operations shown in FIG. 6.
FIG. 7 depicts example operations for detecting a transmission mode of a received signal at a receiver, in accordance with some aspects of the present invention.
FIG. 7A shows examples of components capable of performing the operations shown in FIG. 7.
DETAILED DESCRIPTION [0018] Various aspects of some embodiments of the present invention are described below. It should be obvious that the solutions presented herein may be implemented in many different forms and that any specific structure, function or both presented herein are merely representations. Based on the solutions provided herein, one of ordinary skill in the art should recognize that the aspect described herein can be implemented independently of any other aspects and that two or more of these aspects can be combined in various ways. For example, a device may be implemented or a method may be utilized using any number of aspects set forth herein. In addition, such a device may be implemented or such a method may be used using other structure, functionality or structure and functionality in addition to or as other than
53 / 59P34171EN00 one or more aspects set forth herein. In addition, the aspect may include at least one element of the claim.
[0019] The term "exemplary" is used herein to mean "serving as an example, example, or illustration." Any aspect described herein as "exemplary" need not necessarily be interpreted as being preferred or favorable over other aspects. The term "traditional stations" also used herein generally refers to wireless network nodes that support the 802.11n standard of the Institute of Electrical and Electronics Engineers (IEEE) or earlier versions of the IEEE standard
802.11.
[0020] The multi-antenna transmission methods described herein can be used in combination with various wireless technologies such as code-division multi-access (CDMA), orthogonal frequency-division multiplexing (OFDM), time-division multi-access (SDMA) and so on (1) (TDMA), multi-access with spatial division further. Many user terminals can transmit / receive data via orthogonal CDMA channels, (2) TDMA time slots, or (3) OFDM subbands. The CDMA system can implement IS-2000, IS-95, IS-856, broadband CDMA (W-CDMA) or some other standards. The OFDM system can implement the IEEE 802.11 standard or some other standards. The TDMA system can implement GSM or some other standards. These various standards are known in the art.
MIMO SYSTEM EXAMPLE [0021] FIG. 1 shows the MIMO 100 multi-access system with access points and user terminals. For simplicity, in FIG. 1 only one point is shown
Access point 110. An access point (AP) is essentially a stationary station that communicates with user terminals and can also be referred to as a base station or by other names. The user terminal may be fixed or mobile and may also be referred to as a mobile station, station (STA), client, wireless device or by other names. The user terminal can be a wireless device, such as a mobile phone, personal digital assistant (PDA), handheld device, wireless modem, laptop computer, personal computer, etc.
[0022] Access point 110 may communicate with one or more user terminals 120 at any given time on the downlink and uplink. The downlink (i.e. the forward link) is the communication link from the access point to the user terminals, and the uplink (i.e. the reverse link) is the communication link from the user terminals to the access point. The user terminal may also communicate in peer-to-peer mode with another user terminal. The system controller 130 is connected to the access points and provides coordination and control.
[0023] System 100 uses a plurality of transmit antennas and a plurality of receive antennas for data transmission on the downlink and uplink. Access point above 110 is equipped with a specific number of antennas. Multiple inputs (MI) for downlink transmission and multiple outputs (MO) for uplink transmission. The Nu set of selected 120 user terminals collectively provides multiple outputs for downlink transmission and multiple inputs for uplink transmission. In cases, it may be desirable for N<sub>ap</sub> -N "
some 1 if the data symbol streams for Nu user terminals are not multiplexed in code, frequency or time by some means. Nu can be greater than Nap if data symbol streams can be multiplexed using different code channels for CDMA, detachable sets
53/59 P34171EN00 subbands for OFDM, and so on. Each selected user terminal transmits user-specific data and / or receives user-specific data from the access point.
In general, each selected user terminal may be equipped with one or more antennas (i.e., N<sub>ut</sub> > 1). N<sub>at </sub>selected user terminals may have the same or a different number of antennas.
[0024] The MIMO 100 system may be a time division duplex system (TDD) or a frequency division duplex system (FDD). For TDD, the downlink and uplink share the same frequency band. For the FDD system, downlink and uplink use different frequency bands. The MIMO 100 system can also use a single carrier or multiple carriers for transmission. Each user terminal can be equipped with a single antenna (e.g. to keep costs low) or multiple antennas (e.g. when additional costs may be incurred).
[0025] FIG. 2 shows a block diagram of the access point 110 and two user terminals 120m and 120x in the MIMO 100 system. Access point 110 is equipped with Nap antennas from 224a to 224ap. The 120m user terminal is equipped with Nut.m antennas from 252ma to 252mu, and the 120x user terminal is equipped with Nut, x antennas from 252xa to 252xu. Access point 110 is a transmitting unit for downlink and a receiving unit for uplink. Each user terminal 120 is a transmitting unit for the uplink and a receiving unit for the downlink. The "transmitting unit" used herein is an independently operating device or device capable of transmitting data via a frequency channel, and the "receiving unit" is an independent operating device or device capable of receiving data via a frequency channel. In the description below, the subscript "dn" means a downlink, the subscript "up" means a uplink, Nup user terminals are selected
For simultaneous uplink transmission, Ndn of user terminals is selected for simultaneous downlink transmission, Nup may or may not be equal to Ndn, and Nup and Ndn may be fixed values or may change for each planning interval. Beam control or some other spatial processing method can be used at the access point and user terminal.
[0026] At the uplink, in each user terminal 120 selected for uplink transmission, the TX data processor 288 receives traffic data from the data source 286 and control data from the controller 280. The TX data processor 288 processes (e.g., encodes, interleaves, and modulates) ) traffic data {dup.m} for the user terminal based on the coding and modulation schemes associated with the rate selected for the user terminal and provides a stream of data symbols {Sup, m}. Spatial processor
TX 290 performs spatial processing on the {Sup, m} data symbol stream and provides Nut, m transmit symbol streams for Nut, m antennas. Each transmitter unit (TMTR) 254 receives and processes (e.g., transforms to analog, amplifies, filters and converts to a higher frequency) a corresponding stream of transmit symbols to generate a uplink signal. Nut, m transmitter units 254 provides Nut, m uplink signals for transmission from Nut, m antennas 252 to access point 110.
[0027] A specific number of Nup user terminals may be scheduled for simultaneous uplink transmission. Each of these user terminals performs spatial processing on its data symbol stream and transmits its set of transmit symbol streams on the uplink to the access point.
[0028] At access point 110, Nap antennas 224a to 224ap receive uplink signals from all Nup user terminals transmitting on the uplink. Each antenna 224 provides the received signal to its respective receiver unit
53 / 59P34171EN00 (RCVR) 222. Each receiver unit 222 performs complementary processing to the processing performed by the transmitter unit 254 and provides the received symbol stream. The RX spatial processor 240 performs receiver spatial processing on Nap received symbol streams from Nap receiver units 222 provides Nup of reconstructed uplink data streams. Receiver spatial processing is performed in accordance with the inverse channel correlation matrix (CCMI), minimum mean square error (MMSE), successive interference removal (SIC), or some other method. Each reproduced stream of {Sup.m} uplink data symbols is an estimate of the stream of {Sup.m} data symbols transmitted by the respective user terminal. The RX 242 data processor demodulates, deinterlaces and decodes) the data symbol stream {Sup.m} of the link processes (e.g., each restored uplink at the speed used for that stream to obtain decoded data. Decoded data for each user terminal can be provided to data 244 for storage and / or to controller 230 for further processing.
[0029] At the downlink, at access point 110, the TX data processor 210 receives traffic data from the Ndn data source 208 of user terminals scheduled for downlink transmission, control data from the controller 230 and possibly other data from the scheduling unit 234. Different types of data can be sent in different transport channels. The TX 210 data processor processes (e.g. encodes, interleaves and modulates) traffic data for each user terminal based on the speed selected for that user terminal. TX 210 data processor provides Ndn downlink symbol data streams for Ndn user terminals. TX spatial processor 220 performs spatial processing on Ndn symbol downlink data streams and provides Nap symbol streams
Transmitters for Nap antennas. Each transmitter unit (TMTR) 222 receives and processes the corresponding transmit symbol stream to generate a downlink signal. Nap transmitter 222 units provide Nap downlink signals for transmission from Nap antennas 224 to user terminals.
[0030] At each user terminal 120, Nut, m antennas 252 receives Nap downlink signals from access point 110. Each receiver unit (RCVR) 254 processes the received signal from the associated antenna 252 and provides the received symbol stream. The RX 260 spatial processor performs receiver spatial processing on the Nut.m received symbol streams from the Nut.m receiver units 254 and provides a reconstructed downlink symbol data stream {Sdp.m} for the user terminal. Receiver spatial processing is performed according to CCMI, MMSE or some other method. The RX 270 data processor processes (e.g., demodulates, deinterlaces and decodes) the recovered downlink data symbol stream to obtain decoded data for the user terminal.
[0031] In each user terminal 120, Nut.m antennas 252 receives Nap signals of the downlink from access point 110. Each receiver unit (RCVR) 254 processes the received signal from the associated antenna 252 and provides the received symbol stream. The RX 260 spatial processor performs receiver spatial processing on the Nut.m received symbol streams from the Nut.m receiver units 254 and provides a reconstructed stream of {Sdn, m} downlink data symbols for the user terminal. Spatial processing of the receiver is performed in accordance with CCMI, MMSE or some other method. The RX 270 data processor processes (e.g., demodulates, deinterlaces and decodes) the recovered downlink data symbol stream to obtain decoded data for the user terminal.
[0032] FIG. 3 illustrates various components that can be used in a 302 wireless device that can be used in a 100 system. The 302 wireless device is
53 / 59P34171EN00 pilot example of a device that can be configured to implement the various methods described herein. Wireless device 302 may be access point 110 or user terminal 120.
[0033] Wireless device 302 may include a processor 304 that controls the operation of the wireless device 302. The processor 304 may also be referred to as a central processing unit (CPU). Memory 306, which may include both read-only memory (ROM) and direct access memory (RAM), provides instructions and data to processor 304. Part of memory 306 may also include non-volatile direct access memory (NVRAM). Processor 304 typically performs logic and arithmetic operations based on program instructions stored in memory 306. Instructions in memory 306 may be executable to implement the methods described herein.
[0034] Wireless device 302 may also include a housing 308, which may include a transmitter 310 and a receiver 312 to enable data transmission and reception between wireless device 302 and a remote location. Transmitter 310 and receiver 312 can be combined into transceiver 314. A plurality of transmit antennas 316 can be connected to housing 308 and electrically connected to transmitter 314. Wireless device 302 may also include (not shown) multiple transmitters, multiple receivers, and multiple transceivers.
[0035] Wireless device 302 may also include a signal detector 318, which may be used when attempting to detect and quantify the level of signals received by the transceiver 314. The signal detector 318 may detect signals such as total energy, on a subcarrier per energy symbol, power spectral density and other signals. Wireless device
53 / 59P34171PL00
302 it may also include a digital signal processor (DSP) 320 for use in signal processing.
[0036] The various components of the wireless device 302 may be interconnected by a bus system 322, which in addition to the data bus may include a power bus, a control signal bus, and a status signal bus.
[0037] Those skilled in the art will recognize that the methods described herein can generally be used in systems using any type of multi-access schemes, such as, for example, SDMA, OFDMA, CDMA, SDMA and combinations thereof.
MU-MIMO VHT HEADER ENHANCEMENTS TO ENABLE THE TRANSMISSION MODE DETECTION [0038] Some aspects of the present invention provide methods for detecting the signal transmission mode at a receiver. For example, the transmitter can transmit signals using various standards, such as IEEE 802.11n / a / ac standards. The receiver should be able to detect the transmission mode (i.e. the standard used for transmission) of the signal so that it can correctly process the signal. In both uplink and downlink SDMA, information about the signal transmission mode can be included in the header of each frame for use in receivers.
[0039] FIG. 4A and 4B illustrate the proposed frame structures for a multiple input - multiple output (MU-MIMO) downlink very high bandwidth user (VHT) system of the present invention.
[0040] As illustrated in FIG. 4A, header fields in the frame structure such as short training field (L-STF), large according to some aspects long training field (L-LTF), signal (L-SIG), high bandwidth signal (HT-SIG1) 402 and HT-SIG2 404 are common to
53 / 59P34171EN00 all users and are therefore not subject to beamforming. Very high throughput field - short training field (VHT-STF) 408 is the first field in the frame that is subject to beam formation. In addition, the rest of the fields in the frame that are transmitted after the VHT-STF field are also subject to beamforming for specific users.
[0041] For some aspects of the present invention, the STF field may be used to adjust the automatic gain control (AGC) setting. For the station to process the VHT-STF 408 field correctly, the station must know the transmission mode or standard (e.g. IEEE 802.11n, IEEE 802.11ac or IEEE 802.11a) that is used for transmission.
[0042] Information about the signal transmission mode may be included in the very high bandwidth signal field (VHTSIG). The VHT-SIG field can be divided into two parts. For some aspects, each of the first and second portions of the VHT-SIG field may include one or more OFDM symbols.
[0043] The first part 406 of the VHT-SIG field may be common among all users and not be subject to beam forming. This part may come after the HT-SIG2 404 field in the downlink frame to notify the receiving stations about the transmission mode.
[0044] The second part 412 of the VHT-SIG field may be specific to each STA station and thus be subject to beam shaping. For some aspects, as illustrated in FIG. 4A, the second part 412 of the VHT-SIG field may be transmitted after the first long training field (LTF) for all stations. For some aspects, as illustrated in FIG. 4B, the second part 412 of the VHT-SIG field may be transmitted to the station after transmitting all of the long training fields.
[0045] FIG. 4B illustrates the proposed frame structure for a very high-bandwidth (VHT) MU-MIMO system, in accordance with some aspects of the present invention.
53 / 59P34171PL00
In this figure, most of the fields are similar to figure 4A. The only difference between Figures 4A and 4B is the location of the second part 412 of the VHT-SIG field. In Figure 4B, the second part 412 of the VHT-SIG field is transmitted to each station after all long training fields assigned to that station.
[0046] As illustrated in FIG. 4A and 4B, single spatial streams are assigned to users 1 to 4. Thus, each user receives a single LTF 410 field after receiving the VHT-STF 408 field. On the other hand, four spatial streams are assigned to user 5, thus, user 5 receives four LTF 410 fields, one corresponding to each of the spatial streams. For some aspects of the present invention, at least one LTF field may be used to estimate the channel for each spatial stream in the receiver.
[0047] In accordance with some aspects, there may be a "training sequence" in which the AP is able to obtain "signatures" for each of the stations. The AP may use these signatures to carry out the beamforming so that each station can recognize its respective second part of the VHT-SIG field.
[0048] For some aspects of the present invention, in downlink SDMA, the first part of the VHT-SIG field that is received after the VHT-LTF1 field may indicate the number of remaining LTF fields and the modulation and coding scheme (MCS) used in the transmission. In uplink SDMA, a VHT-SIG field can be received across all LTF fields to indicate the MCS scheme used for uplink transmission to the access point.
[0049] In both uplink and downlink SMAs, the first part of the VHT-SIG field is received before the field is received
VHT-STF. Thus, the receiver decodes the VHT-SIG field and detects the transmission mode (i.e., IEEE 802.11ac / a / n) before receiving the VHT53 / 59P34171PL00 field.
STF. As a result, at the beginning of the VHT-STF 406 field, the station has information about whether the transmission mode is compliant with the IEEE 802.11 ac, IEEE 802.11a or IEEE 802.11n standards.
[0050] FIG. 5 illustrates the proposed frame structure for a Very High Bandwidth (VHT) MU-MIMO system, in accordance with some aspects of the present invention. In this frame structure, as with the downlink, the first part 406 of the VHT-SIG field is transmitted after the HTSIG2 404 field. The second part 412 of the VHT-SIG field is transmitted after all LTFs are transmitted (similar to FIG. 4B). The rest of the fields in this frame structure are similar to the downlink frames illustrated in FIG. 4A and 4B.
[0051] For some aspects of the present invention, a unified frame structure for uplink and downlink can be used to enable the receiver to detect the transmission mode (i.e., IEEE 802.11n / a / ac). The unified frame structure (as shown in FIGS. 4B and 5) may include a VHT-SIG field, which is divided into two parts. The first part of the VHT-SIG field can be shared by all users, and the second part of the VHT-SIG field can be specific to each user. For some aspects, for a unified uplink-downlink frame structure, the second part of the VHT-SIG field may be transmitted over all VHTLTF fields to allow uniformity between the uplink and the downlink.
[0052] For some aspects of the present invention, in a system using a unified frame structure for both uplink and downlink, stations receiving a frame on a downlink may perform self-detection to determine if the symbol after VHT-LTF 1 is the second part VHT-SIG fields or LTF fields. For this purpose, the station may use one of the existing HT-SIG detection algorithms. Thus, no additional equipment may be required. Thanks
In detecting the second part of the VHT-SIG field, the station has information that all of the long training fields are received, and is able to count the number of different LTF fields assigned to the station.
[0053] For some aspects, the first part of the VHT-SIG field may also provide receivers using the IEEE802.11ac standard with information about the transmission mode (e.g. DL-SDMA, ULSDMA or MIMO 802.11ac), bandwidth (e.g. 20/40/80 MHz) and other common parameters, such as total transmission length, limiter use or zero padding, the maximum number of LTF fields or the longest MUMIMO transmission time among all spatial streams, and other parameters. The total transmission length may already have been included in the HT-SIG field, but a separate length may be required if receivers using the IEEE 802.11n standard and receivers using the IEEE 802.11ac standard have falsified different durations.
[0054] After receiving the first part of the VHT-SIG field, the station may detect the transmission mode by using the first part of the VHT-SIG field. For some aspects, a station may use a special constellation (e.g., rotated binary phase shift keying (BPSK)) for mode detection. For example, transmission mode information may be transmitted on an orthogonal axis relative to the constellation used in VHT-SIG field transmission.
[0055] FIG. 6 depicts example operations 600 for transmitting a frame suitable for detecting a mode, in accordance with some aspects of the present invention. At step 602, the transmitter generates a frame structure including a signal field (SIG). At step 604, the transmitter transmits the first part of the SIG field in the frame structure, the first part being common to many users, and the frame structure transmission mode is detected based on the first part of the SIG field. At 606, the transmitter can transmit the STF field to multiple users
Using multi-user beamforming, wherein the STF field is transmitted after the first part of the field
SIG.
[0056] At step 608, the transmitter can transmit LTF fields in a frame structure using beam shaping for multiple users. At step 610, the transmitter transmits a second portion of the SIG field in the frame structure, the second portion being specific to each of the plurality of users. The second part of the SIG field may be subject to beam shaping to each user and may be transmitted over LTF fields.
[0057] For some aspects, the second part of the SIG field may include an MCS scheme and a transmission length for each user. In addition, the second part of the SIG field can be transmitted by using the MCS scheme with a single spatial stream.
[0058] FIG. 7 depicts example operations 700 for detecting the transmission mode of a received signal at a receiver, in accordance with some aspects of the present invention. At 702, the receiver receives the first portion of the SIG field in the frame structure, the SIG field comprising a first portion that is common to multiple devices and a second portion that is specific to each device. At 704, the receiver determines the transmission mode of the frame structure based on the first portion of the SIG field, wherein the transmission mode is compliant with at least one of the IEEE 802.11 ac / n / a standards. At 706, the receiver receives the remainder of the frame structure based on the transmission mode. Transmission mode may include IEEE 802.11ac / a / n standards.
[0059] In some aspects of the present invention, methods have been proposed for including information about the signal transmission mode in the frame header, so the receivers can detect the transmission mode and correctly process the received signals.
[0060] The various operations of the methods described above can be performed by any suitable means capable of
53 / 59P34171EN00 to perform the respective functions. These measures may include various component (s) and / or hardware and software module (s), including, but not limited to, a circuit, special purpose integrated circuit (ASIC) or processor.
Generally, when operations are illustrated in the figures, these operations may have corresponding corresponding means-plus-function components with similar numbering. For example, blocks
602-610 in FIG. 6 correspond to blocks 602A-610A of the system illustrated in FIG. 6A. In addition, blocks 702-706 in FIG. 7 correspond to blocks 702A-706A of the system illustrated in FIG. 7A. [0061] For some aspects, the means to include a receiver, the means to transmit the transmitter, and the means to determine the transmission mode include a system configured to determine the signal transmission mode. [0062] The various operations of the methods described above can be performed by any suitable means capable of performing operations, such as various types of component (s), systems and / or hardware and / or software module (s). In general, any operations illustrated in the figures may be performed by appropriate functional means capable of performing operations.
[0063] As used herein, the term includes many different activities. For example, it may include counting, calculating, processing, determining, testing, browsing (e.g., browsing a table, database or other data structure), checking and the like. In addition, "determining" may include receiving (e.g., receiving information), accessing (e.g. accessing data in memory) and "determining" may include analyzing, selecting, determining and the like.
[0064] The expression "at least one of A or B" as used herein is intended to include any combination of A and receiving includes determining the term "like". In addition, matching
53 / 59P34171PL00
B. In other words, "at least one of A or B" includes the following set: [A], [B] and [A, B].
[0065] Various exemplary logic blocks, modules and circuits described in connection with the present invention may be implemented or implemented using a general purpose processor, digital signal processor (DSP), special purpose integrated circuit (ASIC), directly programmable gate matrix programmable logic device
FPGA) or other (PLD), transistor circuits, any of their intended uses described here can be logical discrete combinations of functions.
with discrete gates or hardware components, or designed to perform a general processor microprocessor, but alternatively the processor can be any commercially available processor, controller, microcontroller or state machine. The processor can also be implemented as a combination of processing devices, e.g. a combination of a DSP processor and microprocessor, multiple microprocessors, one or more microprocessors in combination with a DSP core, or any other such configuration.
[0066] The steps of the method or algorithm described in connection with the present invention may be implemented directly in hardware form, in a software module executed by the processor, or in a combination thereof. The software module may be in any form of storage medium that is known in the art. Some examples of storage media that can be used include direct access memory (RAM), read-only memory (ROM), flash memory, EPROM, EEPROM, registers, hard disk, portable disk, CD-ROM and so on The software module may contain a single instruction or multiple instructions, and may be distributed over several different code segments, in different programs and on multiple storage media. The storage medium may be connected to the processor so that the processor can
Read information from the storage medium and write information to the storage medium. Alternatively, the storage medium may be integrated in the processor.
[0067] The methods described herein include one or more steps or steps to achieve the described method. Steps and / or method steps can be interchanged without departing from the scope of the claims. In other words, unless a specific order of steps or activities is specified, the order and / or use of specific steps and / or activities may be modified without departing from the scope of the claims.
[0068] The functions described can be implemented in hardware, software, firmware or any combination thereof. When implemented in software, these functions may be stored as one or more instructions on a computer readable medium. Storage media can be any of the available media that can be accessed by a computer. By way of example and not limitation, such computer-readable media may include RAM, ROM, EEPROM, CD-ROM or other optical disk memory, magnetic disk memory or other magnetic storage devices, or any other medium that may be used to transfer or store desired program code in the form of instructions or data structures and which can be accessed by a computer. The terms disc and disc as used herein include compact disc (CD), laser disc, optical disc, general purpose digital disc (DVD), floppy disk and Blu-ray disc, with discs typically playing magnetic data while discs playing optically with the help of lasers.
[0069] Thus, some aspects may include a computer program product for performing the operations described herein. For example, such
The computer program product may include a computer readable medium having instructions (and / or coded) on it, the instructions being executable by one or more processors to perform the operations described herein. For some aspects, a computer program product may contain packaging material.
[0070] The software or instructions may also be transmitted using a transmission medium. For example, if the software is transmitted from a website, server or other remote source using a coaxial cable, fiber optic cable, twisted pair of wires, digital subscriber line (DSL) or wireless technologies such as infrared, radio waves and microwaves, then the coaxial cable, fiber optic cable, twisted pair of wires, DSL digital subscriber connection or wireless technologies such as infrared, radio waves and microwaves are included in the definition of transmission medium. [0071] Furthermore, it should be noted that modules and / or other suitable means for implementing the methods and methods described herein can be downloaded and / or otherwise obtained by the user terminal and / or base station as appropriate. For example, such a device may be connected to a server to facilitate the transfer of funds to perform the methods described herein. Alternatively, the various methods described herein may be provided through memory means (e.g., RAM, ROM, physical storage media such as a compact disk (CD) or floppy disk, etc.) such that the user terminal and / or base station can receive different ways after connecting or supplying storage media to the device. In addition, any other suitable method may be used to provide the device with the methods and methods described herein.
[0072] It should be understood that the claims are not limited to the exact configuration and components illustrated above. Various modifications, changes and variations can be made in the system, operation and details of the methods and devices described above without departing from the scope of the claims.
[0073] The methods provided herein may be used in various applications. For some aspects, the methods described herein may be included in an access point station, access terminal, mobile handset, or other type of wireless device with processing logic and elements for implementing the methods described herein.
[0074] Although the above description relates to aspects of the present invention, other and additional aspects of the invention may be developed without departing from its basic scope, while the scope of the invention is defined by the following claims.
Qualcomm Incorporated Proxy:
53 / 59P34171PL00
Contents5
29 members in 14 offices
Priority claims14
| Document | Office | Kind | Date |
|---|---|---|---|
| 23345109 | United States of America | P | |
| 23345109 | United States of America | P | |
| 23492709 | United States of America | P | |
| 23492709 | United States of America | P | |
| 84805810 | United States of America | A | |
| 84805810 | United States of America | A | |
| 10747745 | European Patent Office (EPO) | A | |
| 2010045389 | United States of America | W | |
| 2010045389 | United States of America | W | |
| EP20100747745 | – | – | – |
| US20090233451P | – | – | – |
| US20090234927P | – | – | – |
| US20100848058 | – | – | – |
| WO2010US45389 | – | – | – |
Members29
| Document | Office | Kind | |
|---|---|---|---|
| WO2011019968A1 | World Intellectual Property Organization (WIPO) | A1 | |
| TW201119307A | Taiwan Province of China | A | |
| US2011188482A1 | United States of America | A1 | |
| KR20120049911A | Republic of Korea | A | |
| CN102474492A | China | A | |
| EP2465238A1 | European Patent Office (EPO) | A1 | |
| JP2013502173A | Japan | A | |
| HK1170869A1 | Hong Kong, China | A1 | |
| KR101330115B1 | Republic of Korea | B1 | |
| EP2465238B1 | European Patent Office (EPO) | B1 | |
| ES2458924T3 | Spain | T3 | |
| DK2465238T3 | Denmark | T3 | |
| PT2465238E | Portugal | E | |
| EP2747359A1 | European Patent Office (EPO) | A1 | |
| JP2014140188A | Japan | A | |
| PL2465238T3This record | Poland | T3 | |
| TWI458303B | Taiwan Province of China | B | |
| US2015078368A1 | United States of America | A1 | |
| JP5815770B2 | Japan | B2 | |
| CN102474492B | China | B | |
| BR112012002958A2 | Brazil | A2 | |
| EP2747359B1 | European Patent Office (EPO) | B1 | |
| CN105721369A | China | A | |
| ES2577119T3 | Spain | T3 | |
| HUE026956T2 | Hungary | T2 | |
| US9503931B2 | United States of America | B2 | |
| US9503932B2 | United States of America | B2 | |
| CN105721369B | China | B | |
| BR112012002958B1 | Brazil | B1 |
Numbers
- Publication, DOCDB
- 2465238
- Publication, EPODOC
- PL2465238T
- Application
- 747745
- Application, DOCDB
- 10747745
- Application, EPODOC
- PL20100747745T
Titles2
- English
- Enhancements to the MU-MIMO VHT preamble to enable transmission mode detection
- Polish
- Ulepszenia nagłówka MU-MIMO VHT w celu umożliwienia wykrywania trybu transmisji
Classification
- CPC, 9
- H04L27/0012
- H04L27/2613
- H04L27/345
- H04W72/12
- H04L27/26136
- H04B7/0452
- H04L25/0202
- H04W84/12
- H04W28/065
- IPC, 5
- H04L27 26
- H04L1 00
- H04L27 00
- H04L27 34
- H04W72 12