Feedback signaling error detection and checking in MIMO wireless communication systems

[0001] This notification relates to wireless communication.

BACKGROUND [0002] The objective of the LTE (Long Term Evolution) Third Generation Partnership Project (3GPP) - (Third Generation Partnership Project) is to develop new technology, new architecture and new methods for setting and configuring wireless communication systems in to improve spectral efficiency, reduce delays and better use of radio resources, to lead to faster user experiences and richer applications and services for users at a lower cost.

[0003] Wireless communication systems typically require feedback signaling to allow uplink and downlink communication. For example, the Hybrid Automatic Retransmission Request (HARQ) automatic hybrid request requires feedback / no acknowledgment (ACK / NACK) - (Acknowledge / Non-acknowledge). Adaptive Modulation and Coding (AMC) requires channel feedback quality (CQI) feedback from the receiver. Multiple-Input Multiple-Output multiple-input systems or pre-coding requires rank (rank) and / or Precoding Matrix Index (PMI) ratio from the receiver. Usually, this kind of feedback signaling is protected by coding and signaling it is not possible to control or detect errors. However, effective signaling is necessary for the dedicated terrestrial radio access network (E-UTRAN) - (Terrestrial Radio Access Network) of the universal mobile telecommunications system (UMTS) (Universal Mobile Telecomunication System). Adding the possibility of error checking (EC) - (Error Check) and error detection to signaling control with feedback means that more advanced applications are possible. The possibility of error checking (EC) - (Error Check) and error detection can enable advanced signaling schemes, extended MIMO performance, reduced system overhead, and increased system bandwidth.

[0004] An example of an application that may require the ability to detect and control errors for feedback control feedback is to validate the precoding information. The pre-coding information validation is used to inform the WTRU about the precoding information that is used in the e-Node-B node so that the effective channel perceived by the WTRU that contains the precoding effects can be played back by the WTRU. This is required for accurate data detection for MIMO systems using pre-coding, beamforming or the like. [0005] The Wireless Transmit Receive Unit (WTRU) may provide back the Precoding Matrix Index (PMI) indicator or the antenna weight to the Base Station (BS) (Base Station) or node of the type. e Node-B (eNB type node). In order to inform the WTRU unit of the pre-coding matrix used in the eNB type node, the eNB type node may send the validation message to the unit

WTRU. Each matrix, which the WTRU unit signals as feedback to the eNB type node can be marked by the PMI_j1 indicator, PMI_j2 indicator ... PMI_jN indicator, where N is an integer value equal to the total number of matrices. An eNB type node can send a validation message containing information about N PMI indices marked by the PMI_k1 indicator, PMI_k2 indicator ... PMI_kN indicator to the WTRU unit.

[0006] Each PMI may be represented by L bits. The L value depends on the antenna configuration and the MIMO Multiple-Input Multiple-Output code book (Multiple-Input Multiple-Output) code.

[0007] Communication resources can be assigned to a WTRU. The resource block (RB) - (Resource Block) consists of M subcarriers, for example M = 12, where M is a positive integer. A resource block group (RBG) (Resource Block Group) or subband may include N_RB blocks RB, where N_RB can be, for example, 2, 4, 5, 6, 10, 25 or more. The width of the system bandwidth may have one or more RBGs or subbands depending on the size of the bandwidth and the N_RB value falling on the RBG group or the subband.

[0008] The WTRU may provide one PMI indicator for each RBG group or subband that is configured with it. The term RBG group and subband may be used interchangeably. N RBG groups, where N <N_RBG, can be configured to or selected by the WTRU for the feedback and reporting purpose. If the N RBGs or subbands are configured to or selected by the WTRU, the WTRU then returns the N PMIs back to the eNB type node. An eNB type node may send a validation message consisting of N PMIs back to the WTRU.

[0009] Let N_PMI be the number of bits that represents the PMI. The total number of bits for WTRU PMI indicator feedback is N x N_PMI. The maximum number of bits for WTRU PMI feedback is N_RBG x N_PMI bits per feedback case.

When a straightforward precoding precoding scheme is used, the maximum number of bits for the PMI indicator validation message is N_RBG x N_PMI bits per validation message.

[0010] Table 1 shows the number of bits for WTRU signaling PMI feedback and signaling with the assumption that N_PMI = 5 bits. The numbers are set for 5, 10 and 20 MHz bandwidth. The second row, N_RB, is the number of RBs per RBG group or subband that are in the range of 2 to 100 for 20 MHz. The third line, N_RBG per band, is the number of RBGs or subbands per 5, 10 or 20 MHz. The N_RBG value ranges from one to fifty. The fourth row is the total number of bits used for feedback signaling of the WTRU's PMI indicator for the feedback case. This is for the feedback of frequency-selective pre-coding or multiple PMI feedback.

Table 1. Maximum number of bits for PMI feedback and PMI verification

<td rowspan="2"></td><td colspan="2" rowspan="2">5 MHz pick</td><td colspan="2" rowspan="2">(300 various)</td><td colspan="5">10 MHz (600</td><td colspan="2" rowspan="2">(1200</td><td colspan="4" rowspan="2">2 0MHz lifts)</td>

<td colspan="3">lifting</td><td colspan="2">ch)</td>

<td>N RB per RBG</td><td>2</td><td>5</td><td>10</td><td>25</td><td>2</td><td>5</td><td>10</td><td>25</td><td>50</td><td>2</td><td>5</td><td>10</td><td>25</td><td>50</td><td>100</td>

<td>N RBG per band</td><td>13</td><td>5</td><td>3</td><td>1</td><td>25</td><td>10</td><td>5</td><td>2</td><td>1</td><td>50</td><td>20</td><td>10</td><td>4</td><td>2</td><td>1</td>

<td>Max # bits for PMI feedback due to feedback</td><td>65</td><td>25</td><td>15</td><td>5</td><td>125</td><td>50</td><td>25</td><td>10</td><td>5</td><td>250</td><td>100</td><td>50</td><td>20</td><td>10</td><td>5</td>

<td>Max # bits for PMI signaling per message</td><td>65</td><td>25</td><td>15</td><td>5</td><td>125</td><td>50</td><td>25</td><td>10</td><td>5</td><td>250</td><td>100</td><td>50</td><td>20</td><td>10</td><td>5</td>

<td></td><td colspan="15">Let's assume 12 subcarriers per RB. N_RB: Number of resource blocks. N_RBG: Number of frequency groups RB. N_PMI: Number of bits to represent PMI. Maximum number of bits for the PMI feedback of the unit WTRU = N_RBG x N_PMI bits. The maximum number of bits for the check message correctness of the node type eNB = N RBG x N PMI bits.</td>

[0011] The PMI feedback and PMI checking may require over 250 bits per feedback case and per validation message, as shown in the Table above.

[0012] The feedback error significantly reduces the link and system performance. It would be desirable that the coupling bits secured with the channel error control). Moreover, knowing whether there is an error in the feedback signal, the performance of the system is improved, as is bandwidth efficiency, because erroneous feedback information can be avoided.

Moreover, knowing whether there is an error in the feedback signaling, it is possible to use advanced feedback, they were (e.g., coding signal schemes or applications, such as schemes for confirming pre-coding and indications.) Confirmation of precoding can be sent to confirm correctness of signaling feedback if there is no error in the feedback signaling.

[0013] A single bit or a sequence of bits may be used to confirm the precoding and may be sufficient for some applications.

The use of advanced signaling such as checking the correctness of pre-coding using acknowledgment significantly reduces signaling overhead. Therefore, it is desirable to control and detect errors.

[0014] Document US-2006/0209980-A1 describes a method for transmitting data in a MIMO system. The base station performs scheduling based on feedback information received from multiple terminals. The scheduling includes determining the best terminal for each transmit antenna based on the feedback information, calculating the sum amount from the feedback information, deciding on the precoding matrix and terminals for each transmit antenna, maximizing the sum amount; and performing transmissions with a strong matrix of precoding and terminals.

[0015] EP-1628415-A1 describes a mobile radio system, where a base station with multiple antennas uses at least two downlink paths in at least two of these antennas for transmitting a user equipment signal. Each downlink path has a complex channel factor. The feedback path is used to return information about the composite scale from the user equipment to the base station. Error detection mechanisms can be used in the feedback path.

SUMMARY OF THE INVENTION [0016] A method and apparatus is provided for controlling, detecting and preventing feedback signaling errors in a wireless communication system. The feedback signaling may include a Channel Quality Index (CQI), Pre-coding Matrix Index (PMI) - (Precoding Matrix Index), rank (rank) and / or confirmation / no acknowledgment (ACK / NACK) - (Acknowledge / Non-Acknowledge). The disclosure includes a Wireless Transmit Receive Unit (WTRU) executing a method that includes providing a PMI indicator (s), generating an error check bit (s) (EC) - (Error Check), encoding the bit (s) of the indicator (indicators) PMI and EC error checking, and transmission of the encoded bit (s) of the PMI indicator (s) and EC error checking. This method can be applied to other feedback information, such as CQI, rank (rank), ACK / NACK, and the like.

BRIEF DESCRIPTION OF THE DRAWINGS [0017] A more detailed understanding may be made on the basis of the following description, presented as an example in connection with the accompanying drawings, in which:

Figure 1 shows a wireless communication system comprising a plurality of WTRUs and an eNB type node;

Figure 2 shows a functional block diagram of a WTRU and an eNB node of the wireless communication system of Figure 1;

Figure 3 is a block diagram of PMI feedback feedback with control and error correction according to one embodiment;

Figure 4 is a block diagram of PMI feedback feedback with control and error correction in accordance with another embodiment;

Figure 5 is a block diagram of PMI feedback feedback with control and error correction according to an alternative embodiment;

Figure 6 is a block diagram of PMI feedback feedback with control and error correction in accordance with another alternative embodiment; Figure 7 is a block diagram of PMI feedback feedback with control and error correction according to yet another alternative embodiment;

Figure 8 is a block diagram of PMI feedback feedback with control and error correction according to yet another alternative embodiment;

Figure 9 is a block diagram of the PMI feedback and CQI indicator with error correction and control in accordance with yet another alternative embodiment;

Figure 10 is a block diagram of the PMI feedback and CQI indicator with error correction and control in accordance with yet another alternative embodiment;

Figure 11 is a block diagram of the PMI feedback indicator, CQI and ACK / NACK indicator with control and error correction according to yet another embodiment; and

Figure 12 is a block diagram of the PMI feedback indicator, CQI and ACK / NACK indicator with control and error correction according to yet another embodiment.

DETAILED DESCRIPTION [0018] In further references, the term "wireless transmitting / receiving unit (WTRU)" - (Wireless Transmit / Receive Unit) includes user equipment (UE) - (User Equipment), a mobile station, a fixed or mobile subscriber unit, pager, mobile phone, personal digital assistant (PDA) - (Personal Digital Assistant), a computer or any other type of user equipment capable of operating in a wireless environment, but is not limited to said devices. In further references, the term &amp; quot; base station &amp; quot; includes a Node-B, site controller, access point (AP) (Access Point) or any other type of interface device capable of operating the wireless environment, but is not limited to said devices.

[0019] Figure 1 shows a wireless communication system 100 comprising a plurality of WTRUs 110 and an eNB node 120. As shown in Figure 1, the WTRUs 110 are in communication with the eNB 120 type node. Though, three WTRUs 110 and one eNB 120 are shown in Figure 1, it should be noted that any combination of wireless and wired devices may be included in the wireless communication system 100.

[0020] Figure 2 shows a functional block diagram

200 WTRU 110 units and an eNB 120 node in the wireless communication system 100 of Figure 1. As shown in

Figure 2, the WTRU 110 is in communication with the eNB 120 node. The WTRU 110 is configured to transmit the feedback signals and control signals to the eNB 120 type node. The WTRU is also configured to receive and transmit feedback signals and control signals. from and to the eNB type node. Both the eNB type node and the WTRU are configured to process signals that are modulated and encoded.

[0021] In addition to components that can be found in a typical WTRU unit, the WTRU 110 includes a processor 215, a receiver 216, a transmitter 217, and an antenna 218. A receiver 216 and a transmitter 217 communicate with a processor 215. An antenna 218 is in communication both with receiver 216 and transmitter 217 to facilitate the transmission and reception of wireless data.

In addition, the components that can be found in a typical eNB node, the eNB 120 node includes a processor 225, a receiver 226, a transmitter 227, and an antenna 228. A receiver 226 and a transmitter 227 communicate with a processor 225. The antenna 228 is in communication with both the receiver 226 and the transmitter 227 to facilitate the transmission and reception of wireless data.

[0023] The WTRU may provide a feedback signal (e.g., feedback PMI) to the eNB type node. Error check bits (EC) - (Error Check) (eg, Cyclic Redundancy Check) can be connected to a feedback signal (eg, PMI feedback). Both feedback bits ( eg, PMI) and EC error checking may be coded before transmission The feedback signal may include a PMI, CQI, rank, ACK / NACK or other type of feedback signal When this disclosure relates to a bit the PMI index, the CQI bit, the EC error bit, and the like, a specialist in a given field may consider that the PMI feedback, CQI indicator feedback and error correction and control can be, and in most cases are multiple bits. Although, feedback signals such as PMI or CQI are used as examples of other types of feedback signals, they can also be used. [0024] Different types of channels may be used to transmit and transfer a feedback signal. For example, both control type channels and data type channels can be used to transfer a feedback signal. An example of a control type channel is the physical uplink control channel (PUCCH) - (Physical Uplink Control Channel). An example of a data type channel is a physical shared uplink channel (PUSCH) - (Physical Uplink Shared Channel). and in most cases are multiple bits. Although, feedback signals such as PMI or CQI are used as examples of other types of feedback signals, they can also be used. [0024] Different types of channels may be used to transmit and transfer a feedback signal. For example, both control type channels and data type channels can be used to transfer a feedback signal. An example of a control type channel is the physical uplink control channel (PUCCH) - (Physical Uplink Control Channel). An example of a data type channel is a physical shared uplink channel (PUSCH) - (Physical Uplink Shared Channel). and in most cases are multiple bits. Although, feedback signals such as PMI or CQI are used as examples of other types of feedback signals, they can also be used. [0024] Different types of channels may be used to transmit and transfer a feedback signal. For example, both control type channels and data type channels can be used to transfer a feedback signal. An example of a control type channel is the physical uplink control channel (PUCCH) - (Physical Uplink Control Channel). An example of a data type channel is a physical shared uplink channel (PUSCH) - (Physical Uplink Shared Channel). such as the PMI or CQI indicator are used as examples of other types of feedback signals, they can also be used. [0024] Different types of channels may be used to transmit and transfer a feedback signal. For example, both control type channels and data type channels can be used to transfer a feedback signal. An example of a control type channel is the physical uplink control channel (PUCCH) - (Physical Uplink Control Channel). An example of a data type channel is a physical shared uplink channel (PUSCH) - (Physical Uplink Shared Channel). such as the PMI or CQI indicator are used as examples of other types of feedback signals, they can also be used. [0024] Different types of channels may be used to transmit and transfer a feedback signal. For example, both control type channels and data type channels can be used to transfer a feedback signal. An example of a control type channel is the physical uplink control channel (PUCCH) - (Physical Uplink Control Channel). An example of a data type channel is a physical shared uplink channel (PUSCH) - (Physical Uplink Shared Channel). [0024] Different types of channels may be used to transmit and transfer a feedback signal. For example, both control type channels and data type channels can be used to transfer a feedback signal. An example of a control type channel is the physical uplink control channel (PUCCH) - (Physical Uplink Control Channel). An example of a data type channel is a physical shared uplink channel (PUSCH) - (Physical Uplink Shared Channel). [0024] Different types of channels may be used to transmit and transfer a feedback signal. For example, both control type channels and data type channels can be used to transfer a feedback signal. An example of a control type channel is the physical uplink control channel (PUCCH) - (Physical Uplink Control Channel). An example of a data type channel is a physical shared uplink channel (PUSCH) - (Physical Uplink Shared Channel).

However, one of ordinary skill in the art would appreciate that the method and apparatus provided herein are independent of channel selection.

[0025] The PMI and EC error checking bits may be coded together, with or without data bits. Both data type channels and control type channels can be used to transmit feedback bits and EC error checking. For example, a data type channel (e.g., a physical uplink shared channel (PUSCH) - (Physical Uplink Shared Channel)) can be used to transmit PMI bits and EC error checking. The control type channel (e.g., physical uplink control channel (PUCCH) - (Physical Uplink Control Channel)) can also be used to transmit PMI bits and EC error checking.

[0026] Alternatively, the PMI and EC error checking bits may be encoded with the first coding scheme and the data bits may be encoded with the second coding scheme. Each of the coding schemes may be different. For example, convolutional encoding or Reed-Muller encoding may be used for the feedback signal and while the turbo coding is used for the data type signal. Alternatively, the coding schemes may be the same but with different parameters and settings to address different requirements of the error rate for the feedback signal and the data type signal. The data type channel (e.g., PUSCH channel) can be used to transmit PMI bits and EC error checking. Control type channel (e.g.,

[0027] The PMI bits and EC error checking can be separately encoded for each group if the grouping is used for feedback feedback.

[0028] All PMI bits and / or EC error checking can be delivered back to the loupes reported at the same time. For example, all PMI and / or EC error bits can be reported in the same transmission time interval (TTI) - (Transmission Time Interval). Alternatively, the feedback bits and error control bits can be reported at different times.

For example, the PMI bits and / or EC error checking can be divided into groups and reported in different TTI bands.

[0029] Control and error detection methods, such as cyclic redundancy check (CRC) - (Cyclic Redundancy Check), for example, can be used. If the CRC is used, it may be, for example, 24-bit CRC or 16-bit CRC. The CRC length can be varied, and the actual length used may depend on the choice of the model. [0030] The CRC bits may be coupled to signals of the feedback type and transmitted on the data type channel to carry bit-bits of feedback signals and CRC bits. The feedback signals can be, for example, PMI, CQI, rank or ACK / NACK. The data type channel may be, for example, a PUSCH channel. The data type channel has a large capacity and can accommodate a relatively large number of bits. Therefore, the CRC may be, e.g. 24-bit CRC, 16-bit CRC or some other CRC length. A long CRC can be used, and it is advantageous because it provides better error control. While this may add additional overhead due to the addition of CRC bits, the PUSCH channel may have bandwidth to support more bits. Using a data channel, such as the PUSCH channel, it allows the transmission of feedback signals, such as PMI, CQI, rank (rank) and ACK / NACK in one TTI. Therefore, a feedback signal with a long CRC may be implemented, which provides better error control capabilities. [0031] Alternatively, the CRC bits may be connected to feedback signals and transmitted on the control type channel. The cyclic redundancy CRC can be 24-bit CRC, 16-bit CRC or other CRC length. Usually,

In order to transmit CRC bits and feedback signals, the transmission can be split and transmitted repeatedly. The PMI feedback signal can be separated and transmitted in multiple TTI intervals. For example, one PMI may be transmitted in each TTI interval until all feedback signals are transmitted. The CQI or other feedback signals can be handled in a similar manner. [0032] The PMI, CQI and / or other feedback signals can be sent separately at different times or in different TTI intervals. In general, a control type channel (e.g., PUCCH) may not carry a large number of bits each time, and if there is a large number of feedback bits that need to be sent, the feedback bits can be divided or separated into groups. Each group can be reported, one at a time. Each feedback case may include a single PMI, CQI, a different feedback signal, or a combination of feedback signals. The cyclic CRC redundancy check may be provided back or transmitted at the same time (in the same TTI range) as a PMI or CQI indicator. Alternatively, the CRC may be delivered back or transmitted separately from the PMI or CQI. That is, cyclic redundancy CRC can be transmitted at different times or in different TTI intervals from times or TTI intervals such that a PMI or CQI indicator is transmitted. The cyclic CRC redundancy check can also be divided into segments or groups, each CRC segment may be sent or delivered back with the same time or a feedback signal in the same TTI interval. Each CRC segment can also be transmitted at different times or different TTI ranges.

[0033] The use of the CRC attached to the feedback signal may refer to a single feedback signal, such as one PMI and / or one CQI. Such a single feedback scheme can be used when selective frequency-independent feedback is used or wideband feedback (one feedback per entire bandwidth or per entire configured bandwidth).

[0034] Other methods of control or error detection, such as parity check (including parity check of a single bit) or block parity check, for example, can also be used. The disclosure in this document is not limited to any one particular error control scheme as would be recognized by a person skilled in the art.

[0035] Coding schemes such as convolutional coding, Reed-Solomon or Reed-Muller encoding, for example, can be used. Other coding schemes, for example, turbo coding and low density parity check (LDPC) code, may also be considered. If the feedback is sent via a data type channel (e.g., a physical uplink shared channel (PUSCH) - (Physical Uplink Shared Channel)), convolutional or block encoding may be appropriate because The data type channel (e.g., PUSCH channel) allows the transmission of a large number of bits. The Reed-Muller or Reed-Solomon coding may also be appropriate due to the moderate number of bits that are encoded by these coding schemes.

[0036] Figure 3 is a block diagram of the PMI feedback feedback indicator with error correction and control according to one embodiment. Many PMIs configured as PMI_1 302, PMI_2 304, indicators from PMI_3 306 to PMI_N-1 308 and PMI_N 310 are shown in Figure 3. The EC error checking errors 312 are connected to the PMI signal 316. The EC error checking errors 312 can be CRC bits with 24-bit length, 20-bit length or 16-bit length. Other CRC lengths may also be used. The PMI bits (302-310) and the EC error checking bits 312 are encoded by the channel coding function 314 prior to transmission. Channel coding can be performed jointly for all PMIs and EC errors. Commonly coded PMIs and EC error checking can be transmitted at the same time or in the same TTI range. Commonly coded PMIs and EC error checking can be transmitted at different times or in different TTI intervals. Alternatively, the channel coding can be performed separately for each PMI and EC error or for the PMI and EC error group. The EC error checking bits can be divided into segments, and each EC error bit segment can be a separately encoded and transmitted channel. Alternatively, the channel coding can be performed separately for each PMI and EC error or for the PMI and EC error group. The EC error checking bits can be divided into segments, and each EC error bit segment can be a separately encoded and transmitted channel. Alternatively, the channel coding can be performed separately for each PMI and EC error or for the PMI and EC error group. The EC error checking bits can be divided into segments, and each EC error bit segment can be a separately encoded and transmitted channel.

[0037] For example, if they are an integer "N" of PMIs, each PMI may be 4 bits, and each EC error check may be 24 bits, using, for example, a 24 bit CRC. The total number of bits is 4N + 24 bits. The total number of bits can be coded together using channel coding (e.g., convolutional coding). The encoded bits can be sent or delivered back at one time in one TTI interval. The total number of coded bits can also be sent or delivered back in several different times or different TTI intervals. For example, the encoded bits can be a transmitted integer "M" times in M ​​different TTI intervals. Each TTI interval can transmit (4N + 24) / M original information and CRC bits. (4N + 24) / M of original information and CRC bits in each TTI interval may include PMI and / or CRC bits. If the TTI range contains a combination of PMI and CRC bits, then 4N / M of PMI and 24 / M bits of CRC may be included in one TTI. If M = N, the 4 bits of the PMI and the fractional part of the bits of the CRC can be transmitted in one TTI. [0038] Alternatively, a 24-bit CRC may be divided into 6 segments, each with 4 bits, which are the same number of bits in the PMI indicator. Each PMI and each CRC segment can be separately or jointly coded and transmitted in the TTI range. then 4N / M bits of the PMI indicator and 24 / M bits of CRC can be included in one TTI interval. If M = N, the 4 bits of the PMI and the fractional part of the bits of the CRC can be transmitted in one TTI. [0038] Alternatively, a 24-bit CRC may be divided into 6 segments, each with 4 bits, which are the same number of bits in the PMI indicator. Each PMI and each CRC segment can be separately or jointly coded and transmitted in the TTI range. then 4N / M bits of the PMI indicator and 24 / M bits of CRC can be included in one TTI interval. If M = N, the 4 bits of the PMI and the fractional part of the bits of the CRC can be transmitted in one TTI. [0038] Alternatively, a 24-bit CRC may be divided into 6 segments, each with 4 bits, which are the same number of bits in the PMI indicator. Each PMI and each CRC segment can be separately or jointly coded and transmitted in the TTI range.

[0039] The EC error checking errors 312 can be, for example, CRC. The channel coding function 314 can be, for example, convolutional coding. Control and error detection methods, such as parity control, can also be used, and other channel coding methods, such as Reed-Muller coding or Reed-Solomon coding, can also be used, for example.

[0040] Each PMI may represent pre-coding information for a subband, RBG group, subband group, or wideband. For example, the PMI_1 may be a wideband PMI indicator ("average" precoding information for the entire band) and the PMI_2 indicator for the PMI_N indicator may be a subband of PMIs or average PMIs, each corresponding to the precoding information for the subband, and the group

RBG, or subband groups.

[0041] Similarly, the CQI and other feedback signals can be added with the possibility of error control by attaching the CRC, a coded and transmitted channel as described previously.

[0042] The PMI feedback signaling may be combined to a group with a separate error control for each PMI group of indicators. EC error checking bits can be added to each PMI group of indicators before channel coding.

[0043] Figure 4 is a block diagram of PMI feedback feedback control and error correction, according to another embodiment, where PMI_1 402, PMI_2 404 and PMI_3 406 are grouped together and a first EC error check (1) is included. 408. PMI_4 410, PMI_5 412 and PMI_6 414 are grouped together and are included with EC error checking (2) 416. PMI_N-2 418, PMI_N-1 420 and PMI_N 422 are grouped and are included with control EC errors (G) 424.

The PMI (402-406, 410-414, 418-422) and error check EC 408, 416, 424 are encoded by the channel coding function 426.

[0044] As stated above, the EC error check can be

CRC. The method of checking, detecting and correcting errors may be selected based on the total number of bits that are encoded. The EC error control may use, for example, a short or long cyclic redundancy check CRC, a single parity bit or a block parity block error. Other control, correction and error detection methods, such as advanced parity control, for example, can be used.

[0045] The channel coding function may use, for example, convolutional coding or Reed-Solomon coding. Other channel coding methods, such as block coding, turbo or LDPC encoding, for example, may also be used.

[0046] The PMIs can be divided into several groups and the PMI group of indicators can be transmitted in different transmission time intervals (TTI) - (Transmission Time Interval). Groups of PMIs can also be sent in one TTI. Each group can be reported after channel coding. This is referred to as frequency selective feedback and reporting of multiple PMIs. The CQI, rank (rank) and ACK / NACK signals can also be provided back or reported in a frequency selective manner. [0047] The PMI_1 indicator 402, the PMI_2 indicator 404, the PMI_3 indicator 406, and the EC error control (1) 408 can be reported in one TTI interval, e.g., the TTI interval (1). PMI_4 410 ratio, PMI_5 412 indicator, the PMI_6 indicator 414 and the error control EC (2) 416 may be reported in the second TTI interval, e.g. TTI (2). The PMI_N-2 418 indicator, the PMI_N-1 420 indicator, the PMI_N422 indicator and the EC error (G) 424 can be reported in another TTI interval, e.g. TTI (G).

[0048] If the detection or error checking mechanism is deactivated or if the detection and error checking capabilities are removed, there is no EC error bit attached. In this case, group 1 of PMIs (PMI_1 402, PMI_2 404, PMI_3 406) can be reported in the TTI (1), group 2 of PMIs (PMI_4 410, PMI_5 412, PMI_6 414) can be reported in the range

The TTI (2) and G group of PMI indices (PMI_N-2 418 indicator, PMI_N-1 420 index, PMI_N422 index) can be reported in the TTI (G) interval. Reporting can occur with or without EC error checking bits.

[0049] Figure 5 is a block diagram of PMI feedback feedback with error correction and control in accordance with an alternative embodiment. The EC (1) 508 error control bits are used for the PMI_1 502 indicator, the PMI_2 504 indicator and the PMI_3 index 506. The EC error bits (2) 516 are used for the PMI_4 510 indicator, the PMI_5 512 indicator and the PMI_6 514 indicator, and the error control bits EC (G) 528 are used for the indicator

PMI_N-2 522, PMI_N-1 524 indicator and PMI_N 526 indicator. The PMI pointer bits and the EC error checking bits are encoded by the channel coding function 540 prior to the transmission.

[0050] In another alternative embodiment, the PMIs may be divided into groups, and each group has an associated detection and error checking value. The feedback signaling and error control of each group are encoded separately. The encoded feedback bits and the EC error checking bits can be transmitted in the same TTI range or in different TTI intervals. Each group of PMIs, with an associated EC error check, is coded individually. [0051] Figure 6 is a block diagram of PMI feedback feedback with control and error correction in accordance with another alternative embodiment. PMIs are divided into G groups for detecting and / or correcting errors. The EC error control (1) 620 is attached to the PMI_1 602 indicator, the PMI_2 604 indicator and the indicator

PMI_3 606, EC error test (2) 622 is appended to the PMI_4 608 indicator, PMI_5 610 indicator and PMI_6 612 indicator, and EC (N) 624 error check is attached to the PMI_N-2 614 indicator, PMI_N-1 616 indicator and PMI_N indicator 618. The PMI_1 602 indicator, the PMI_2 604 indicator and the PMI_3 606 indicator and the EC (1) 620 error control are encoded by the first channel coding function 630. The PMI_4 indicator 612, the PMI_5 614 indicator and the PMI_6 616 indicator, together with the EC error control (2) 622 are encoded by the second channel coding function 640. The PMI_N-2 614 indicator, the PMI_N-1 616 indicator and the PMI_N 618 indicator, along with the EC error control (G) 824 are encoded by the G-th channel coding function 650. Control, correction and error detection methods can be selected based on the number of bits that need to be encoded. The EC error check may use, for example, a CRC, which may be, for example, 24 bit, 20 bit or 16 bit. The EC error check can also use a single parity bit or block parity check bits that have fewer bits than 16 bits. EC error checking can also use, for example, error control and detection methods, such as advanced parity check.

[0052] The channel coding functions 630, 640, 650 may use, for example, convolutional coding or Reed-Solomon coding. Other suitable channel coding, such as block coding, turbo or LDPC coding, can also be used.

[0053] The EC error checking bits may be divided into several groups, each group of EC error checking bits may be provided back or reported at the same time or at different times. For example, each group of EC error checking bits may be provided back or reported in the same or different TTI intervals.

Each group is reported by common or separate channel coding for each group.

[0054] Each group of PMIs may be reported in different TTI ranges or together in the same TTI interval. Each group is reported after separate group coding. Also, other feedback signals, such as CQI, rank (rank), and ACK / NACK, for example, can be used.

[0055] PMI_1 602, PMI_2 604, PMI_3 606 and EC error (1) 620 can be reported in the TTI (1) interval. PMI_4, PMI_5, PMI_6 and EC error (2) can be reported in the TTI (2) range, PMI_N-2, PMI_N-1, PMI_N and EC error (G) can be reported in the interval TTI let's say range

TTI (G).

[0056] If the detection or error checking mechanism is turned off or if the possibility of detecting or checking errors is removed, there may be no attached EC error checking bits. Groups of PMIs can then be reported without EC error checking bits. Group 1 of PMIs (PMI_1 402, PMI_2 404, PMI_3 406) can be reported in the TTI (1), group 2 of PMIs (PMI_4 410, PMI_5 412, PMI_6 414) can be reported in the TTI range (2) and G group of PMI indices (PMI_N-2 418 indicator, PMI_N-1 420 index, PMI_N422 index) can be reported in the TTI (G) interval. Each reporting group can have separate channel coding.

[0057] When the number of PMI groups is equal to the number of PMIs (G = N), then there is one PMI per each group of PMIs. Each indicator

PMI can be connected with EC error checking bits (eg, CRC) and encoded separately. Each PMI indicator

<td>may be</td><td colspan="2">reported</td><td colspan="2">in different times. Indicator</td><td>PMI_1 702,</td>

<td>indicator</td><td>PMI_2</td><td>704</td><td>and the PMI_N indicator</td><td>706</td><td>may be</td>

<td colspan="2">reported in</td><td colspan="2">different TTI intervals.</td><td>On</td><td>example,</td>

<td>indicator</td><td>PMI_1</td><td>702</td><td>it can be reported</td><td>in</td><td>compartment</td>

TTI (1), PMI_2 704 in the TTI (2) range and PMI_N 706 in the TTI (N) range. Feedback or reporting can occur via a control channel (e.g., physical uplink control channel (PUCCH) - (Physical Uplink Control Channel)).

Alternatively, the PMI_1 702 indicator, the PMI_2 704 index, the PMI_N 706 indicator can be reported at the same time. For example, the indicators from PMI_1 704 to PMI_N 706 can be reported in one TTI interval. This can occur via the data type channel (e.g., channel

PUSCH), due to the ability of this data type channel (e.g., PUSCH) to support more bits. Other feedback signals such as CQI, rank (rank), and ACK / NACK, for example, can be used with or instead of the PMI.

[0059] Figure 7 is a block diagram of PMI feedback feedback with control and error correction in accordance with yet another alternative embodiment.

PMIs are divided into G groups to control and detect errors, with G = N. The PMI_1 702 indicator is appended with EC (1) 712 error checking bits, the PMI_2 indicator 704 is appended with the EC error bits (2) 714 and the PMI_N indicators 706 are appended with EC (N) 716 error checking bits. Each PMI / EC pair is encoded by channel coding function 720. Corresponding control, correction and error detection schemes may be used, and may depend on the number of bits that are required to be encoded. For example, a specific EC error check may use CRC, for example,

24-bit CRC, short CRC, single parity bit or block parity check bits. The channel coding may use, for example, Reed-Solomon coding. Other appropriate control and error detection, such as long CRCs or other parity checks can be used. Other suitable channel coding, such as block coding, convolutional coding, turbo or LDPC encoding, may also be used.

[0060] By using frequency-selective reporting, the PMI_1 702 can be reported in the TTI (1) interval, the PMI_2 704 in the TTI (2) range, and the PMI_N 706 in the TTI (N) range. These PMIs can be reported via a control type channel (e.g., PUCCH). Alternatively, the indicators from PMI_1 to PMI_N can be reported in one TTI interval via a data type channel (e.g., PUSCH). Other feedback signals such as CQI, rank (rank) and ACK / NACK, for example, can be used.

[0061] Figure 8 is a block diagram of PMI feedback feedback with control and error correction in accordance with yet another alternative embodiment. Error check EC (1) 812 can be used for the PMI_1 indicator 802, error check EC (2) 814 can be used for the PMI_2 indicator (804) and the error check EC (N) 816 can be used for the PMI_N (806) indicator. The PMIs and EC error checks are encoded either separately or together in the channel coding function 820.

[0062] The PMI_1 index 802 can be reported in the TTI interval (1), the PMI_2 index 804 can be reported in the TTI interval (2) and the PMI (N) 806 indicator can be reported in the TTI (N) interval. The PMI_1 index 802, the PMI_2 index 804 and the PMI_N 806 indicator can be separately encoded and reported in different or the same TTI intervals. Alternatively, PMI_1 802, PMI_2 804 and PMI_N 806 can be co-coded, split, and reported in different TTI intervals. Moreover, the PMI_1 802 index, the PMI_2 804 index and the PMI_N 806 indicator can be co-coded and reported in the same TTI interval. Alternatively, the PMI_1 802 indicator, the PMI_2 804 indicator and the PMI_N 806 indicator can be separately encoded with different protection schemes and reported in the same TTI interval.

[0063] Figures 3 to 8 show error checking, encoding and feedback for the PMI, and show a single type of feedback signal. The CQI and other types of feedback signals can be substituted for the PMI.

[0064] Figures 9 to 12 show error checking, coding, transmission and feedback for more than one type of feedback signal. Figures 9 to 12 are discussed in more detail below.

[0065] The PMI feedback and other types of control signaling can be separately controlled for errors with the same or different error control, and then encoded together. For example, the first type of feedback signal, which may be a PMI indicator, may be combined with a first EC error control, which may be a CRC, such as 24-bit CRC. A second type of feedback signal that can be an indicator

CQI, can be included with the same EC error control.

In another example, a first type of feedback signal, which may be a PMI indicator, may be included with an EC error check, which may be a CRC, such as a 24 bit CRC. A second type of feedback signal may be coupled with a second EC error check, which may be a 16-bit CRC.

[0067] Generally, different control and / or error correction can be used for different types of feedback signals or different feedback signals of the same type. The choice which control and / or error correction can use may include a design decision for fault tolerance compared to the overhead. A longer CRC can give more protection, but it also creates more bits. Therefore, if one type of feedback signal is more important than another type of feedback signal, a stronger control and / or error correction capability can be provided to a more important type of feedback signal. Similarly for a feedback signal of the same type, if one feedback signal or a group of feedback signals is more important than another feedback signal or a group of feedback signals, a stronger control and / or error correction capability can be provided to a more important feedback signal or group of feedback signals. [0068] Referring again to the examples above, if the first feedback signal, which may be a PMI indicator, is more important than the second feedback signal, which may be a CQI indicator, then a longer CRC with a higher control and error detection capability may be used for PMI, and a shorter CRC with lower control and error detection capability can be used for the indicator a stronger control and / or error correction capability can be provided for a more important feedback signal or group of feedback signals. [0068] Referring again to the examples above, if the first feedback signal, which may be a PMI indicator, is more important than the second feedback signal, which may be a CQI indicator, then a longer CRC with a higher control and error detection capability may be used for PMI, and a shorter CRC with lower control and error detection capability can be used for the indicator a stronger control and / or error correction capability can be provided for a more important feedback signal or group of feedback signals. [0068] Referring again to the examples above, if the first feedback signal, which may be a PMI indicator, is more important than the second feedback signal, which may be a CQI indicator, then a longer CRC with a higher control and error detection capability may be used for PMI, and a shorter CRC with lower control and error detection capability can be used for the indicator

CQI.

[0069] By using different possibilities of control and / or error correction in relation to the feedback signals they can protect the feedback signal that is important, optimize the link performance and minimize signaling overhead.

[0070] Figure 9 is a block diagram of PMI feedback feedback control and error correction as well as channel quality indicator (CQI) feedback with control and error correction, in accordance with yet another alternative embodiment. The first EC 930 error check (e.g., CRC) is included in the PMI_1 902 indicator, the PMI_2904 indicator, the indicators from PMI_3 906 to PMI_N 908. The second EC940 error check is included in the CQI-1 912 to

The PMI signal 910 with the attached EC error check and the CQI signal 920 are encoded together in a channel coding function 950 to generate a single transmission signal.

[0071] In Figure 9, the first EC 930 error check and the second EC940 error check may be the same. This would give the same control and protection against errors for each feedback signal.

[0072] Alternatively, the first EC 930 error check and the second EC940 error check may be different. If the PMI feedback is more important than the system performance than the CQI feedback, the first EC930 error check may be more robust. For example, the first EC error check may be a 24-bit CRC, and the second EC error check may be a 16-bit CRC.

(e.g., CRC)

CQI-M 914 [0073] PMI feedback signals can be "broadband"

consist of a "broadband" PMI "narrowband" PMI indicator, a "subband" of the PMI and / or an average PMI. Similarly, the CQI feedback signals may consist of a CQI, "narrowband"

CQI, sub-band of CQI and / or average CQI. Also, similar to the embodiments involving single feedback, as shown in Figures 3 to 8, the EC error checking bits and the feedback bits can be transmitted in one TTI interval, or they can be split into multiple TTI intervals. More specifically, data type channels (e.g., PUSCH) can be used to transmit feedback bits and EC error checking bits in one TTI interval, since the data type channel is able to handle a larger number of bits per TTI interval.

[0074] Also, the coding used for the feedback bits and the EC error checking bits may be the same with the same or different weights, or it may be different. One skilled in the art would recognize that there are many possible combinations of coding, transmission and error checking.

[0075] Figure 10 shows a block diagram of 1000 PMI feedback and CQI indicator, in accordance with yet another embodiment. Feedback signals can be combined with error control bits together and encoded together.

they contain indicators from PMI_1 1002 to be input to the 1020 EC error addition / insertion function together with signals that contain indicators from

CQI_1 1012 to CQI_M 1014. Signals are processed by

Signals that

PMI_N 1004 are the EC error checking function 1020 and a single output signal is input to channel coding function 1030 prior to transmission.

[0076] Control signaling other than the CQI may also be used, including rank (rank) and

ACK / NACK.

[0077] Figure 11 shows a block diagram of PIB feedback feedback control with error correction, CQI feedback control and error correction, and ACK / NACK feedback according to yet another embodiment. The first error check EC 1110 is appended to the indicators PMI_1 1102 to PMI_N 1104. A second error check EC 1120 is appended to the indicators CQI_1 1112 to CQI_M 1114. The PMI signal 1106 and the CQI signal 1116 are input to the channel coding function 1140 with the signal 1130 ACK / NACK.

[0078] The ACK / NACK feedback signal 1130 can be replaced with a rank signal in Figure 12. Alternatively, a rank signal can be added to Figure 12.

[0079] Figure 12 shows a block diagram 1200 of PMI feedback and CQI feedback feedback with ACK / NACK feedback in accordance with yet another embodiment. The CQI, PMI and ACK / NACK indicators can be coded together, but separately controlled for errors. PMI signal 1202 including indicators from PMI_1 1204 to PMI_N 1206, C12I signal 1212 including indicators from CQI_1 1214 to CQI_M 1216 and 1220 ACK / NACK signal are input into the 1230 EC Attachment / Insertion function. A single output signal is processed by channel coding function 1240 and transmitted. One EC error check (e.g., CRC) is appended to the combined signal before encoding and transmission.

[0080] The ACK / NACK feedback signal 1220 may be replaced by a rank (rank) feedback signal in Figure 12. Alternatively, a rank signal may be added to Figure 12.

[0081] The PMI, CQI and ACK / NACK signals may have different control and / or protection against errors. For example, the PMI may have the highest error control and / or error protection, while the CQI may have lower error checking and / or protection against errors. The PMI, CQI and ACK / NACK indicators may have different control and / or protection against errors, using different control schemes and / or error coding or using the same control scheme and / or error coding. Different weights can be used in the PMI indicator, CQI indicator and ACK / NACK signals. Different error checking and / or error protection can be achieved by using different control schemes and / or error coding, or by using the same error control and / or coding scheme, but with different valid weights on different feedback signals by the use of non-uniform control and / or coding schemes and protection against errors. This may be applicable to other feedback signaling, such as rank (rank), for example.

[0082] Similarly, the PMI feedback signals may consist of a "wideband" PMI, a "narrowband" PMI, a "subband" of the PMI and / or an average PMI. Similarly, the CQI feedback signals may consist of a "broadband"

indicator

CQI, "narrowband"

CQI, sub-band of CQI and / or average CQI.

[0083] The methods or flow charts provided herein may be implemented in a computer program, software or firmware implemented on a computer-readable storage medium for execution by a general-purpose computer or processor. Examples of computer-readable storage media include read-only memory (ROM) - (ReadOnly Memory), random access memory (RAM) (Random-Access Memory), registry, cache memory, solid-state memory devices, magnetic media such as internal hard drives and removable drives, magneto-optical media and optical media such as CD-ROMs, and universal digital disks (DVDs) (Digital Versatile Disks).

Suitable processors include, for example, a general purpose processor, a special purpose processor, a traditional processor, a digital signal processor (DSP) - (Digital Signal Processor), multiple microprocessors, one or more microprocessors in conjunction with a DSP core, a controller, a microcontroller , Application Integrated Integrated Circuits (ASICs), Direct Programmable Gate Arrays (FPGAs) (Field Programmable Gate Array), and other types of integrated circuits (IC) - (Integrated Circuits) and / or state machines. [0085] The processor in conjunction with the software may be used to implement a radio transceiver for use in a wireless transmit receiver unit (WTRU), user equipment (UE) - (User Equipment), terminal, base station, wireless frequency vibrating, television, radio network controller (RNC) - (Radio Network Controller), or any host computer. The WTRU unit can be used in conjunction with modules, implemented in computer hardware and / or software such as a camera, video camera module, videophone, speaker phone, loudspeaker, microphone, transceiver, headset, keyboard, module

Bluetooth®, frequency modulated radio unit (FM) - (Frequency Modulated), liquid crystal display unit (LCD) - (Liquid Crystal Display) or display unit with organic light emitting diodes (OLED) - (Organic Light-Emitting Diode), digital player music, multimedia player, video game player module, web browser and / or any wireless local area network (WLAN) module - (Wireless Local Area Network) or ultra wideband (UWB) - (Ultra Wide Band).

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EP 2 557 715 B1