CN108599819B - Feedback method indicated by precoding matrix, receiver and transmitter - Google Patents

Abstract

The present invention provides a feedback method for precoding matrix indication, a receiving end and a transmitting end. The method includes: the receiving end selects a precoding matrix W from a codebook based on a reference signal, wherein,

The θ ₁ and the θ ₂ respectively represent the phase difference of the weighted values of the signals transmitted by the adjacent two antennas in the first antenna group and the second antenna group at the transmitting end for the same transmission layer, and the

represents the phase difference between the first antenna group and the second antenna group for the same transmission layer transmit signal weights and

M is a positive integer, n is a non-negative integer smaller than M, at least one precoding matrix in the codebook has different θ ₁ and θ ₂ , and the first antenna group and the second antenna group belong to the same A multi-antenna system; the receiving end sends a precoding matrix indication PMI to the transmitting end. In this way, the weak correlation of the antennas can be guaranteed, and the precision of precoding can be effectively improved, thereby reducing the performance loss and improving the throughput of the system.

Description

Feedback method indicated by precoding matrix, receiver and transmitter

technical field

The embodiments of the present invention relate to the field of wireless communication, and more particularly, to a feedback method for a precoding matrix indication, a receiving end, and a transmitting end.

Background technique

Through transmit precoding technology and receive combining technology, a multiple input multiple output (Multiple Input Multiple Output, MIMO) wireless communication system can obtain diversity and array gain. The system utilizing precoding can be expressed as

是预编码矩阵，s是发射的符号矢量，n是测量噪声。where y is the received signal vector, H is the channel matrix,

is the precoding matrix, s is the transmitted symbol vector, and n is the measurement noise.

Optimal precoding usually requires the transmitter to fully know Channel State Information (CSI). A commonly used method is that the user equipment (User Equipment, UE) quantifies the instantaneous CSI and reports it to the base station, where the user equipment includes a mobile station (Mobile Station, MS), a relay (Relay), a mobile phone (Mobile Telephone), a mobile phone ( handset) and portable equipment (portable equipment), etc., the base station includes Node B (NodeB) base station (Base station, BS), Access Point (Access Point), Transmission Point (Transmission Point, TP), Evolved Node B (Evolved Node B) , eNB) or relay (Relay) and so on. The CSI information reported by the existing Long Term Evolution (Long Term Evolution, LTE) system includes Rank Indicator (Rank Indicator, RI), Precoding Matrix Indicator (Precoding Matrix Indicator, PMI) and Channel Quality Indicator (Channel Quality Indicator, CQI) information, etc., Wherein, RI and PMI respectively indicate the number of used transmission layers and precoding matrix. The set of precoding matrices used is usually called a codebook, and each precoding matrix in it is a codeword in the codebook.

The codebook design used in the existing LTE system is based on the strong correlation between antennas. However, as the distance between the two antennas in the same polarization direction increases, the correlation between the antennas gradually weakens, and the phase differences of the antenna elements in the codebook based on the strong correlation between the antennas remain consistent. Therefore, the existing codebook design cannot be well matched when applied to the antenna configuration with a large distance, which leads to the reduction of the precoding accuracy performed by the base station according to the PMI information fed back by the UE, resulting in a large performance loss and a reduction in the system throughput. quantity.

SUMMARY OF THE INVENTION

The embodiments of the present invention provide a feedback method for precoding matrix indication, a receiving end and a transmitting end, which can improve the precision of precoding, thereby reducing performance loss and improving system throughput.

矩阵X₁是根据θ₁确定的，矩阵X₂是根据θ₂和

确定的，所述θ₁表示发射端第一天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，所述θ₂表示发射端第二天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，所述

表示所述第一天线组和所述第二天线组针对同一传输层发射信号加权值的相位差且所述

所述M为正整数，所述n为小于所述M的非负整数，在所述码本中至少有一个预编码矩阵的θ₁和θ₂不相同，所述第一天线组和所述第二天线组属于同一个多天线系统；所述接收端向所述发射端发送预编码矩阵指示PMI，以便所述发射端根据所述PMI确定所述W。In a first aspect, a method for feeding back a precoding matrix indication is provided, the method includes: a receiving end selects a precoding matrix W from a codebook based on a reference signal, wherein the

Matrix X ₁ is determined according to θ ₁ and matrix X ₂ is determined according to θ ₂ and

It is determined that the θ ₁ represents the phase difference between the two adjacent antennas in the first antenna group at the transmitting end with respect to the weighted value of the transmitted signal at the same transmission layer, and the θ ₂ represents the two adjacent antennas in the second antenna group at the transmitting end. The phase difference of the weighted value of the signal transmitted by the antenna for the same transmission layer, the

represents the phase difference between the first antenna group and the second antenna group for the same transmission layer transmit signal weights and the

The M is a positive integer, the n is a non-negative integer smaller than the M, the θ ₁ and θ ₂ of at least one precoding matrix in the codebook are different, and the first antenna group and the The second antenna group belongs to the same multi-antenna system; the receiving end sends a precoding matrix indication PMI to the transmitting end, so that the transmitting end determines the W according to the PMI.

With reference to the first aspect, in an implementation manner of the first aspect, the receiving end determines a rank indication based on the reference signal, where the rank indication corresponds to the number of useful transmission layers; the receiving end, based on the reference signal, determines from Selecting the precoding matrix W from the codebook includes: the receiving end selects the W corresponding to the rank indication from the codebook based on the reference signal.

In combination with the first aspect and any one of the above-mentioned implementations, in another implementation of the first aspect,

或When the rank indication is 1, the

or

When the rank indication is 2, the

Wherein, the α and the β are both constants.

With reference to the first aspect and any one of the above-mentioned implementations, in another implementation of the first aspect, before the receiving end selects the precoding matrix W from the codebook based on the reference signal, the The method further includes: the receiving end receives the reference signal sent by the transmitting end; wherein the reference signal includes at least one of the following: channel state information reference signal CSI RS, demodulation reference signal DM RS, cell-specific reference signal the reference signal CRS.

矩阵X₁是根据θ₁确定的，矩阵X₂是根据θ₂和

确定的，所述θ₁表示发射端第一天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，所述θ₂表示发射端第二天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，所述

表示所述第一天线组和所述第二天线组针对同一传输层发射信号加权值的相位差且所述

所述M为正整数，所述n为小于所述M的非负整数，在所述码本中至少有一个预编码矩阵的θ₁和θ₂不相同，所述第一天线组和所述第二天线组属于同一个多天线系统。A second aspect provides a method for receiving a precoding matrix indication, the method comprising: a transmitter receiving a precoding matrix indication PMI sent by a receiver; and the transmitter determining the receiver according to the precoding matrix indication PMI; The precoding matrix W selected from the codebook based on the reference signal, where the

Matrix X ₁ is determined according to θ ₁ and matrix X ₂ is determined according to θ ₂ and

It is determined that the θ ₁ represents the phase difference between the two adjacent antennas in the first antenna group at the transmitting end with respect to the weighted value of the transmitted signal at the same transmission layer, and the θ ₂ represents the two adjacent antennas in the second antenna group at the transmitting end. The phase difference of the weighted value of the signal transmitted by the antenna for the same transmission layer, the

represents the phase difference between the first antenna group and the second antenna group for the same transmission layer transmit signal weights and the

The M is a positive integer, the n is a non-negative integer smaller than the M, the θ ₁ and θ ₂ of at least one precoding matrix in the codebook are different, and the first antenna group and the The second antenna group belongs to the same multi-antenna system.

With reference to the second aspect, in an implementation manner of the second aspect, the W corresponds to a rank indication, and the rank indication corresponds to the number of useful transmission layers.

In combination with the second aspect and any one of the above-mentioned implementations, in another implementation of the second aspect,

When the rank indication is 1, the

When the rank indication is 2, the

Wherein, the α and the β are both constants.

With reference to the second aspect and any one of the foregoing implementations, in another implementation of the second aspect, before the transmitting end receives the precoding matrix indication PMI sent by the receiving end, the method further It includes: the transmitting end sends the reference signal to the receiving end, so that the receiving end selects a precoding matrix W from the codebook based on the reference signal; wherein the reference signal includes at least one of the following: Channel state information reference signal CSI RS, demodulation reference signal DM RS, cell-specific reference signal CRS.

矩阵X₁是根据θ₁确定的，矩阵X₂是根据θ₂和

确定的，所述θ₁表示发射端第一天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，所述θ₂表示发射端第二天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，所述

表示所述第一天线组和所述第二天线组针对同一传输层发射信号加权值的相位差且所述

所述M为正整数，所述n为小于所述M的非负整数，在所述码本中至少有一个预编码矩阵的θ₁和θ₂不相同，所述第一天线组和所述第二天线组属于同一个多天线系统；发送单元，用于向所述发射端发送预编码矩阵指示PMI，以便所述发射端根据所述PMI确定所述W。In a third aspect, a receiving end is provided, the receiving end includes: a selection unit, configured to select a precoding matrix W from a codebook based on a reference signal, wherein the

Matrix X ₁ is determined according to θ ₁ and matrix X ₂ is determined according to θ ₂ and

It is determined that the θ ₁ represents the phase difference between the two adjacent antennas in the first antenna group at the transmitting end with respect to the weighted value of the transmitted signal at the same transmission layer, and the θ ₂ represents the two adjacent antennas in the second antenna group at the transmitting end. The phase difference of the weighted value of the signal transmitted by the antenna for the same transmission layer, the

represents the phase difference between the first antenna group and the second antenna group for the same transmission layer transmit signal weights and the

The M is a positive integer, the n is a non-negative integer smaller than the M, the θ ₁ and θ ₂ of at least one precoding matrix in the codebook are different, and the first antenna group and the The second antenna group belongs to the same multi-antenna system; the sending unit is configured to send a precoding matrix indication PMI to the transmitting end, so that the transmitting end determines the W according to the PMI.

With reference to the third aspect, in an implementation manner of the third aspect, the receiving end further includes a determination unit configured to determine a rank indication based on the reference signal, where the rank indication corresponds to a useful transmission The number of layers; the selecting unit is specifically configured to: select the precoding matrix W corresponding to the rank indication determined by the determining unit from the codebook based on the reference signal.

In combination with the third aspect and any one of the above-mentioned implementations, in another implementation of the third aspect,

When the rank indication determined by the determining unit is 1,

或selected by the selection unit

or

When the rank indication determined by the determining unit is 2,

selected by the selection unit

Wherein, the α and the β are both constants.

With reference to the third aspect and any one of the above implementation manners, in another implementation manner of the third aspect, the receiving end further includes a receiving unit, and the receiving unit is configured to receive the transmitting end The sent reference signal; wherein, the reference signal includes at least one of the following: channel state information reference signal CSI RS, demodulation reference signal DM RS, and cell-specific reference signal CRS.

矩阵X₁是根据θ₁确定的，矩阵X₂是根据θ₂和

确定的，所述θ₁表示发射端第一天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，所述θ₂表示发射端第二天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，所述

表示所述第一天线组和所述第二天线组针对同一传输层发射信号加权值的相位差且所述

所述M为正整数，所述n为小于所述M的非负整数，在所述码本中至少有一个预编码矩阵的θ₁和θ₂不相同，所述第一天线组和所述第二天线组属于同一个多天线系统。In a fourth aspect, a transmitting end is provided, the transmitting end includes: a receiving unit, configured to receive a precoding matrix indication PMI sent by the receiving end; and a determining unit, configured to, according to the precoding matrix indication received by the receiving unit The PMI determines the precoding matrix W selected by the receiver from the codebook based on the reference signal, wherein the

Matrix X ₁ is determined according to θ ₁ and matrix X ₂ is determined according to θ ₂ and

It is determined that the θ ₁ represents the phase difference between the two adjacent antennas in the first antenna group at the transmitting end with respect to the weighted value of the transmitted signal at the same transmission layer, and the θ ₂ represents the two adjacent antennas in the second antenna group at the transmitting end. The phase difference of the weighted value of the signal transmitted by the antenna for the same transmission layer, the

represents the phase difference between the first antenna group and the second antenna group for the same transmission layer transmit signal weights and the

The M is a positive integer, the n is a non-negative integer smaller than the M, the θ ₁ and θ ₂ of at least one precoding matrix in the codebook are different, and the first antenna group and the The second antenna group belongs to the same multi-antenna system.

With reference to the fourth aspect, in an implementation manner of the fourth aspect, the W corresponds to a rank indication, and the rank indication corresponds to the number of useful transmission layers.

In combination with the fourth aspect and any one of the above-mentioned implementations, in another implementation of the fourth aspect,

When the rank indication is 1, the

When the rank indication is 2, the

Wherein, the α and the β are both constants.

With reference to the fourth aspect and any one of the above-mentioned implementations, in another implementation of the fourth aspect, the transmitting end further includes a sending unit: the sending unit is configured to send the receiving end to the Send the reference signal, so that the receiving end selects a precoding matrix W from the codebook based on the reference signal; wherein, the reference signal includes at least one of the following: channel state information reference signal CSI RS, demodulation reference Signal DM RS, cell-specific reference signal CRS.

矩阵X₁是根据θ₁确定的，矩阵X₂是根据θ₂和

确定的，所述θ₁表示发射端第一天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，所述θ₂表示发射端第二天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，所述

表示所述第一天线组和所述第二天线组针对同一传输层发射信号加权值的相位差且所述

M为正整数，n为小于M的非负整数，在所述码本中至少有一个预编码矩阵的θ₁和θ₂不相同，所述第一天线组和所述第二天线组属于同一个多天线系统；发送器，用于向所述发射端发送预编码矩阵指示PMI，以便所述发射端根据所述PMI确定所述处理器选择的所述W。In a fifth aspect, a receiving end is provided, the receiving end includes: a processor for selecting a precoding matrix W from a codebook based on a reference signal, wherein the

Matrix X ₁ is determined according to θ ₁ and matrix X ₂ is determined according to θ ₂ and

It is determined that the θ ₁ represents the phase difference between the two adjacent antennas in the first antenna group at the transmitting end with respect to the weighted value of the transmitted signal at the same transmission layer, and the θ ₂ represents the two adjacent antennas in the second antenna group at the transmitting end. The phase difference of the weighted value of the signal transmitted by the antenna for the same transmission layer, the

represents the phase difference between the first antenna group and the second antenna group for the same transmission layer transmit signal weights and the

M is a positive integer, n is a non-negative integer smaller than M, at least one precoding matrix in the codebook has different θ ₁ and θ ₂ , and the first antenna group and the second antenna group belong to the same A multi-antenna system; a transmitter, configured to send a precoding matrix indication PMI to the transmitting end, so that the transmitting end determines the W selected by the processor according to the PMI.

With reference to the fifth aspect, in an implementation manner of the fifth aspect, the processor is further configured to: determine a rank indication based on the reference signal, where the rank indication corresponds to the number of useful transmission layers; the processor specifically for: selecting the W corresponding to the determined rank indication from a codebook based on a reference signal.

In conjunction with the fifth aspect and any one of the above-mentioned implementations, in another implementation of the fifth aspect,

When the rank indication determined by the processor is 1, the

或

or

When the rank indication determined by the processor is 2, the

Wherein, the α and the β are both constants.

With reference to the fifth aspect and any one of the above implementation manners, in another implementation manner of the fifth aspect, the receiving end further includes a receiver, and the receiver is configured to receive the transmitting end The sent reference signal; wherein, the reference signal includes at least one of the following: channel state information reference signal CSI RS, demodulation reference signal DM RS, and cell-specific reference signal CRS.

矩阵X₁是根据θ₁确定的，矩阵X₂是根据θ₂和

确定的，所述θ₁表示发射端第一天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，所述θ₂表示发射端第二天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，所述

表示所述第一天线组和所述第二天线组针对同一传输层发射信号加权值的相位差且所述

所述M为正整数，所述n为小于所述M的非负整数，在所述码本中至少有一个预编码矩阵的θ₁和θ₂不相同，所述第一天线组和所述第二天线组属于同一个多天线系统。In a sixth aspect, a transmitter is provided, the transmitter includes: a receiver configured to receive a precoding matrix indication PMI sent by the receiver; and a processor configured to receive the precoding matrix indication according to the receiver The PMI determines the precoding matrix W selected by the receiver from the codebook based on the reference signal, wherein the

Matrix X ₁ is determined according to θ ₁ and matrix X ₂ is determined according to θ ₂ and

It is determined that the θ ₁ represents the phase difference between the two adjacent antennas in the first antenna group at the transmitting end with respect to the weighted value of the transmitted signal at the same transmission layer, and the θ ₂ represents the two adjacent antennas in the second antenna group at the transmitting end. The phase difference of the weighted value of the signal transmitted by the antenna for the same transmission layer, the

represents the phase difference between the first antenna group and the second antenna group for the same transmission layer transmit signal weights and the

The M is a positive integer, the n is a non-negative integer smaller than the M, the θ ₁ and θ ₂ of at least one precoding matrix in the codebook are different, and the first antenna group and the The second antenna group belongs to the same multi-antenna system.

With reference to the sixth aspect, in an implementation manner of the sixth aspect, the W corresponds to a rank indication, and the rank indication corresponds to the number of useful transmission layers.

In conjunction with the sixth aspect and any one of the above-mentioned implementations, in another implementation of the sixth aspect,

When the rank indication is 1, the

When the rank indication is 2, the

Wherein, the α and the β are both constants.

With reference to the sixth aspect and any one of the above implementation manners, in another implementation manner of the sixth aspect, the transmitting end further includes a transmitter, and the transmitter is configured to send a message to the receiving end Send the reference signal, so that the receiving end selects a precoding matrix W from the codebook based on the reference signal; wherein, the reference signal includes at least one of the following: channel state information reference signal CSI RS, demodulation reference Signal DM RS, cell-specific reference signal CRS.

分别通过θ₁和θ₂表示第一天线组中的相邻两根天线之间的相位差以及第二天线组中的相邻两根天线之间的相位差。这样，可以根据天线间距情况来选择合适的预编码矩阵，保证天线的弱相关性，因此，基站基于用户设备反馈的从本发明的码本结构中选择的预编码矩阵进行预编码，有效地提高预编码的精度，从而减少性能损失，提高系统的吞吐量。Based on the above solution, the user equipment selects the precoding matrix W from the codebook based on the reference signal, wherein,

The phase difference between two adjacent antennas in the first antenna group and the phase difference between two adjacent antennas in the second antenna group are represented by θ ₁ and θ ₂ , respectively. In this way, an appropriate precoding matrix can be selected according to the antenna spacing to ensure the weak correlation of the antennas. Therefore, the base station performs precoding based on the precoding matrix selected from the codebook structure of the present invention fed back by the user equipment, which effectively improves the Precoding precision, thereby reducing performance loss and improving system throughput.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings that need to be used in the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without any creative effort.

FIG. 1 is a flowchart of a method for feeding back a precoding matrix indication according to an embodiment of the present invention.

FIG. 2 is a flowchart of a method for receiving a precoding matrix indication according to another embodiment of the present invention.

FIG. 3 is a structural block diagram of a receiving end according to an embodiment of the present invention.

FIG. 4 is a structural block diagram of a transmitter according to an embodiment of the present invention.

Figure 5 is a block diagram of an apparatus of one embodiment of the present invention.

FIG. 6 is a structural block diagram of a receiving end according to another embodiment of the present invention.

FIG. 7 is a structural block diagram of a transmitter according to another embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

It should be understood that the technical solutions of the present invention can be applied to various communication systems, such as: Global System of Mobile communication (GSM) system, Code Division Multiple Access (Code Division Multiple Access, CDMA) system, Wideband Code Division Multiple Access (WCDMA) Wideband Code Division Multiple Access, WCDMA) system, General Packet Radio Service (General Packet Radio Service, GPRS), Long Term Evolution (Long Term Evolution, LTE) system, Advanced long term evolution (Advanced long term evolution, LTE-A) system, general Mobile communication system (Universal Mobile Telecommunication System, UMTS) and so on.

It should also be understood that, in this embodiment of the present invention, user equipment (UE, User Equipment) includes but is not limited to a mobile station (MS, Mobile Station), a relay (Relay), a mobile terminal (Mobile Terminal), and a mobile phone (MobileTelephone) , mobile phone (handset) and portable equipment (portable equipment), etc., the user equipment can communicate with one or more core networks via a radio access network (RAN, Radio Access Network), for example, the user equipment can be a mobile phone (or The user equipment may also be a portable, pocket-sized, hand-held, computer-built-in or vehicle-mounted mobile device.

In this embodiment of the present invention, the base station may be a base station (Base TransceiverStation, BTS) in GSM or CDMA, a base station (NodeB, NB) in WCDMA, or an evolved base station (Evolutional Node B, eNB or e-NodeB), or relay, etc., which are not limited in the present invention.

FIG. 1 is a flowchart of a method for feeding back a precoding matrix indication according to an embodiment of the present invention. This method is executed by the receiver.

矩阵X₁是根据θ₁确定的，矩阵X₂是根据θ₂和

确定的，θ₁表示发射端第一天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，θ₂表示发射端第二天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，

表示第一天线组和第二天线组针对同一传输层发射信号加权值的相位差且

M为正整数，n为小于M的非负整数，在码本中至少有一个预编码矩阵的θ₁和θ₂不相同，第一天线组和第二天线组属于同一个多天线系统。101. The receiving end selects the precoding matrix W from the codebook based on the reference signal, wherein,

Matrix X ₁ is determined according to θ ₁ and matrix X ₂ is determined according to θ ₂ and

Determined, θ ₁ represents the phase difference between the two adjacent antennas in the first antenna group of the transmitting end for the transmission signal weighted value of the same transmission layer, and θ ₂ represents that the two adjacent antennas in the second antenna group of the transmitting end are for the same transmission The phase difference of the weighted value of the layer transmit signal,

represents the phase difference of the weighted values of the signals transmitted by the first antenna group and the second antenna group for the same transmission layer and

M is a positive integer, n is a non-negative integer smaller than M, at least one precoding matrix in the codebook has different θ ₁ and θ ₂ , and the first antenna group and the second antenna group belong to the same multi-antenna system.

102. The receiving end sends a precoding matrix indication PMI to the transmitting end, so that the transmitting end obtains the precoding matrix W according to the PMI.

A multi-antenna system refers to a system in which a transmitter (eg, a base station) and a receiver (eg, a UE) communicate through multiple antennas. Compared with a single-antenna system, multiple antennas at the transmitting end and the receiving end can form spatial diversity gain or multiplexing gain, which can effectively improve transmission reliability and system capacity. Diversity gain and multiplexing gain in a multi-antenna system can generally be obtained through a precoding method at the transmitter and a receive combining algorithm at the receiver. For example, in an LTE system, 4 antennas are used at the transmitting end, and 2 antennas are used at the receiving end.

In addition, the multi-antenna system according to the embodiment of the present invention can also be applied to the scenario of multi-point joint transmission. Multi-point joint transmission refers to the joint transmission of signals by multiple transmitters for the same user. For example, transmitter A has two antennas. The transmitter B also has two antennas, and the two transmitters perform joint transmission to the receiver at the same time. Then the signal received by the receiving end can be regarded as a signal sent by a 4-antenna base station.

θ₁和θ₂分别表示第一天线组和第二天线组中相邻两根天线针对同一传输层发射信号加权值的相位差。这样，可以根据天线间距情况来选择合适的预编码矩阵，保证天线的弱相关性，因此，发射端基于接收端反馈的从本发明的码本结构中选择的预编码矩阵进行预编码，有效地提高预编码的精度，从而减少性能损失，提高系统的吞吐量。Based on the above solution, the receiving end selects the precoding matrix W from the codebook based on the reference signal, wherein,

θ ₁ and θ ₂ respectively represent the phase difference of the weighted values of signals transmitted by two adjacent antennas in the first antenna group and the second antenna group with respect to the same transmission layer. In this way, an appropriate precoding matrix can be selected according to the antenna spacing to ensure the weak correlation of the antennas. Therefore, the transmitting end performs precoding based on the precoding matrix selected from the codebook structure of the present invention fed back by the receiving end, effectively Improve the precision of precoding, thereby reducing performance loss and improving system throughput.

For the convenience of description, the transmitting end in the following embodiments will be described by taking a base station as an example, and the receiving end will be described by taking a UE as an example. It should be understood that this is not limited in this embodiment of the present invention, the receiving end may be a base station, and the transmitting end may be is the UE.

It should be noted that, in this embodiment of the present invention, the type of the reference signal in 101 is not limited. For example, it may be a channel state information reference signal (Channel State Information Reference Signal, CSI RS), a demodulation reference signal (Demodulation RS, DM RS), or a cell-specific reference signal (Cell-specific RS, CRS). The CSI may also include A channel quality indicator (channel Quality Indicator/Index, CQI for short). It should also be noted that the UE can obtain the resource configuration of the reference signal by receiving a notification from the base station (for example, Radio Resource Control (RRC) signaling or Downlink Control Information (Downlink Control Information, DCI)) or based on the cell ID. The reference signal is obtained in the corresponding resource or subframe.

Optionally, in step 101, the receiving end may obtain a channel estimation value based on the reference signal, calculate the channel capacity or throughput or the chord distance based on the channel estimation value, etc., according to the predefined criteria of the receiving end, such as the channel capacity or the maximum throughput. The precoding matrix is selected from the codebook according to the maximization criterion or the chord distance minimization criterion.

Further, the receiving end may also determine a rank indication RI based on the reference signal, where the rank indication RI corresponds to the number of useful transmission layers. For example, the UE may obtain the RI based on the number of ports of the reference signal and the unique value of the allowable RI corresponding to the codebook subset restriction; or the UE may obtain the channel estimation value based on the reference signal, and based on the channel estimation value, for each allowable rank The RI value is indicated, and the corresponding precoding matrix is used to calculate metric values such as channel capacity or throughput; the rank indication RI that makes the metric value optimal is selected as the determined rank indication RI. In step 101, the receiving end may select a precoding matrix W corresponding to the rank indication from the codebook based on the reference signal. Specifically, the codebook subset corresponding to the rank indication may be determined from the codebook, and then the precoding matrix W may be selected from the codebook subset, and the precoding matrix W may also be directly determined by the rank indication.

Optionally, the codebook subset may be predefined, or the receiving end reports the codebook to the transmitting end, the transmitting end determines the codebook subset and notifies the receiving end; or the receiving end determines and reports the codebook subset For example, the codebook subset restriction may be notified to the UE by the base station through higher layer signaling such as RRC signaling. Optionally, in step 102, the UE may send the precoding matrix indication PMI to the base station through a physical uplink control channel (Physical Uplink Control Channel, PUCCH) or a physical uplink shared channel (Physical Uplink Shared Channel, PUSCH). It should be understood that this embodiment of the present invention does not limit this.

In addition, the precoding matrix indication PMI and the rank indication RI may be sent in the same subframe, or may be sent in different subframes.

确定的，本发明对此不作限定。It should be understood that matrix X ₁ can also be determined according to θ ₁ and other factors (such as magnitude), that is, X ₁ is determined according to at least θ ₁ ; similarly, matrix X ₂ is determined according to at least θ ₂ and

Certainly, the present invention does not limit this.

Optionally, as an embodiment, in step 101, the precoding matrix W corresponds to a rank indication, and the rank indication corresponds to the number of useful transmission layers. When the rank indication is greater than or equal to 2, θ ₁ and θ ₂ may respectively represent the phases of the weighted values of the transmit signals of two adjacent antennas in the first antenna group and the second antenna group with respect to any one of the multiple transmission layers Difference.

Specifically, in a 4-antenna scenario, when the rank indication is 1, the precoding matrix may be:

Alternatively, when the rank indication is 2, the precoding matrix can be:

和

α and β are both constants, optionally,

and

The above examples are only exemplary, and are not intended to limit the scope of the present invention. The codebook in the present invention may also be a codebook with a rank indication of other values. For the convenience of description, the codebook with a rank indication of 1 is used in the present invention. A codebook with a sum rank indication of 2 is taken as an example for description, and it should be understood that this is not limited in the present invention.

It should also be understood that the above codebook is represented in the form of a single codebook structure, of course, it can also be represented in the form of a double codebook structure, which is not limited in the present invention.

Preferably, the embodiment of the present invention is described by taking a scenario of four antennas as an example. The four antennas are divided into two antenna groups, and each group includes two antennas. It should be understood that this embodiment of the present invention is not limited to this. For example, the embodiment of the present invention may also be applied to a scenario with 8 antennas.

Specifically, in the scenario of 8 antennas, each of the two antenna groups may include 4 antennas,

When the rank indication is 1, the precoding matrix can be:

Alternatively, when the rank indication is 2, the precoding matrix can be:

For the convenience of description, the following example will take a 4-antenna scenario as an example for description.

Optionally, in an implementation manner, taking the rank indication as 1 and 2 as an example, when the rank indication is 1, the precoding matrix:

When the rank indication is 2, the precoding matrix:

in,

Y1 and Y2 are mutually independent P×1-dimensional column selection vectors, N=2 ^k , k is a non-negative integer, m is a non-negative integer less than N, and P is a positive integer less than N. That is, N is a power of 2, which can be 0, 2, 4, 8..., etc., m∈{0,1,L,N-1}, P∈{0,1,L,N- 1}.

For example, the value of k is 4, that is, N=16, m∈{0,1,L,N-1}={0,1,L,15}, P=4, Y1 and Y2 can be the following column vectors respectively one of:

和

and

Y1和Y2可以相同或不同。which is:

Y1 and Y2 may be the same or different.

即

为(5)式中矩阵X的第一列，假设

即

为(5)式中矩阵X的第二列。Assumption

which is

is the first column of matrix X in formula (5), suppose

which is

is the second column of matrix X in formula (5).

Optionally, in step 102, the receiving end may send the first precoding matrix indication PMI ₁ and the second precoding matrix indication PMI ₂ to the transmitting end, that is, the precoding matrix indication PMI includes PMI ₁ and PMI ₂ . Further, PMI ₁ and PMI ₂ are sent in the same or different time periods. Wherein, PMI ₁ is used to indicate W ₁ , and PMI ₂ is used to indicate W ₂ ¹ or W ₂ ² . In other words, PMI ₁ and PMI ₂ may have the same or different granularity in time domain or frequency domain (or based on different subframe periods or subband sizes).

Optionally, W ₁ is a matrix representing wideband channel characteristics, W ₂ ¹ and W ₂ ² are both matrices representing sub-band channel characteristics, or W ₁ is a matrix representing long-term channel characteristics, W ₂ ¹ and W ₂ ² are matrices representing short-term channel characteristics. The superscript numbers in W ₂ indicate the value of the rank. Correspondingly, the receiving end may send PMI ₁ to the transmitting end at longer time intervals, and send PMI ₂ to the transmitting end at shorter time intervals.

Of course, the receiving end can directly indicate the selected precoding matrix W through a PMI. For example, the codebook has a total of 256 precoding matrices. When the PMI sent by the receiving end is 0, it indicates to the transmitting end which of the 256 precoding matrices. The first precoding matrix, when the PMI sent by the receiving end is 1, indicates the second precoding matrix among the 256 precoding matrices to the transmitting end..., that is, the PMI values of 0-255 correspond to 256 The corresponding precoding matrix in the precoding matrix. It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the receiving end may send the precoding matrix indication PMI to the transmitting end through a physical control channel or a physical shared channel. For example, the UE may send the precoding matrix indication PMI to the base station through the physical uplink control channel or the physical uplink shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, a column vector is independently selected in the matrix X by the column selection vectors Y1 and Y2 in the embodiment of the present invention, thereby ensuring the weak correlation of the codebook corresponding to the antennas with larger spacing.

Optionally, in another implementation manner, θ ₁ and θ ₂ can be respectively taken as:

为向下取整运算符号。即N为2的幂次，可以取值为0，2，4，8……，等等，P∈{0,1,L,N-1}，i₁∈{0,1,L,N/A-1}。Among them, N=2 ^k , k is a non-negative integer, A is a positive integer that can divide N (for example, N=16, A=2), M is a positive integer less than N, i ₁ is less than (N/A- 1) is a non-negative integer, i ₂ and i ₃ are both positive integers and i ₂ and i ₃ are independent of each other,

Operator symbol for rounding down. That is, N is a power of 2, which can be 0, 2, 4, 8..., etc., P∈{0,1,L,N-1}, i ₁ ∈{0,1,L,N /A-1}.

Optionally, in step 102, the receiving end may send the third precoding matrix indication PMI ₃ and the fourth precoding matrix indication PMI ₄ to the transmitting end, that is, the precoding matrix indication PMI includes PMI ₃ and PMI ₄ . Further, PMI ₃ and PMI ₄ are sent in the same or different time periods. Wherein, PMI ₃ is used to indicate i ₁ , and PMI ₄ is used to indicate i ₂ and i ₃ . Specifically, PMI ₄ may be the jointly encoded value of i ₂ and i ₃ . The transmitter can determine i ₂ and i ₃ according to the corresponding relationship between the value of PMI ₄ and i ₂ and i ₃ . For example, the transmitter can preset the corresponding relationship between PMI ₄ and i ₂ , determine i ₂ according to the value of PMI ₄ , and then determine i ₃ according to the relationship PMI ₄ =P·i ₂ +i ₃ ; similarly, the transmitter can preset The corresponding relationship between PMI ₄ and i ₃ , i ₃ is determined by the value of PMI ₄ , and i ₂ is determined according to the relational expression PMI ₄ =P·i ₂ +i ₃ .

In other words, PMI ₃ and PMI ₄ can have different granularity in time domain or frequency domain. Of course, the receiving end may directly indicate the selected precoding matrix W through a PMI. For specific implementation manners, reference may be made to the foregoing embodiments, which will not be repeated here.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the receiving end may send the precoding matrix indication PMI to the transmitting end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, in the embodiment of the present invention, θ ₁ and θ ₂ can be independently selected by i ₂ and i ₃ respectively according to the current channel characteristics, which ensures the weak correlation of codebooks corresponding to antennas with larger spacing.

Optionally, in another implementation manner, θ ₁ and θ ₂ can also be respectively taken as:

为向下取整运算符号，mod为取模运算符号。即N为2的幂次，可以取值为0，2，4，8……，等等，P∈{0,1,L,N-1}，i₁∈{0,1,L,N/A-1}。Among them, N=2 ^k , k is a non-negative integer, A is a positive integer that can divide N, P is a positive integer less than N, i ₁ is a non-negative integer less than (N/A-1), and i ₄ is less than (PM-1) positive integer (eg P=4, M=4, i ₄ <15),

is a round-down operator, and mod is a modulo operator. That is, N is a power of 2, which can be 0, 2, 4, 8..., etc., P∈{0,1,L,N-1}, i ₁ ∈{0,1,L,N /A-1}.

Optionally, in step 102, the receiving end may send the fifth precoding matrix indication PMI ₅ and the sixth precoding matrix indication PMI ₆ to the transmitting end, that is, the precoding matrix indication PMI includes PMI ₅ and PMI ₆ . Further, PMI ₅ and PMI ₆ are sent in the same or different time periods. Wherein, PMI ₅ is used to indicate i ₁ , and PMI ₆ is used to indicate i ₄ . In other words, PMI ₅ and PMI ₆ can have different granularity in time domain or frequency domain. Of course, the receiving end may directly indicate the selected precoding matrix W through a PMI. For specific implementation manners, reference may be made to the foregoing embodiments, which will not be repeated here.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the receiving end may send the precoding matrix indication PMI to the transmitting end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, in this embodiment of the present invention, θ ₁ and θ ₂ can be determined by i ₄ according to the current channel characteristics, and θ ₁ and θ ₂ in the selected precoding matrix can be the same or different, ensuring the codebook corresponding to the antennas with larger spacing weak correlation.

Optionally, in another implementation manner, θ ₁ and θ ₂ can also be respectively taken as:

θ ₂ =θ ₁ +Δθ (11)

Among them, N=2 ^k , k is a non-negative integer, m is a non-negative integer less than N, Δθ=2πt, the absolute value of t is less than 1, for example, t is 1/8, -1/16, -1/32 , 0, 1/32, 1/16 or 1/8 etc.

In step 101, the receiving end may select the precoding matrix W from the codebook according to the selection of θ ₁ and Δθ (eg, current channel characteristics).

Similarly, in step 102, the receiving end may send two precoding matrix indications to the transmitting end, indicating θ ₁ and Δθ respectively. Further, the two precoding matrix indications may also be sent in the same or different time periods, in other words, the two precoding matrix indications may have different granularity in time domain or frequency domain. Of course, the receiving end may directly indicate the selected precoding matrix W through a PMI. For specific implementation manners, reference may be made to the foregoing embodiments, which will not be repeated here.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the receiving end may send the precoding matrix indication PMI to the transmitting end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, in the embodiment of the present invention, the phase deviation Δθ between θ ₁ and θ ₂ can be used according to the current channel characteristics, and Δθ can be specified in a limited variation range, so as to ensure the weak correlation of the codebook corresponding to the antennas with larger spacing .

Optionally, in another implementation manner, taking the rank indication as 1 and 2 as an example, when the rank indication is 1, the precoding matrix:

or,

n₁,n₂,L,n_P均为整数，可以连续取值或者非连续取值，Y、Y₁'和Y₂'均为P×1维列选择向量，N＝2^k，k为非负整数，m1为小于N的非负整数，P为小于N的正整数。即N为2的幂次，可以取值为0，2，4，8……，等等，m1∈{0,1,L,N-1}，P∈{0,1,L,N-1}。例如，k取值为4，即N＝16，m1∈{0,1,L,N-1}＝{0,1,L,15}，α为常数，θ'为实数。in,

n ₁ , n ₂ , L, n _P are all integers, which can be continuous or non-continuous. Y, Y ₁ ' and Y ₂ ' are all P×1-dimensional column selection vectors, N=2 ^k , k is Non-negative integer, m1 is a non-negative integer less than N, P is a positive integer less than N. That is, N is a power of 2, which can be 0, 2, 4, 8..., etc., m1∈{0,1,L,N-1}, P∈{0,1,L,N- 1}. For example, the value of k is 4, that is, N=16, m1∈{0,1,L,N-1}={0,1,L,15}, α is a constant, and θ' is a real number.

Optionally, P=4, Y, Y ₁ ' and Y ₂ ' can be one of the following column vectors, respectively:

和

and

which is:

Optionally, in step 102, the receiving end may send the seventh precoding matrix indication PMI ₇ and the eighth precoding matrix indication PMI ₈ to the transmitting end, that is, the precoding matrix indication PMI includes PMI ₇ and PMI ₈ . Further, PMI ₇ and PMI ₈ are sent in the same or different time periods. Wherein, PMI ₇ is used to indicate W ₃ , and PMI ₈ is used to indicate W ₄ ¹ . In other words, PMI ₇ and PMI ₈ may have the same or different granularity in time domain or frequency domain (or based on different subframe periods or subband sizes).

Optionally, W ₃ is a matrix representing a wideband channel characteristic, W ₄ ¹ is a matrix representing a sub-band channel characteristic, or W ₃ is a matrix representing a long-term channel characteristic, and W ₄ ¹ is a matrix representing a short-term channel characteristic. matrix. Correspondingly, the receiving end may send the PMI ₇ to the transmitting end at a relatively long time interval, and send the PMI ₈ to the transmitting end at a short time interval.

When the rank indication is 2, the precoding matrix:

n₁,n₂,L,n_P均为整数，可以连续取值或者非连续取值，Y₃和Y₄均为P×1维列选择向量，N＝2^k，k为非负整数，m1为小于N的非负整数，P为小于N的正整数。即N为2的幂次，可以取值为0，2，4，8……，等等，m1∈{0,1,L,N-1}，P∈{0,1,L,N-1}。例如，k取值为4，即N＝16，m1∈{0,1,L,N-1}＝{0,1,L,15}，β为常数，θ'为实数。in,

n ₁ , n ₂ , L, n _P are all integers, which can take continuous or non-continuous values, Y ₃ and Y ₄ are both P×1-dimensional column selection vectors, N=2 ^k , k is a non-negative integer, m1 is a non-negative integer less than N, and P is a positive integer less than N. That is, N is a power of 2, which can be 0, 2, 4, 8..., etc., m1∈{0,1,L,N-1}, P∈{0,1,L,N- 1}. For example, the value of k is 4, that is, N=16, m1∈{0,1,L,N-1}={0,1,L,15}, β is a constant, and θ' is a real number.

Alternatively, when the rank indication is 2, the precoding matrix may also be:

使得码本集合中任何一个预编码矩阵中的两列相互正交。In the above formula (16), θ ₁ specifically represents the phase difference of the weighted values of the signals transmitted by the adjacent two antennas in the first antenna group of the transmitting end for the first transmission layer in the two transmission layers, and θ ₂ specifically represents the transmitting end The phase difference between the two adjacent antennas in the second antenna group for the first transmission layer in the two transmission layers transmits the signal weighted value, θ ₃ indicates that the adjacent two antennas in the first antenna group at the transmitting end are for the two transmission layers. The phase difference of the weighted value of the transmitted signal of the second transmission layer in the transmission layer, and θ ₄ indicates that the adjacent two antennas in the second antenna group at the transmitting end are weighted for the transmission signal of the second transmission layer of the two transmission layers The phase difference of the value. And, D, Y ₃ , Y ₄ in the above formula (16) and

Two columns in any precoding matrix in the codebook set are orthogonal to each other.

Wherein, when the rank is 2, Y ₃ and Y ₄ may be the same or different, which is not limited in this embodiment of the present invention.

θ’可以是正数且不为2π的整数倍，还可以是正数且不为2π的整数倍，还可以是负数且不为2π的整数倍。例如，

或者

l为正整数且不为N的整数倍。It should be pointed out that θ can take any real number, and the value of θ' is not limited in this embodiment of the present invention. For example, the value of θ' can be an integer multiple of 0 or 2π, for example,

θ' may be a positive number and not an integer multiple of 2π, a positive number and not an integer multiple of 2π, or a negative number and not an integer multiple of 2π. E.g,

or

l is a positive integer and not an integer multiple of N.

Optionally, P=4, Y ₃ and Y ₄ can each be one of the following column vectors:

和

and

which is:

Optionally, in step 102, the receiving end may send the ninth precoding matrix indication PMI ₉ and the tenth precoding matrix indication PMI ₁₀ to the transmitting end, that is, the precoding matrix indication PMI includes PMI ₉ and PMI ₁₀ . Further, PMI ₉ and PMI ₁₀ are sent in the same or different time periods. Wherein, PMI ₉ is used to indicate W ₃ , and PMI ₁₀ is used to indicate W ₄ ² . In other words, PMI ₉ and PMI ₁₀ may have the same or different granularity in time domain or frequency domain (or based on different subframe periods or subband sizes).

Optionally, W ₃ is a matrix representing the wideband channel characteristics, and W ₄ ² is a matrix representing the sub-band channel characteristics, or W ₃ is a matrix representing the long-term channel characteristics, and W ₄ ² is the short-term channel characteristics. matrix. Correspondingly, the receiving end may send the PMI ₉ to the transmitting end at a longer time interval, and send the PMI ₁₀ to the transmitting end at a shorter time interval.

Of course, the receiving end may directly indicate the selected precoding matrix W through a PMI. For specific implementation manners, reference may be made to the foregoing embodiments, which will not be repeated here.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the receiving end may send the precoding matrix indication PMI to the transmitting end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, through the selection of θ' in the embodiment of the present invention, the weak correlation of the codebook corresponding to the antennas with larger spacing is guaranteed.

It should be pointed out that other equivalent matrices to represent the above codebook (or precoding matrix) all fall within the scope of the present invention. For example, a precoding matrix after row or column permutation of the precoding matrix W in the embodiment of the present invention also falls within the scope of the present invention, for example, different antenna numbers will correspondingly lead to row permutation of the precoding matrix.

FIG. 2 is a flowchart of a precoding method according to another embodiment of the present invention. The method of FIG. 2 is performed by the transmitting end, and corresponds to the method of FIG. 1 , and thus the overlapping description with the embodiment of FIG. 1 will be appropriately omitted.

201. The transmitting end receives the precoding matrix indication PMI sent by the receiving end.

矩阵X₁是根据θ₁确定的，矩阵X₂是根据θ₂和

确定的，θ₁表示发射端第一天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，θ₂表示发射端第二天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，

表示第一天线组和第二天线组针对同一传输层发射信号加权值的相位差且

M为正整数，n为小于M的非负整数，在码本中至少有一个预编码矩阵的θ₁和θ₂不相同，第一天线组和第二天线组属于同一个多天线系统。202, the transmitting end determines the precoding matrix W selected by the receiving end from the codebook based on the reference signal according to the precoding matrix indication PMI, wherein,

Matrix X ₁ is determined according to θ ₁ and matrix X ₂ is determined according to θ ₂ and

Determined, θ ₁ represents the phase difference between the two adjacent antennas in the first antenna group of the transmitting end for the transmission signal weighted value of the same transmission layer, and θ ₂ represents that the two adjacent antennas in the second antenna group of the transmitting end are for the same transmission The phase difference of the weighted value of the layer transmit signal,

represents the phase difference of the weighted values of the signals transmitted by the first antenna group and the second antenna group for the same transmission layer and

M is a positive integer, n is a non-negative integer smaller than M, at least one precoding matrix in the codebook has different θ ₁ and θ ₂ , and the first antenna group and the second antenna group belong to the same multi-antenna system.

θ₁和θ₂分别表示第一天线组和第二天线组中相邻两根天线针对同一传输层发射信号加权值的相位差。这样，可以根据天线间距情况来选择合适的预编码矩阵，保证天线的弱相关性，因此，发射端基于接收端反馈的从本发明的码本结构中选择的预编码矩阵进行预编码，有效地提高预编码的精度，从而减少性能损失，提高系统的吞吐量。Based on the above solution, the transmitting end receives the precoding matrix indication PMI sent by the receiving end, and determines according to the precoding matrix indication PMI that the receiving end selects the precoding matrix W from the codebook based on the reference signal, wherein,

θ ₁ and θ ₂ respectively represent the phase difference of the weighted values of signals transmitted by two adjacent antennas in the first antenna group and the second antenna group with respect to the same transmission layer. In this way, an appropriate precoding matrix can be selected according to the antenna spacing to ensure the weak correlation of the antennas. Therefore, the transmitting end performs precoding based on the precoding matrix selected from the codebook structure of the present invention fed back by the receiving end, effectively Improve the precision of precoding, thereby reducing performance loss and improving system throughput.

Optionally, the reference signal in step 202 may be CSI RS, DM RS or CRS, and the CSI may further include a channel quality indicator CQI. It should also be noted that the UE may obtain the resource configuration of the reference signal by receiving a notification from the base station (eg, RRC signaling or DCI) or based on the cell ID, and obtain the reference signal in the corresponding resource or subframe.

Optionally, in step 201, the transmitting end may receive the precoding matrix indication PMI sent by the receiving end through a physical control channel or a physical shared channel. For example, the base station may receive the precoding matrix indication PMI sent by the UE through PUCCH or PUSCH. It should be understood that this embodiment of the present invention does not limit this.

Preferably, the embodiment of the present invention applies a scenario of four antennas, and the four antennas are divided into two antenna groups, and each group includes two antennas. It should be understood that this embodiment of the present invention is not limited to this. For example, the embodiment of the present invention may also be applied to an 8-antenna scenario, and the precoding matrix form in the 8-antenna scenario can be referred to above, which will not be repeated here. For the convenience of description, the following example will take a 4-antenna scenario as an example for description.

确定的，本发明对此不作限定。It should be understood that matrix X ₁ can also be determined based on θ ₁ and other factors such as magnitude, ie X ₁ is determined based on at least θ ₁ ; similarly, matrix X ₂ is determined based on at least θ ₂ and

Certainly, the present invention does not limit this.

Optionally, as an embodiment, the precoding matrix W corresponds to a rank indication, and the rank indication corresponds to the number of useful transmission layers, and the rank indication can be determined by the receiving end. Specifically, in the scenario of 4 antennas, the precoding matrix with the rank indication of 1 may be the above formula (1); or the precoding matrix with the rank indication of 2 may be the above formula (2).

The above examples are only exemplary, and are not intended to limit the scope of the present invention. The codebook in the present invention may also be a codebook with a rank indication of other values. For the convenience of description, the codebook with a rank indication of 1 is used in the present invention. A codebook with a sum rank indication of 2 is taken as an example for description, and it should be understood that this is not limited in the present invention.

It should also be understood that the above codebook is represented in the form of a single codebook structure, of course, it can also be represented in the form of a double codebook structure, which is not limited in the present invention.

Optionally, in an implementation manner, in step 202, taking the rank indication as 1 and 2 as an example, when the rank indication is 1, the precoding matrix determined by the transmitting end may be the above formula (3); or, When the rank indication is 2, the precoding matrix determined by the transmitting end may be the above formula (4).

For example, the value of k is 4, that is, N=16, m∈{0,1,L,N-1}={0,1,L,15}, P=4, Y1 and Y2 can be the following column vectors respectively one of:

和

and

Y1和Y2可以相同或不同。which is:

Y1 and Y2 may be the same or different.

即

为上述(5)式中矩阵X的第一列，假设

即

为上述(5)式中矩阵X的第二列。Assumption

which is

is the first column of the matrix X in the above formula (5), suppose

which is

is the second column of the matrix X in the above formula (5).

Optionally, in step 201, the transmitting end receives the first precoding matrix indication PMI ₁ and the second precoding matrix indication PMI ₂ sent by the receiving end, and the precoding matrix indication PMI includes PMI ₁ and PMI ₂ . Further, the PMI ₁ and PMI ₂ sent by the receiving end are received in the same or different time periods. In other words, PMI ₁ and PMI ₂ may have the same or different granularity in time domain or frequency domain (or based on different subframe periods or subband sizes). In step 202, the transmitter determines the W _{1 selected by the receiver from the codebook based on the reference signal according to PMI 1 ,} and determines W ₂ ¹ or W ₂ ² selected by the UE from the codebook according to PMI _2. The transmitter may The precoding matrix W is determined according to W ₁ and W ₂ ¹ , or the precoding matrix W is determined according to W ₁ and W ₂ ² .

Optionally, W ₁ is a matrix representing the channel characteristics of the wideband, both W ₂ ¹ and W ₂ ² are matrices representing the channel characteristics of the sub-band, and the superscript number in W ₂ represents the value of the rank; or W ₁ is a representation of the rank For the long-term channel characteristic matrix, both W ₂ ¹ and W ₂ ² are matrices representing short-term channel characteristics. Correspondingly, the transmitting end may receive the PMI ₁ sent by the receiving end at a relatively long time interval, and receive the PMI ₂ sent by the receiving end at a short time interval.

Of course, the transmitter can directly determine the selected precoding matrix W through a PMI sent by the receiver. For example, there are 256 precoding matrices in the codebook. When the PMI sent by the receiver is 0, the transmitter determines The receiving end selects the first precoding matrix in the 256 precoding matrices of the codebook. When the transmitting end receives the PMI sent by the receiving end is 1, the transmitting end determines that the receiving end selects the 256 precoding matrices of the codebook. The second precoding matrix in , ..., that is, the values 0-255 of the PMI correspond to corresponding precoding matrices in the 256 precoding matrices, respectively. It should be understood that the embodiment of the present invention does not limit the manner in which the UE indicates the precoding matrix.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the transmitting end may receive the precoding matrix indication PMI sent by the receiving end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, a column vector is independently selected in the matrix X by the column selection vectors Y1 and Y2 in the embodiment of the present invention, thereby ensuring the weak correlation of the codebook corresponding to the antennas with larger spacing.

和

其中，N＝2^k，k为非负整数，A为能整除N的正整数(例如，N＝16，A＝2)，M为小于N的正整数，i₁为小于(N/A-1)的非负整数，i₂和i₃均为正整数且i₂和i₃相互独立，

为向下取整运算符号。即N为2的幂次，可以取值为0，2，4，8……，等等，P∈{0,1,L,N-1}，i₁∈{0,1,L,N/A-1}。Optionally, in another implementation manner, θ ₁ and θ ₂ can be respectively taken as

and

Among them, N=2 ^k , k is a non-negative integer, A is a positive integer that can divide N (for example, N=16, A=2), M is a positive integer less than N, i ₁ is less than (N/A- 1) is a non-negative integer, i ₂ and i ₃ are both positive integers and i ₂ and i ₃ are independent of each other,

Operator symbol for rounding down. That is, N is a power of 2, which can be 0, 2, 4, 8..., etc., P∈{0,1,L,N-1}, i ₁ ∈{0,1,L,N /A-1}.

Optionally, in step 201, the transmitting end receives the third precoding matrix indication PMI ₃ and the fourth precoding matrix indication PMI ₄ sent by the receiving end, and further receives the PMI sent by the receiving end in the same or different time periods. ₃ and PMI ₄ . In step 202, the transmitter determines i ₁ according to PMI ₃ , and determines i ₂ and i ₃ according to PMI ₄ . Specifically, PMI ₄ may be the jointly encoded value of i ₂ and i ₃ . The transmitter can determine i ₂ and i ₃ according to the corresponding relationship between the value of PMI ₄ and i ₂ and i ₃ . For example, the transmitter can preset the corresponding relationship between PMI ₄ and i ₂ , determine i ₂ according to the value of PMI ₄ , and then determine i ₃ according to the relationship PMI ₄ =P·i ₂ +i ₃ ; similarly, the transmitter can preset The corresponding relationship between PMI ₄ and i ₃ , i ₃ is determined by the value of PMI ₄ , and i ₂ is determined according to the relational expression PMI ₄ =P·i ₂ +i ₃ .

In other words, PMI ₃ and PMI ₄ can have different granularity in time domain or frequency domain. Of course, the transmitting end may directly determine the selected precoding matrix W through a PMI sent by the receiving end. For specific implementation manners, reference may be made to the foregoing embodiments, which will not be repeated here.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the transmitting end may receive the precoding matrix indication PMI sent by the receiving end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, in the embodiment of the present invention, θ ₁ and θ ₂ can be independently selected by i ₂ and i ₃ respectively according to the current channel characteristics, which ensures the weak correlation of codebooks corresponding to antennas with larger spacing.

和

其中，N＝2^k，k为非负整数，A为能整除N的正整数，P为小于N的正整数，i₁为小于(N/A-1)的非负整数，i₄为小于(PM-1)的正整数(例如P＝4，M＝4，i₄<15)，

为向下取整运算符号，mod为取模运算符号。即N为2的幂次，可以取值为0，2，4，8……，等等，P∈{0,1,L,N-1}，i₁∈{0,1,L,N/A-1}。Optionally, in another implementation manner, θ ₁ and θ ₂ can also be respectively set as

and

Among them, N=2 ^k , k is a non-negative integer, A is a positive integer that can divide N, P is a positive integer less than N, i ₁ is a non-negative integer less than (N/A-1), and i ₄ is less than (PM-1) positive integer (eg P=4, M=4, i ₄ <15),

is a round-down operator, and mod is a modulo operator. That is, N is a power of 2, which can be 0, 2, 4, 8..., etc., P∈{0,1,L,N-1}, i ₁ ∈{0,1,L,N /A-1}.

Optionally, in step 201, the transmitting end receives the fifth precoding matrix indication PMI ₅ and the sixth precoding matrix indication PMI ₆ sent by the receiving end, and further, receives the PMI sent by the receiving end in the same or different time periods. ₅ and PMI ₆ . In step 202 , i ₁ is determined according to PMI ₅ , and i ₄ is determined according to PMI ₆ . In other words, PMI ₅ and PMI ₆ can have different granularity in time domain or frequency domain. Of course, the transmitting end may directly determine the selected precoding matrix W through a PMI sent by the receiving end. For specific implementation manners, reference may be made to the foregoing embodiments, which will not be repeated here.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the transmitting end may receive the precoding matrix indication PMI sent by the receiving end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, in this embodiment of the present invention, θ ₁ and θ ₂ can be determined by i ₄ according to the current channel characteristics, and θ ₁ and θ ₂ in the selected precoding matrix can be the same or different, ensuring the codebook corresponding to the antennas with larger spacing weak correlation.

和θ₂＝θ₁+Δθ。其中，N＝2^k，k为非负整数，m为小于N的非负整数，Vθ＝2πt，t的绝对值小于1，例如，t为1/8，-1/16、-1/32、0、1/32，1/16或1/8等。Optionally, in another implementation manner, θ ₁ and θ ₂ can also be respectively set as

and θ ₂ =θ ₁ +Δθ. Among them, N=2 ^k , k is a non-negative integer, m is a non-negative integer less than N, Vθ=2πt, the absolute value of t is less than 1, for example, t is 1/8, -1/16, -1/32 , 0, 1/32, 1/16 or 1/8 etc.

Similarly, in step 201, the transmitting end may receive two precoding matrix indications sent by the receiving end, where the two precoding matrix indications indicate θ ₁ and Δθ respectively. Further, the two precoding matrix indications sent by the receiving end may also be received in the same or different time periods, in other words, the two precoding matrix indications may have different granularity in time domain or frequency domain. The transmitter can determine the precoding matrix W through θ ₁ and Δθ; of course, the transmitter can directly determine the precoding matrix W selected by the receiver through a PMI sent by the receiver. For specific implementation manners, reference may be made to the foregoing embodiments, which will not be repeated here.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the transmitting end may receive the precoding matrix indication PMI sent by the receiving end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, in the embodiment of the present invention, the phase deviation Δθ between θ ₁ and θ ₂ can be used according to the current channel characteristics, and Δθ can be specified in a limited variation range, so as to ensure the weak correlation of the codebook corresponding to the antennas with larger spacing .

Optionally, in an implementation manner, in step 202, when the rank indication is 1, the precoding matrix determined by the transmitting end may be the above formula (12) or (13).

Similarly, in step 201, the transmitting end may receive two precoding matrix indications sent by the receiving end, the seventh precoding matrix indication PMI ₇ and the eighth precoding matrix indication PMI ₈ , the two precoding matrix indications respectively indicate PMI ₇ and PMI ₈ , further, the two precoding matrix indications sent by the receiving end may also be received in the same or different time periods, in other words, the two precoding matrix indications may have different time domains or frequencies. Domain granularity. In step 202, the transmitter determines W ₃ selected by the receiver from the codebook based on the reference signal according to PMI ₇ , and determines W ₄ ¹ selected by the UE from the codebook according to PMI _8. The transmitter can determine W 3 and W 4 according to W ₃ and W ₄ ¹ Determine the precoding matrix W.

Optionally, W ₃ is a matrix representing a wideband channel characteristic, W ₄ ¹ is a matrix representing a sub-band channel characteristic, or W ₃ is a matrix representing a long-term channel characteristic, and W ₄ ¹ is a matrix representing a short-term channel characteristic. matrix. Correspondingly, the receiving end may send the PMI ₇ to the transmitting end at a relatively long time interval, and send the PMI ₈ to the transmitting end at a short time interval.

When the rank indication is 2, the precoding matrix determined by the transmitting end may be the above formula (14) or (16).

Similarly, in step 201, the transmitting end may receive two precoding matrix indications sent by the receiving end, the ninth precoding matrix indication PMI ₉ and the tenth precoding matrix indication PMI ₁₀ , the two precoding matrix indications respectively indicate PMI ₉ and PMI ₁₀ , further, may also receive the two precoding matrix indications sent by the receiving end in the same or different time periods, in other words, the two precoding matrix indications may have different time domains or frequencies. Domain granularity. In step 202, the transmitter determines W ₃ selected by the receiver from the codebook based on the reference signal according to PMI ₉ , and determines W ₄ ² selected by the UE from the codebook according to PMI _10. The transmitter can determine W 3 and W 4 according to W ₃ and W ₄ ² Determine the precoding matrix W.

Of course, the transmitting end may directly determine the precoding matrix W selected by the receiving end through a PMI sent by the receiving end. For specific implementation manners, reference may be made to the foregoing embodiments, which will not be repeated here.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the transmitting end may receive the precoding matrix indication PMI sent by the receiving end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, through the selection of θ' in the embodiment of the present invention, the weak correlation of the codebook corresponding to the antennas with larger spacing is guaranteed.

It should be pointed out that other equivalent matrices to represent the above codebook (or precoding matrix) all fall within the scope of the present invention. For example, a precoding matrix after row or column permutation of the precoding matrix W in the embodiment of the present invention also falls within the scope of the present invention, for example, different antenna numbers will correspondingly lead to row permutation of the precoding matrix.

FIG. 3 is a structural block diagram of a receiving end according to an embodiment of the present invention. The receiving end 300 includes a selecting unit 301 and a sending unit 302 .

矩阵X₁是根据θ₁确定的，矩阵X₂是根据θ₂和

确定的，θ₁表示发射端第一天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，θ₂表示发射端第二天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，

表示第一天线组和第二天线组针对同一传输层发射信号加权值的相位差且

M为正整数，n为小于M的非负整数，在码本中至少有一个预编码矩阵的θ₁和θ₂不相同，第一天线组和第二天线组属于同一个多天线系统。A selection unit 301, configured to select a precoding matrix W from a codebook based on a reference signal, wherein,

Matrix X ₁ is determined according to θ ₁ and matrix X ₂ is determined according to θ ₂ and

Determined, θ ₁ represents the phase difference between the two adjacent antennas in the first antenna group of the transmitting end for the transmission signal weighted value of the same transmission layer, and θ ₂ represents that the two adjacent antennas in the second antenna group of the transmitting end are for the same transmission The phase difference of the weighted value of the layer transmit signal,

represents the phase difference of the weighted values of the signals transmitted by the first antenna group and the second antenna group for the same transmission layer and

M is a positive integer, n is a non-negative integer smaller than M, at least one precoding matrix in the codebook has different θ ₁ and θ ₂ , and the first antenna group and the second antenna group belong to the same multi-antenna system.

The sending unit 302 is configured to send the precoding matrix indication PMI to the transmitting end, so that the transmitting end determines the precoding matrix W selected by the selecting unit 301 according to the PMI.

A multi-antenna system refers to a system in which the transmitter and receiver communicate through multiple antennas. Compared with a single-antenna system, multiple antennas at the transmitting end and the receiving end can form spatial diversity gain or multiplexing gain, which can effectively improve transmission reliability and system capacity. Diversity gain and multiplexing gain in a multi-antenna system can generally be obtained through a precoding method at the transmitter and a receive combining algorithm at the receiver. For example, in an LTE system, 4 antennas are used at the transmitting end, and 2 antennas are used at the receiving end.

In addition, the multi-antenna system according to the embodiment of the present invention can also be applied to the scenario of multi-point joint transmission. Multi-point joint transmission refers to the joint transmission of signals by multiple transmitters for the same user. For example, transmitter A has two antennas. The transmitter B also has 2 antennas, and both transmitters perform joint transmission to the receiver at the same time. Then the signal received by the receiving end can be regarded as a signal sent by a 4-antenna base station.

θ₁和θ₂分别表示第一天线组和第二天线组中相邻两根天线针对同一传输层发射信号加权值的相位差。这样，可以根据天线间距情况来选择合适的预编码矩阵，保证天线的弱相关性，因此，发射端基于接收端反馈的从本发明的码本结构中选择的预编码矩阵进行预编码，有效地提高预编码的精度，从而减少性能损失，提高系统的吞吐量。Based on the above solution, the receiving end selects the precoding matrix W from the codebook based on the reference signal, wherein,

θ ₁ and θ ₂ respectively represent the phase difference of the weighted values of signals transmitted by two adjacent antennas in the first antenna group and the second antenna group with respect to the same transmission layer. In this way, an appropriate precoding matrix can be selected according to the antenna spacing to ensure the weak correlation of the antennas. Therefore, the transmitting end performs precoding based on the precoding matrix selected from the codebook structure of the present invention fed back by the receiving end, effectively Improve the precision of precoding, thereby reducing performance loss and improving system throughput.

In this embodiment of the present invention, the transmitting end may be a base station, and correspondingly, the receiving end may be a UE; or the transmitting end may be a UE, and correspondingly, the receiving end may be a base station. It should be understood that this embodiment of the present invention is not limited thereto.

The receiving end 300 may implement the various steps involved in the receiving end in the methods in FIGS. 1 to 2 , which will not be described in detail in order to avoid repetition.

Optionally, as an embodiment, the receiving end 300 may further include a determining unit 303 configured to determine a rank indication based on the reference signal, where the rank indication corresponds to the number of useful transmission layers. The selecting unit 301 is specifically configured to: select the precoding matrix W corresponding to the rank indication determined by the determining unit 303 from the codebook based on the reference signal.

Specifically, when the rank indication determined by the determination unit 303 is 1, the precoding matrix selected by the selection unit 301 may be the above formula (1); or, when the rank indication determined by the determination unit 303 is 2, the precoding matrix selected by the selection unit 301 The precoding matrix may be Equation (2) above.

The above examples are only exemplary, and are not intended to limit the scope of the present invention. The codebook in the present invention may also be a codebook with a rank indication of other values. For the convenience of description, the codebook with a rank indication of 1 is used in the present invention. A codebook with a sum rank indication of 2 is taken as an example for description, and it should be understood that this is not limited in the present invention.

It should also be understood that the above codebook is represented in the form of a single codebook structure, of course, it can also be represented in the form of a double codebook structure, which is not limited in the present invention.

Optionally, in an implementation manner, taking the rank indication as 1 and 2 as an example, when the rank indication determined by the determining unit 303 is 1, the precoding matrix selected by the selecting unit 301 may be the above formula (3); or , when the rank indication determined by the determining unit 303 is 2, the precoding matrix selected by the selecting unit 301 may be the above formula (4). For specific examples, reference may be made to the above, and details are not repeated here.

Optionally, W ₁ is a matrix representing the channel characteristics of the wideband, both W ₂ ¹ and W ₂ ² are matrices representing the channel characteristics of the sub-band, and the superscript number in W ₂ represents the value of the rank; or W ₁ is a representation of the rank For the long-term channel characteristic matrix, both W ₂ ¹ and W ₂ ² are matrices representing short-term channel characteristics.

Optionally, the precoding matrix indication PMI sent by the sending unit 302 may include a first precoding matrix indication PMI ₁ and a second precoding matrix indication PMI ₂ , where PMI ₁ is used to indicate W ₁ , and PMI ₂ is used to indicate W ₂ ¹ or W ₂ ² . Correspondingly, the transmitting end may receive the PMI ₁ sent by the sending unit 302 at a longer time interval, and receive the PMI ₂ sent by the sending unit 302 at a shorter time interval.

Therefore, a column vector is independently selected in the matrix X by the column selection vectors Y1 and Y2 in the embodiment of the present invention, thereby ensuring the weak correlation of the codebook corresponding to the antennas with larger spacing.

Optionally, in another implementation manner, when the rank indication determined by the determining unit 303 is 1, the precoding matrix selected by the selecting unit 301 may be the above formula (12) or (13), and the specific example may refer to the above, It will not be repeated here.

Optionally, W ₃ is a matrix representing a wideband channel characteristic, W ₄ ¹ is a matrix representing a sub-band channel characteristic, or W ₃ is a matrix representing a long-term channel characteristic, and W ₄ ¹ is a matrix representing a short-term channel characteristic. matrix.

Optionally, the precoding matrix indication PMI sent by the sending unit 302 may include a seventh precoding matrix indication PMI ₇ and an eighth precoding matrix indication PMI ₈ , where PMI ₇ is used to indicate W ₃ , and PMI ₈ is used to indicate W ₄ ¹ . In other words, PMI ₇ and PMI ₈ may have the same or different granularity in time domain or frequency domain (or based on different subframe periods or subband sizes). Correspondingly, the transmitting end may receive the PMI ₇ sent by the sending unit 302 at a longer time interval, and receive the PMI ₈ sent by the sending unit 302 at a shorter time interval.

Optionally, in another implementation manner, when the rank indication determined by the determining unit 303 is 2, the precoding matrix selected by the selecting unit 301 may be the above formula (14) or (16). For a specific example, refer to the above, It will not be repeated here.

Optionally, W ₃ is a matrix representing the wideband channel characteristics, and W ₄ ² is a matrix representing the sub-band channel characteristics, or W ₃ is a matrix representing the long-term channel characteristics, and W ₄ ² is the short-term channel characteristics. matrix.

Optionally, the precoding matrix indication PMI sent by the sending unit 302 may include a ninth precoding matrix indication PMI ₉ and a tenth precoding matrix indication PMI ₁₀ , where PMI ₉ is used to indicate W ₃ , and PMI ₁₀ is used to indicate W ₄ ² . Correspondingly, the transmitting end may receive the PMI ₉ sent by the sending unit 302 at a longer time interval, and receive the PMI ₁₀ sent by the sending unit 302 at a shorter time interval.

Therefore, through the selection of θ' in the embodiment of the present invention, the weak correlation of the codebook corresponding to the antennas with larger spacing is guaranteed.

和

其中，N＝2^k，k为非负整数，A为能整除N的正整数(例如，N＝16，A＝2)，M为小于N的正整数，i₁为小于(N/A-1)的非负整数，i₂和i₃均为正整数且i₂和i₃相互独立，

为向下取整运算符号。即N为2的幂次，可以取值为0，2，4，8……，等等，P∈{0,1,L,N-1}，i₁∈{0,1,L,N/A-1}。Optionally, in another implementation manner, θ ₁ and θ ₂ can be respectively taken as

and

Among them, N=2 ^k , k is a non-negative integer, A is a positive integer that can divide N (for example, N=16, A=2), M is a positive integer less than N, i ₁ is less than (N/A- 1) is a non-negative integer, i ₂ and i ₃ are both positive integers and i ₂ and i ₃ are independent of each other,

Operator symbol for rounding down. That is, N is a power of 2, which can be 0, 2, 4, 8..., etc., P∈{0,1,L,N-1}, i ₁ ∈{0,1,L,N /A-1}.

Optionally, the precoding matrix indication PMI sent by the sending unit 302 may include a third precoding matrix indication PMI ₃ and a fourth precoding matrix indication PMI ₄ , where PMI ₃ is used to indicate i ₁ , and PMI ₄ is used to indicate i ₂ and i ₃ , specifically, PMI ₄ may be the jointly encoded value of i ₂ and i ₃ . The transmitter can determine i ₂ and i ₃ according to the corresponding relationship between the value of PMI ₄ and i ₂ and i ₃ . For example, the transmitter can preset the corresponding relationship between PMI ₄ and i ₂ , determine i ₂ according to the value of PMI ₄ , and then determine i ₃ according to the relationship PMI ₄ =P·i ₂ +i ₃ ; similarly, the transmitter can preset The corresponding relationship between PMI ₄ and i ₃ , i ₃ is determined by the value of PMI ₄ , and i ₂ is determined according to the relational expression PMI ₄ =P·i ₂ +i ₃ .

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Therefore, in the embodiment of the present invention, θ ₁ and θ ₂ can be independently selected by i ₂ and i ₃ respectively according to the current channel characteristics, which ensures the weak correlation of codebooks corresponding to antennas with larger spacing.

和

其中，N＝2^k，k为非负整数，A为能整除N的正整数，P为小于N的正整数，i₁为小于(N/A-1)的非负整数，i₄为小于(PM-1)的正整数(例如P＝4，M＝4，i₄<15)，

为向下取整运算符号，mod为取模运算符号。即N为2的幂次，可以取值为0，2，4，8……，等等，P∈{0,1,L,N-1}，i₁∈{0,1,L,N/A-1}。Optionally, in another implementation manner, θ ₁ and θ ₂ can also be respectively set as

and

Among them, N=2 ^k , k is a non-negative integer, A is a positive integer that can divide N, P is a positive integer less than N, i ₁ is a non-negative integer less than (N/A-1), and i ₄ is less than (PM-1) positive integer (eg P=4, M=4, i ₄ <15),

is a round-down operator, and mod is a modulo operator. That is, N is a power of 2, which can be 0, 2, 4, 8..., etc., P∈{0,1,L,N-1}, i ₁ ∈{0,1,L,N /A-1}.

Optionally, the precoding matrix indication PMI sent by the sending unit 302 may include a fifth precoding matrix indication PMI ₅ and a sixth precoding matrix indication PMI ₆ , where the PMI ₅ is used to indicate i ₁ , and the PMI ₆ is used to indicate i ₄ .

和θ₂＝θ₁+Δθ。其中，N＝2^k，k为非负整数，m为小于N的非负整数，Vθ＝2πt，t的绝对值小于1，例如，t为1/8，-1/16、-1/32、0、1/32，1/16或1/8等。Optionally, in another implementation manner, θ ₁ and θ ₂ can also be respectively set as

and θ ₂ =θ ₁ +Δθ. Among them, N=2 ^k , k is a non-negative integer, m is a non-negative integer less than N, Vθ=2πt, the absolute value of t is less than 1, for example, t is 1/8, -1/16, -1/32 , 0, 1/32, 1/16 or 1/8 etc.

Therefore, in the embodiment of the present invention, the phase deviation Δθ between θ ₁ and θ ₂ can be used according to the current channel characteristics, and Δθ can be specified in a limited variation range, so as to ensure the weak correlation of the codebook corresponding to the antennas with larger spacing .

Optionally, as another embodiment, the selection unit 301 may also be configured to: perform row permutation or column permutation on the precoding matrix W according to the number of the antenna.

It should be pointed out that other equivalent matrices to represent the above codebook (or precoding matrix) all fall within the scope of the present invention. For example, a precoding matrix after row or column permutation of the precoding matrix W in the embodiment of the present invention also falls within the scope of the present invention, for example, different antenna numbers will correspondingly lead to row permutation of the precoding matrix.

Optionally, as another embodiment, the receiving end 300 may further include a receiving unit 304, and the receiving unit 304 is configured to receive the reference signal sent by the transmitting end. The determining unit 303 is specifically configured to determine the rank indication based on the reference signal received by the receiving unit 304 ; or the selecting unit 301 is specifically configured to select the precoding matrix W from the codebook based on the reference signal received by the receiving unit 304 . Wherein, the reference signal includes at least one of the following: CSI RS, DM RS, or CRS, etc.

FIG. 4 is a structural block diagram of a transmitter according to an embodiment of the present invention. The transmitting end 400 in FIG. 4 includes a receiving unit 401 and a determining unit 402 .

The receiving unit 401 is configured to receive the precoding matrix indication PMI sent by the receiving end.

矩阵X₁是根据θ₁确定的，矩阵X₂是根据θ₂和

确定的，θ₁表示发射端第一天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，θ₂表示发射端第二天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，

表示第一天线组和第二天线组针对同一传输层发射信号加权值的相位差且

M为正整数，n为小于M的非负整数，在码本中至少有一个预编码矩阵的θ₁和θ₂不相同，第一天线组和第二天线组属于同一个多天线系统。The determining unit 402 is configured to determine, according to the precoding matrix indication PMI received by the receiving unit 401, the precoding matrix W selected by the receiving end from the codebook based on the reference signal, wherein,

Matrix X ₁ is determined according to θ ₁ and matrix X ₂ is determined according to θ ₂ and

Determined, θ ₁ represents the phase difference between the two adjacent antennas in the first antenna group of the transmitting end for the transmission signal weighted value of the same transmission layer, and θ ₂ represents that the two adjacent antennas in the second antenna group of the transmitting end are for the same transmission The phase difference of the weighted value of the layer transmit signal,

represents the phase difference of the weighted values of the signals transmitted by the first antenna group and the second antenna group for the same transmission layer and

M is a positive integer, n is a non-negative integer smaller than M, at least one precoding matrix in the codebook has different θ ₁ and θ ₂ , and the first antenna group and the second antenna group belong to the same multi-antenna system.

θ₁和θ₂分别表示第一天线组和第二天线组中相邻两根天线针对同一传输层发射信号加权值的相位差。这样，可以根据天线间距情况来选择合适的预编码矩阵，保证天线的弱相关性，因此，发射端基于接收端反馈的从本发明的码本结构中选择的预编码矩阵进行预编码，有效地提高预编码的精度，从而减少性能损失，提高系统的吞吐量。Based on the above solution, the transmitting end receives the precoding matrix indication PMI sent by the receiving end, and determines according to the precoding matrix indication PMI that the receiving end selects the precoding matrix W from the codebook based on the reference signal, wherein,

θ ₁ and θ ₂ respectively represent the phase difference of the weighted values of signals transmitted by two adjacent antennas in the first antenna group and the second antenna group with respect to the same transmission layer. In this way, an appropriate precoding matrix can be selected according to the antenna spacing to ensure the weak correlation of the antennas. Therefore, the transmitting end performs precoding based on the precoding matrix selected from the codebook structure of the present invention fed back by the receiving end, effectively Improve the precision of precoding, thereby reducing performance loss and improving system throughput.

The transmitting end 400 may implement the various steps involved in the transmitting end in the methods in FIGS. 1 to 2 , and will not be described in detail in order to avoid repetition.

Optionally, as an embodiment, the precoding matrix W corresponds to a rank indication, and the rank indication corresponds to the number of useful transmission layers.

Specifically, the codebook whose rank indication is 1 may be the above formula (1); or the codebook whose rank indication is 2 may be the above formula (2).

The codebook in the present invention may also be a codebook with a rank indication of other values. For the convenience of description, the present invention takes a codebook with a rank indication of 1 and a codebook with a rank indication of 2 as examples for description. It should be understood that this The invention is not limited to this.

It should also be understood that the above codebook is represented in the form of a single codebook structure, of course, it can also be represented in the form of a double codebook structure, which is not limited in the present invention.

Optionally, in an implementation manner, taking the rank indication as 1 and 2 as an example, when the rank indication is 1, the precoding matrix determined by the determining unit 402 may be the above formula (3); or, when the rank indication is 2, the precoding matrix determined by the determining unit 402 may be the above formula (4). For specific examples, reference may be made to the above, and details are not repeated here.

Optionally, the precoding matrix indication PMI that the receiving unit 401 can specifically use to receive may include a first precoding matrix indication PMI ₁ and a second precoding matrix indication PMI ₂ . Optionally, PMI ₁ and PMI ₂ may have the same or different granularity in the time domain or frequency domain (or based on different subframe periods or subband sizes), and the receiving unit 401 may be specifically configured to receive at a longer time interval The PMI ₁ sent by the receiving end receives the PMI ₂ sent by the receiving end at a short time interval. The determining unit 402 may be specifically configured to: determine W _{1 selected by the receiver from the codebook based on the reference signal according to PMI 1 ,} and determine W ₂ ¹ or W ₂ ^{2 selected by the receiver from the codebook according to PMI 2} _. Correspondingly, the determining unit 402 may also be specifically configured to: determine the precoding matrix W according to W ₁ and W ₂ ¹ , or determine the precoding matrix W according to W ₁ and W ₂ ² .

Optionally, W ₁ is a matrix representing the channel characteristics of the wideband, both W ₂ ¹ and W ₂ ² are matrices representing the channel characteristics of the sub-band, and the superscript number in W ₂ represents the value of the rank; or W ₁ is a representation of the rank For the long-term channel characteristic matrix, both W ₂ ¹ and W ₂ ² are matrices representing short-term channel characteristics.

Of course, the determining unit 402 can be specifically configured to directly determine the selected precoding matrix W through a PMI received by the receiving unit 401 and sent by the receiving end. For example, the codebook has a total of 256 precoding matrices. When the PMI sent by the receiving end is 0, the determining unit 402 determines that the receiving end selects the first precoding matrix in the 256 precoding matrices of the codebook, and when the receiving unit 401 receives that the PMI sent by the receiving end is 1, the determining unit 402 determines that the receiving end selects the second precoding matrix in the 256 precoding matrices of the codebook, . It should be understood that the embodiment of the present invention does not limit the manner in which the UE indicates the precoding matrix.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the receiving unit 401 of the transmitting end 400 may receive the precoding matrix indication PMI sent by the receiving end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, a column vector is independently selected in the matrix X by the column selection vectors Y1 and Y2 in the embodiment of the present invention, thereby ensuring the weak correlation of the codebook corresponding to the antennas with larger spacing.

Optionally, in another implementation manner, when the rank indication is 1, the precoding matrix determined by the determining unit 402 may be the above formula (12) or (13). For specific examples, reference may be made to the above, and details are not repeated here.

Optionally, the precoding matrix indication PMI that the receiving unit 401 can specifically use to receive may include a seventh precoding matrix indication PMI ₇ and an eighth precoding matrix indication PMI ₈ . Optionally, PMI ₇ and PMI ₈ may have the same or different granularity in time domain or frequency domain (or based on different subframe periods or subband sizes). The receiving unit 401 may be specifically configured to receive the PMI ₇ sent by the receiving end at a relatively long time interval, and receive the PMI ₈ sent by the receiving end at a short time interval. The determining unit 402 may be specifically configured to: determine W ₁ selected by the receiver from the codebook based on the reference signal according to PMI ₇ , and determine W ₄ ¹ selected by the receiver from the codebook according to PMI ₈ . Correspondingly, the determining unit 402 may also be specifically configured to: determine the precoding matrix W according to W ₁ and W ₄ ¹ .

Optionally, W ₃ is a matrix representing a wideband channel characteristic, W ₄ ¹ is a matrix representing a sub-band channel characteristic, or W ₃ is a matrix representing a long-term channel characteristic, and W ₄ ¹ is a matrix representing a short-term channel characteristic. matrix.

Optionally, in another implementation manner, when the rank indication is 2, the precoding matrix determined by the determining unit 402 may be the above formula (14) or (16). For specific examples, reference may be made to the above, and details are not repeated here.

Optionally, the precoding matrix indication PMI that the receiving unit 401 can specifically use to receive may include a ninth precoding matrix indication PMI ₉ and a tenth precoding matrix indication PMI ₁₀ . The receiving unit 401 may be specifically configured to receive the PMI ₉ sent by the receiving end at a relatively long time interval, and receive the PMI ₁₀ sent by the receiving end at a short time interval. The determining unit 402 may be specifically configured to: determine W ₁ selected by the receiver from the codebook based on the reference signal according to PMI ₉ , and determine W ₄ ² selected by the receiver from the codebook according to PMI ₁₀ . Correspondingly, the determining unit 402 may also be specifically configured to: determine the precoding matrix W according to W ₁ and W ₄ ² .

Optionally, W ₃ is a matrix representing the wideband channel characteristics, and W ₄ ² is a matrix representing the sub-band channel characteristics, or W ₃ is a matrix representing the long-term channel characteristics, and W ₄ ² is the short-term channel characteristics. matrix.

Therefore, through the selection of θ' in the embodiment of the present invention, the weak correlation of the codebook corresponding to the antennas with larger spacing is guaranteed.

和

其中，N＝2^k，k为非负整数，A为能整除N的正整数(例如，N＝16，A＝2)，M为小于N的正整数，i₁为小于(N/A-1)的非负整数，i₂和i₃均为正整数且i₂和i₃相互独立，

为向下取整运算符号。即N为2的幂次，可以取值为0，2，4，8……，等等，P∈{0,1,L,N-1}，i₁∈{0,1,L,N/A-1}。Optionally, in another implementation manner, θ ₁ and θ ₂ can be respectively taken as

and

Among them, N=2 ^k , k is a non-negative integer, A is a positive integer that can divide N (for example, N=16, A=2), M is a positive integer less than N, i ₁ is less than (N/A- 1) is a non-negative integer, i ₂ and i ₃ are both positive integers and i ₂ and i ₃ are independent of each other,

Operator symbol for rounding down. That is, N is a power of 2, which can be 0, 2, 4, 8..., etc., P∈{0,1,L,N-1}, i ₁ ∈{0,1,L,N /A-1}.

Optionally, the receiving unit 401 may be specifically configured to receive the third precoding matrix indication PMI ₃ and the fourth precoding matrix indication PMI ₄ sent by the receiving end, and further, receive the PMI sent by the receiving end in the same or different time periods. ₃ and PMI ₄ . The determining unit 402 may be specifically configured to determine i ₁ according to PMI ₃ , and determine i ₂ and i ₃ according to PMI ₄ . Specifically, PMI ₄ may be a joint encoded value of i ₂ and i ₃ , PMI ₄ =P·i ₂ +i ₃ . The determining unit 402 may be specifically configured to determine i _{2 and i 3 according to the corresponding relationship between the value of PMI 4 and i 2 and i 3 .}

In other words, PMI ₃ and PMI ₄ can have different granularity in time domain or frequency domain. Certainly, the determining unit 402 may be specifically configured to directly determine the selected precoding matrix W through a PMI received by the receiving unit 401 and sent by the receiving end. For specific implementation manners, reference may be made to the foregoing embodiments, which will not be repeated here.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the receiving unit 401 of the transmitting end 400 may receive the precoding matrix indication PMI sent by the receiving end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, in the embodiment of the present invention, θ ₁ and θ ₂ can be independently selected by i ₂ and i ₃ respectively according to the current channel characteristics, which ensures the weak correlation of codebooks corresponding to antennas with larger spacing.

和

其中，N＝2^k，k为非负整数，A为能整除N的正整数，P为小于N的正整数，i₁为小于(N/A-1)的非负整数，i₄为小于(PM-1)的正整数(例如P＝4，M＝4，i₄<15)，

为向下取整运算符号，mod为取模运算符号。即N为2的幂次，可以取值为0，2，4，8……，等等，P∈{0,1,L,N-1}，i₁∈{0,1,L,N/A-1}。Optionally, in another implementation manner, θ ₁ and θ ₂ can also be respectively set as

and

Among them, N=2 ^k , k is a non-negative integer, A is a positive integer that can divide N, P is a positive integer less than N, i ₁ is a non-negative integer less than (N/A-1), and i ₄ is less than (PM-1) positive integer (eg P=4, M=4, i ₄ <15),

is a round-down operator, and mod is a modulo operator. That is, N is a power of 2, which can be 0, 2, 4, 8..., etc., P∈{0,1,L,N-1}, i ₁ ∈{0,1,L,N /A-1}.

Optionally, the receiving unit 401 may be specifically configured to receive the fifth precoding matrix indication PMI ₅ and the sixth precoding matrix indication PMI ₆ sent by the receiving end, and further, receive the PMI sent by the receiving end in the same or different time periods. ₅ and PMI ₆ . The determining unit 402 may be specifically configured to determine i ₁ according to PMI ₅ and i ₄ according to PMI ₆ . In other words, PMI ₅ and PMI ₆ can have different granularity in time domain or frequency domain. Certainly, the determining unit 402 may be specifically configured to directly determine the selected precoding matrix W through a PMI received by the receiving unit 401 and sent by the receiving end. For specific implementation manners, reference may be made to the foregoing embodiments, which will not be repeated here.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the receiving unit 401 of the transmitting end 400 may receive the precoding matrix indication PMI sent by the receiving end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Therefore, in this embodiment of the present invention, θ ₁ and θ ₂ can be determined by i ₄ according to the current channel characteristics, and θ ₁ and θ ₂ in the selected precoding matrix can be the same or different, ensuring the codebook corresponding to the antennas with larger spacing weak correlation.

和θ₂＝θ₁+Δθ。其中，N＝2^k，k为非负整数，m为小于N的非负整数，Vθ＝2πt，t的绝对值小于1，例如，t为1/8，-1/16、-1/32、0、1/32，1/16或1/8等。Optionally, in another implementation manner, θ ₁ and θ ₂ can also be respectively set as

and θ ₂ =θ ₁ +Δθ. Among them, N=2 ^k , k is a non-negative integer, m is a non-negative integer less than N, Vθ=2πt, the absolute value of t is less than 1, for example, t is 1/8, -1/16, -1/32 , 0, 1/32, 1/16 or 1/8 etc.

Similarly, the receiving unit 401 may be specifically configured to receive two precoding matrix indications sent by the receiving end, where the two precoding matrix indications respectively indicate θ ₁ and Δθ. Further, the two precoding matrix indications sent by the receiving end may also be received in the same or different time periods, in other words, the two precoding matrix indications may have different granularity in time domain or frequency domain. The determining unit 402 may be specifically configured to determine the precoding matrix W through θ ₁ and Δθ. Certainly, the determining unit 402 may be specifically configured to directly determine the selected precoding matrix W through a PMI received by the receiving unit 401 and sent by the receiving end. For specific implementation manners, reference may be made to the foregoing embodiments, which will not be repeated here.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the receiving unit 401 of the transmitting end 400 may receive the precoding matrix indication PMI sent by the receiving end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, in the embodiment of the present invention, the phase deviation Δθ between θ ₁ and θ ₂ can be used according to the current channel characteristics, and Δθ can be specified in a limited variation range, so as to ensure the weak correlation of the codebook corresponding to the antennas with larger spacing .

Optionally, as another embodiment, the determining unit 402 may also be configured to: perform row permutation or column permutation on the precoding matrix W according to the number of the antenna.

It should be pointed out that other equivalent matrices to represent the above codebook (or precoding matrix) all fall within the scope of the present invention. For example, a precoding matrix after row or column permutation of the precoding matrix W in the embodiment of the present invention also falls within the scope of the present invention, for example, different antenna numbers will correspondingly lead to row permutation of the precoding matrix.

Optionally, as another embodiment, the transmitting end 400 may further include a sending unit 403, where the sending unit 403 is configured to send a reference signal to the receiving end, so that the receiving end selects the precoding matrix W from the codebook based on the reference signal. Wherein, the reference signal includes at least one of the following: CSI RS, DM RS, or CRS, etc.

The embodiments of the present invention further provide device embodiments for implementing the steps and methods in the above method embodiments. FIG. 5 shows an embodiment of a device, in which the device 500 includes a processor 501 , a memory 502 , a transmitter 503 and a receiver 504 . The processor 501 controls the operation of the device 500, and the processor 501 may also be referred to as a CPU (Central Processing Unit, central processing unit). Memory 502 may include read-only memory and random access memory, and provides instructions and data to processor 501 . A portion of memory 502 may also include non-volatile row random access memory (NVRAM). The processor 501, the memory 502, the transmitter 503 and the receiver 504 are coupled together through a bus system 55, wherein the bus system 510 includes a power bus, a control bus and a status signal bus in addition to a data bus. However, for clarity of illustration, the various buses are labeled as bus system 510 in the figure.

The methods disclosed in the foregoing embodiments of the present invention may be applied to the foregoing device 500 . Wherein, the processor 501 may be an integrated circuit chip with signal processing capability. In the implementation process, each step of the above-mentioned method can be completed by an integrated logic circuit of hardware in the processor 501 or an instruction in the form of software.

Further, FIG. 6 is a structural block diagram of a receiving end according to another embodiment of the present invention. The receiving end 600 includes a processor 601 and a transmitter 602 .

矩阵X₁是根据θ₁确定的，矩阵X₂是根据θ₂和

确定的，θ₁表示发射端第一天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，θ₂表示发射端第二天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，

表示第一天线组和第二天线组针对同一传输层发射信号加权值的相位差且

M为正整数，n为小于M的非负整数，在码本中至少有一个预编码矩阵的θ₁和θ₂不相同，第一天线组和第二天线组属于同一个多天线系统。The processor 601 is configured to select the precoding matrix W from the codebook based on the reference signal, wherein,

Matrix X ₁ is determined according to θ ₁ and matrix X ₂ is determined according to θ ₂ and

Determined, θ ₁ represents the phase difference between the two adjacent antennas in the first antenna group of the transmitting end for the transmission signal weighted value of the same transmission layer, and θ ₂ represents that the two adjacent antennas in the second antenna group of the transmitting end are for the same transmission The phase difference of the weighted value of the layer transmit signal,

represents the phase difference of the weighted values of the signals transmitted by the first antenna group and the second antenna group for the same transmission layer and

M is a positive integer, n is a non-negative integer smaller than M, at least one precoding matrix in the codebook has different θ ₁ and θ ₂ , and the first antenna group and the second antenna group belong to the same multi-antenna system.

The transmitter 602 is configured to send the precoding matrix indication PMI to the transmitting end, so that the transmitting end determines the precoding matrix W selected by the processor 601 according to the PMI.

A multi-antenna system refers to a system in which the transmitter and receiver communicate through multiple antennas. Compared with a single-antenna system, multiple antennas at the transmitting end and the receiving end can form spatial diversity gain or multiplexing gain, which can effectively improve transmission reliability and system capacity. Diversity gain and multiplexing gain in a multi-antenna system can generally be obtained through a precoding method at the transmitter and a receive combining algorithm at the receiver. For example, in an LTE system, 4 antennas are used at the transmitting end, and 2 antennas are used at the receiving end.

In addition, the multi-antenna system according to the embodiment of the present invention can also be applied to the scenario of multi-point joint transmission. Multi-point joint transmission refers to the joint transmission of signals by multiple transmitters for the same user. For example, transmitter A has two antennas. The transmitter B also has 2 antennas, and both transmitters perform joint transmission to the receiver at the same time. Then the signal received by the receiving end can be regarded as a signal sent by a 4-antenna base station.

θ₁和θ₂分别表示第一天线组和第二天线组中相邻两根天线针对同一传输层发射信号加权值的相位差。这样，可以根据天线间距情况来选择合适的预编码矩阵，保证天线的弱相关性，因此，发射端基于接收端反馈的从本发明的码本结构中选择的预编码矩阵进行预编码，有效地提高预编码的精度，从而减少性能损失，提高系统的吞吐量。Based on the above solution, the receiving end selects the precoding matrix W from the codebook based on the reference signal, wherein,

θ ₁ and θ ₂ respectively represent the phase difference of the weighted values of signals transmitted by two adjacent antennas in the first antenna group and the second antenna group with respect to the same transmission layer. In this way, an appropriate precoding matrix can be selected according to the antenna spacing to ensure the weak correlation of the antennas. Therefore, the transmitting end performs precoding based on the precoding matrix selected from the codebook structure of the present invention fed back by the receiving end, effectively Improve the precision of precoding, thereby reducing performance loss and improving system throughput.

In this embodiment of the present invention, the transmitting end may be a base station, and correspondingly, the receiving end may be a UE; or the transmitting end may be a UE, and correspondingly, the receiving end may be a base station. It should be understood that this embodiment of the present invention is not limited thereto.

The receiving end 600 may implement various steps involved in the receiving end in the methods of FIG. 1 to FIG. 2 , which will not be described in detail in order to avoid repetition.

Optionally, as an embodiment, the processor 601 may be further configured to determine a rank indication based on the reference signal, where the rank indication corresponds to the number of useful transmission layers. The processor 601 is specifically configured to: select the precoding matrix W corresponding to the rank indication from the codebook based on the reference signal.

Specifically, when the rank indication determined by the processor 601 is 1, the precoding matrix selected by the processor 601 may be the above formula (1); or, when the rank indication determined by the processor 601 is 2, the precoding matrix selected by the processor 601 The matrix may be the above formula (2).

The above examples are only exemplary, and are not intended to limit the scope of the present invention. The codebook in the present invention may also be a codebook with a rank indication of other values. For the convenience of description, the codebook with a rank indication of 1 is used in the present invention. A codebook with a sum rank indication of 2 is taken as an example for description, and it should be understood that this is not limited in the present invention.

It should also be understood that the above codebook is represented in the form of a single codebook structure, of course, it can also be represented in the form of a double codebook structure, which is not limited in the present invention.

Optionally, in an implementation manner, taking the rank indication as 1 and 2 as an example, when the rank indication determined by the processor 601 is 1, the precoding matrix selected by the processor 601 may be the above formula (3); or , when the rank indication determined by the processor 601 is 2, the precoding matrix selected by the processor 601 may be the above formula (4). For specific examples, reference may be made to the above, and details are not repeated here.

Optionally, W ₁ is a matrix representing the channel characteristics of the wideband, both W ₂ ¹ and W ₂ ² are matrices representing the channel characteristics of the sub-band, and the superscript number in W ₂ represents the value of the rank; or W ₁ is a representation of the rank For the long-term channel characteristic matrix, both W ₂ ¹ and W ₂ ² are matrices representing short-term channel characteristics. Correspondingly, the transmitting end may receive the PMI ₁ sent by the receiving end at a relatively long time interval, and receive the PMI ₂ sent by the receiving end at a short time interval.

Optionally, the precoding matrix indication PMI sent by the transmitter 602 may include a first precoding matrix indication PMI ₁ and a second precoding matrix indication PMI ₂ , where PMI ₁ is used to indicate W ₁ , and PMI ₂ is used to indicate W ₂ ¹ or W ₂ ² .

Therefore, a column vector is independently selected in the matrix X by the column selection vectors Y1 and Y2 in the embodiment of the present invention, thereby ensuring the weak correlation of the codebook corresponding to the antennas with larger spacing.

Optionally, in another implementation manner, when the rank indication determined by the processor 601 is 1, the precoding matrix selected by the processor 601 may be the above formula (12) or (13). For a specific example, refer to the above, It will not be repeated here.

Optionally, W ₃ is a matrix representing a wideband channel characteristic, W ₄ ¹ is a matrix representing a sub-band channel characteristic, or W ₃ is a matrix representing a long-term channel characteristic, and W ₄ ¹ is a matrix representing a short-term channel characteristic. matrix.

Optionally, the precoding matrix indication PMI sent by the transmitter 602 may include a seventh precoding matrix indication PMI ₇ and an eighth precoding matrix indication PMI ₈ , where PMI ₇ is used to indicate W ₃ , and PMI ₈ is used to indicate W ₄ ¹ . In other words, PMI ₇ and PMI ₈ may have the same or different granularity in time domain or frequency domain (or based on different subframe periods or subband sizes). Correspondingly, the transmitting end may receive the PMI ₇ sent by the transmitter 602 at a longer time interval, and receive the PMI ₈ sent by the transmitter 602 at a shorter time interval.

Optionally, in another implementation manner, when the rank indication determined by the processor 601 is 2, the precoding matrix selected by the processor 601 may be the above formula (14) or (16). For a specific example, refer to the above, It will not be repeated here.

Optionally, W ₃ is a matrix representing the wideband channel characteristics, and W ₄ ² is a matrix representing the sub-band channel characteristics, or W ₃ is a matrix representing the long-term channel characteristics, and W ₄ ² is the short-term channel characteristics. matrix.

Optionally, the precoding matrix indication PMI sent by the transmitter 602 may include a ninth precoding matrix indication PMI ₉ and a tenth precoding matrix indication PMI ₁₀ , where PMI ₉ is used to indicate W ₃ , and PMI ₁₀ is used to indicate W ₄ ² . Correspondingly, the transmitting end may receive the PMI ₉ sent by the transmitter 602 at a longer time interval, and receive the PMI ₁₀ sent by the transmitter 602 at a shorter time interval.

Therefore, through the selection of θ' in the embodiment of the present invention, the weak correlation of the codebook corresponding to the antennas with larger spacing is guaranteed.

和

其中，N＝2^k，k为非负整数，A为能整除N的正整数(例如，N＝16，A＝2)，M为小于N的正整数，i₁为小于(N/A-1)的非负整数，i₂和i₃均为正整数且i₂和i₃相互独立，

为向下取整运算符号。即N为2的幂次，可以取值为0，2，4，8……，等等，P∈{0,1,L,N-1}，i₁∈{0,1,L,N/A-1}。Optionally, in another implementation manner, θ ₁ and θ ₂ can be respectively taken as

and

Among them, N=2 ^k , k is a non-negative integer, A is a positive integer that can divide N (for example, N=16, A=2), M is a positive integer less than N, i ₁ is less than (N/A- 1) is a non-negative integer, i ₂ and i ₃ are both positive integers and i ₂ and i ₃ are independent of each other,

Operator symbol for rounding down. That is, N is a power of 2, which can be 0, 2, 4, 8..., etc., P∈{0,1,L,N-1}, i ₁ ∈{0,1,L,N /A-1}.

Optionally, the precoding matrix indication PMI sent by the transmitter 602 may include a third precoding matrix indication PMI ₃ and a fourth precoding matrix indication PMI ₄ , where PMI ₃ is used to indicate i ₁ , and PMI ₄ is used to indicate i ₂ and i ₃ , specifically, PMI ₄ may be the jointly encoded value of i ₂ and i ₃ . The transmitter can determine i ₂ and i ₃ according to the corresponding relationship between the value of PMI ₄ and i ₂ and i ₃ . For example, the transmitter can preset the corresponding relationship between PMI ₄ and i ₂ , determine i ₂ according to the value of PMI ₄ , and then determine i ₃ according to the relationship PMI ₄ =P·i ₂ +i ₃ ; similarly, the transmitter can preset The corresponding relationship between PMI ₄ and i ₃ , i ₃ is determined by the value of PMI ₄ , and i ₂ is determined according to the relational expression PMI ₄ =P·i ₂ +i ₃ .

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Therefore, in the embodiment of the present invention, θ ₁ and θ ₂ can be independently selected by i ₂ and i ₃ respectively according to the current channel characteristics, which ensures the weak correlation of codebooks corresponding to antennas with larger spacing.

和

其中，N＝2^k，k为非负整数，A为能整除N的正整数，P为小于N的正整数，i₁为小于(N/A-1)的非负整数，i₄为小于(PM-1)的正整数(例如P＝4，M＝4，i₄<15)，

为向下取整运算符号，mod为取模运算符号。即N为2的幂次，可以取值为0，2，4，8……，等等，P∈{0,1,L,N-1}，i₁∈{0,1,L,N/A-1}。Optionally, in another implementation manner, θ ₁ and θ ₂ can also be respectively set as

and

Among them, N=2 ^k , k is a non-negative integer, A is a positive integer that can divide N, P is a positive integer less than N, i ₁ is a non-negative integer less than (N/A-1), and i ₄ is less than (PM-1) positive integer (eg P=4, M=4, i ₄ <15),

is a round-down operator, and mod is a modulo operator. That is, N is a power of 2, which can be 0, 2, 4, 8..., etc., P∈{0,1,L,N-1}, i ₁ ∈{0,1,L,N /A-1}.

Optionally, the precoding matrix indication PMI sent by the transmitter 602 may include a fifth precoding matrix indication PMI ₅ and a sixth precoding matrix indication PMI ₆ , where the PMI ₅ is used to indicate i ₁ , and the PMI ₆ is used to indicate i ₄ .

和θ₂＝θ₁+Δθ。其中，N＝2^k，k为非负整数，m为小于N的非负整数，Vθ＝2πt，t的绝对值小于1，例如，t为1/8，-1/16、-1/32、0、1/32，1/16或1/8等。Optionally, in another implementation manner, θ ₁ and θ ₂ can also be respectively set as

and θ ₂ =θ ₁ +Δθ. Among them, N=2 ^k , k is a non-negative integer, m is a non-negative integer less than N, Vθ=2πt, the absolute value of t is less than 1, for example, t is 1/8, -1/16, -1/32 , 0, 1/32, 1/16 or 1/8 etc.

Therefore, in the embodiment of the present invention, the phase deviation Δθ between θ ₁ and θ ₂ can be used according to the current channel characteristics, and Δθ can be specified in a limited variation range, so as to ensure the weak correlation of the codebook corresponding to the antennas with larger spacing .

Optionally, as another embodiment, the processor 601 may be further configured to: perform row permutation or column permutation on the precoding matrix W according to the number of the antenna.

It should be pointed out that other equivalent matrices to represent the above codebook (or precoding matrix) all fall within the scope of the present invention. For example, a precoding matrix after row or column permutation of the precoding matrix W in the embodiment of the present invention also falls within the scope of the present invention, for example, different antenna numbers will correspondingly lead to row permutation of the precoding matrix.

Optionally, as another embodiment, the receiving end 600 may further include a receiver 603. The receiver 603 is configured to receive a reference signal sent by the transmitting end. The processor 602 is specifically configured to determine the rank indication based on the reference signal received by the receiver 603 ; or, the processor 6021 is specifically configured to select the precoding matrix W from the codebook based on the reference signal received by the receiver 603 . Wherein, the reference signal includes at least one of the following: CSI RS, DM RS, or CRS, etc.

FIG. 7 is a structural block diagram of a transmitter according to another embodiment of the present invention. The transmitter 700 in FIG. 7 includes a receiver 701 and a processor 702 .

The receiver 701 is configured to receive the precoding matrix indication PMI sent by the receiving end.

矩阵X₁是根据θ₁确定的，矩阵X₂是根据θ₂和

确定的，θ₁表示发射端第一天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，θ₂表示发射端第二天线组中的相邻两根天线针对同一传输层发射信号加权值的相位差，

表示第一天线组和第二天线组针对同一传输层发射信号加权值的相位差且

M为正整数，n为小于M的非负整数，在码本中至少有一个预编码矩阵的θ₁和θ₂不相同，第一天线组和第二天线组属于同一个多天线系统。The processor 702 is configured to determine, according to the precoding matrix instruction PMI received by the receiver 701, the precoding matrix W selected by the receiver from the codebook based on the reference signal, wherein,

Matrix X ₁ is determined according to θ ₁ and matrix X ₂ is determined according to θ ₂ and

Determined, θ ₁ represents the phase difference between the two adjacent antennas in the first antenna group of the transmitting end for the transmission signal weighted value of the same transmission layer, and θ ₂ represents that the two adjacent antennas in the second antenna group of the transmitting end are for the same transmission The phase difference of the weighted value of the layer transmit signal,

represents the phase difference of the weighted values of the signals transmitted by the first antenna group and the second antenna group for the same transmission layer and

M is a positive integer, n is a non-negative integer smaller than M, at least one precoding matrix in the codebook has different θ ₁ and θ ₂ , and the first antenna group and the second antenna group belong to the same multi-antenna system.

θ₁和θ₂分别表示第一天线组和第二天线组中相邻两根天线针对同一传输层发射信号加权值的相位差。这样，可以根据天线间距情况来选择合适的预编码矩阵，保证天线的弱相关性，因此，发射端基于接收端反馈的从本发明的码本结构中选择的预编码矩阵进行预编码，有效地提高预编码的精度，从而减少性能损失，提高系统的吞吐量。Based on the above solution, the transmitting end receives the precoding matrix indication PMI sent by the receiving end, and determines according to the precoding matrix indication PMI that the receiving end selects the precoding matrix W from the codebook based on the reference signal, wherein,

θ ₁ and θ ₂ respectively represent the phase difference of the weighted values of signals transmitted by two adjacent antennas in the first antenna group and the second antenna group with respect to the same transmission layer. In this way, an appropriate precoding matrix can be selected according to the antenna spacing to ensure the weak correlation of the antennas. Therefore, the transmitting end performs precoding based on the precoding matrix selected from the codebook structure of the present invention fed back by the receiving end, effectively Improve the precision of precoding, thereby reducing performance loss and improving system throughput.

The transmitting end 700 may implement the various steps involved in the transmitting end in the methods in FIGS. 1 to 2 , and will not be described in detail to avoid repetition.

Optionally, as an embodiment, the precoding matrix W corresponds to a rank indication, and the rank indication corresponds to the number of useful transmission layers.

Specifically, the codebook whose rank indication is 1 may be the above formula (1); or the codebook whose rank indication is 2 may be the above formula (2).

The codebook in the present invention may also be a codebook with a rank indication of other values. For the convenience of description, the present invention takes a codebook with a rank indication of 1 and a codebook with a rank indication of 2 as examples for description. It should be understood that this The invention is not limited to this.

It should also be understood that the above codebook is represented in the form of a single codebook structure, of course, it can also be represented in the form of a double codebook structure, which is not limited in the present invention.

Optionally, in an implementation manner, taking the rank indication as 1 and 2 as an example, when the rank indication is 1, the precoding matrix determined by the processor 702 may be the above formula (3); or, when the rank indication is 2, the precoding matrix determined by the processor 702 may be the above formula (4). For specific examples, reference may be made to the above, and details are not repeated here.

Optionally, the precoding matrix indication PMI that the receiver 701 can specifically use to receive may include a first precoding matrix indication PMI ₁ and a second precoding matrix indication PMI ₂ . Optionally, PMI ₁ and PMI ₂ may have the same or different granularity in time domain or frequency domain (or based on different subframe periods or subband sizes), and the receiver 701 may be specifically configured to receive at longer time intervals The PMI ₁ sent by the receiving end receives the PMI ₂ sent by the receiving end at a short time interval. The processor 702 may be specifically configured to: determine W _{1 selected by the receiver from the codebook based on the reference signal according to PMI 1 ,} and determine W ₂ ¹ or W ₂ ^{2 selected by the receiver from the codebook according to PMI 2} _. Correspondingly, the processor 702 may also be specifically configured to: determine the precoding matrix W according to W ₁ and W ₂ ¹ , or determine the precoding matrix W according to W ₁ and W ₂ ² .

Optionally, W ₁ is a matrix representing the channel characteristics of the wideband, both W ₂ ¹ and W ₂ ² are matrices representing the channel characteristics of the sub-band, and the superscript number in W ₂ represents the value of the rank; or W ₁ is a representation of the rank For the long-term channel characteristic matrix, both W ₂ ¹ and W ₂ ² are matrices representing short-term channel characteristics.

Of course, the processor 702 can be specifically configured to directly determine the selected precoding matrix W through a PMI received by the receiver 701 and sent by the receiving end. For example, there are 256 precoding matrices in the codebook. When the PMI sent by the receiving end is 0, the processor 702 determines that the receiving end selects the first precoding matrix in the 256 precoding matrices of the codebook. When the receiver 701 receives that the PMI sent by the receiving end is 1, the processor 702 Determines that the receiving end selects the second precoding matrix in the 256 precoding matrices of the codebook, . It should be understood that the embodiment of the present invention does not limit the manner in which the UE indicates the precoding matrix.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the receiver 701 of the transmitting end 700 may receive the precoding matrix indication PMI sent by the receiving end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, a column vector is independently selected in the matrix X by the column selection vectors Y1 and Y2 in the embodiment of the present invention, thereby ensuring the weak correlation of the codebook corresponding to the antennas with larger spacing.

Optionally, in another implementation manner, when the rank indication is 1, the precoding matrix determined by the processor 702 may be the above formula (12) or (13). For specific examples, reference may be made to the above, and details are not repeated here.

Optionally, the precoding matrix indication PMI that the receiver 701 can specifically use to receive may include a seventh precoding matrix indication PMI ₇ and an eighth precoding matrix indication PMI ₈ . Optionally, PMI ₇ and PMI ₈ may have the same or different granularity in time domain or frequency domain (or based on different subframe periods or subband sizes). The receiver 701 may be specifically configured to receive the PMI ₇ sent by the receiving end at a relatively long time interval, and receive the PMI ₈ sent by the receiving end at a short time interval. The processor 702 may be specifically configured to: determine W ₁ selected by the receiver from the codebook based on the reference signal according to PMI ₇ , and determine W ₄ ¹ selected by the receiver from the codebook according to PMI ₈ . Correspondingly, the processor 702 may also be specifically configured to: determine the precoding matrix W according to W ₁ and W ₄ ¹ .

Optionally, W ₃ is a matrix representing a wideband channel characteristic, W ₄ ¹ is a matrix representing a sub-band channel characteristic, or W ₃ is a matrix representing a long-term channel characteristic, and W ₄ ¹ is a matrix representing a short-term channel characteristic. matrix.

Optionally, in another implementation manner, when the rank indication is 2, the precoding matrix determined by the processor 702 may be the above formula (14) or (16). For specific examples, reference may be made to the above, and details are not repeated here.

Optionally, the precoding matrix indication PMI that the receiver 701 can specifically use to receive may include a ninth precoding matrix indication PMI ₉ and a tenth precoding matrix indication PMI ₁₀ . The receiver 701 may be specifically configured to receive the PMI ₉ sent by the receiving end at a relatively long time interval, and receive the PMI ₁₀ sent by the receiving end at a short time interval. The processor 702 may be specifically configured to: determine W ₁ selected by the receiver from the codebook based on the reference signal according to PMI ₉ , and determine W ₄ ² selected by the receiver from the codebook according to PMI ₁₀ . Correspondingly, the processor 702 may also be specifically configured to: determine the precoding matrix W according to W ₁ and W ₄ ² .

Optionally, W ₃ is a matrix representing the wideband channel characteristics, and W ₄ ² is a matrix representing the sub-band channel characteristics, or W ₃ is a matrix representing the long-term channel characteristics, and W ₄ ² is the short-term channel characteristics. matrix.

Therefore, through the selection of θ' in the embodiment of the present invention, the weak correlation of the codebook corresponding to the antennas with larger spacing is guaranteed.

和

其中，N＝2^k，k为非负整数，A为能整除N的正整数(例如，N＝16，A＝2)，M为小于N的正整数，i₁为小于(N/A-1)的非负整数，i₂和i₃均为正整数且i₂和i₃相互独立，

为向下取整运算符号。即N为2的幂次，可以取值为0，2，4，8……，等等，P∈{0,1,L,N-1}，i₁∈{0,1,L,N/A-1}。Optionally, in another implementation manner, θ ₁ and θ ₂ can be respectively taken as

and

Among them, N=2 ^k , k is a non-negative integer, A is a positive integer that can divide N (for example, N=16, A=2), M is a positive integer less than N, i ₁ is less than (N/A- 1) is a non-negative integer, i ₂ and i ₃ are both positive integers and i ₂ and i ₃ are independent of each other,

Operator symbol for rounding down. That is, N is a power of 2, which can be 0, 2, 4, 8..., etc., P∈{0,1,L,N-1}, i ₁ ∈{0,1,L,N /A-1}.

Optionally, the receiver 701 may be specifically configured to receive the third precoding matrix indication PMI ₃ and the fourth precoding matrix indication PMI ₄ sent by the receiving end, and further, receive the PMI sent by the receiving end in the same or different time periods. ₃ and PMI ₄ . The processor 702 may be specifically configured to determine i ₁ according to PMI ₃ , and determine i ₂ and i ₃ according to PMI ₄ . Specifically, PMI ₄ may be a joint encoded value of i ₂ and i ₃ , PMI ₄ =P·i ₂ +i ₃ . The processor 702 may be specifically configured to determine i _{2 and i 3 according to the corresponding relationship between the value of PMI 4 and i 2 and i 3 .}

In other words, PMI ₃ and PMI ₄ can have different granularity in time domain or frequency domain. Of course, the processor 702 may be specifically configured to directly determine the selected precoding matrix W through a PMI received by the receiver 701 and sent by the receiving end. For specific implementation manners, reference may be made to the foregoing embodiments, which will not be repeated here.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the receiver 701 of the transmitting end 700 may receive the precoding matrix indication PMI sent by the receiving end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, in the embodiment of the present invention, θ ₁ and θ ₂ can be independently selected by i ₂ and i ₃ respectively according to the current channel characteristics, which ensures the weak correlation of codebooks corresponding to antennas with larger spacing.

和

其中，N＝2^k，k为非负整数，A为能整除N的正整数，P为小于N的正整数，i₁为小于(N/A-1)的非负整数，i₄为小于(PM-1)的正整数(例如P＝4，M＝4，i₄<15)，

为向下取整运算符号，mod为取模运算符号。即N为2的幂次，可以取值为0，2，4，8……，等等，P∈{0,1,L,N-1}，i₁∈{0,1,L,N/A-1}。Optionally, in another implementation manner, θ ₁ and θ ₂ can also be respectively set as

and

Among them, N=2 ^k , k is a non-negative integer, A is a positive integer that can divide N, P is a positive integer less than N, i ₁ is a non-negative integer less than (N/A-1), and i ₄ is less than (PM-1) positive integer (eg P=4, M=4, i ₄ <15),

is a round-down operator, and mod is a modulo operator. That is, N is a power of 2, which can be 0, 2, 4, 8..., etc., P∈{0,1,L,N-1}, i ₁ ∈{0,1,L,N /A-1}.

Optionally, the receiver 701 may be specifically configured to receive the fifth precoding matrix indication PMI ₅ and the sixth precoding matrix indication PMI ₆ sent by the receiving end, and further, receive the PMI sent by the receiving end in the same or different time periods. ₅ and PMI ₆ . The processor 702 may be specifically configured to determine i ₁ according to PMI ₅ and i ₄ according to PMI ₆ . In other words, PMI ₅ and PMI ₆ can have different granularity in time domain or frequency domain. Of course, the processor 702 may be specifically configured to directly determine the selected precoding matrix W through a PMI received by the receiver 701 and sent by the receiving end. For specific implementation manners, reference may be made to the foregoing embodiments, which will not be repeated here.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the receiver 701 of the transmitting end 700 may receive the precoding matrix indication PMI sent by the receiving end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Therefore, in this embodiment of the present invention, θ ₁ and θ ₂ can be determined by i ₄ according to the current channel characteristics, and θ ₁ and θ ₂ in the selected precoding matrix can be the same or different, ensuring the codebook corresponding to the antennas with larger spacing weak correlation.

和θ₂＝θ₁+Δθ。其中，N＝2^k，k为非负整数，m为小于N的非负整数，Vθ＝2πt，t的绝对值小于1，例如，t为1/8，-1/16、-1/32、0、1/32，1/16或1/8等。Optionally, in another implementation manner, θ ₁ and θ ₂ can also be respectively set as

and θ ₂ =θ ₁ +Δθ. Among them, N=2 ^k , k is a non-negative integer, m is a non-negative integer less than N, Vθ=2πt, the absolute value of t is less than 1, for example, t is 1/8, -1/16, -1/32 , 0, 1/32, 1/16 or 1/8 etc.

Similarly, the receiver 701 may be specifically configured to receive two precoding matrix indications sent by the receiving end, where the two precoding matrix indications respectively indicate θ ₁ and Δθ. Further, the two precoding matrix indications sent by the receiving end may also be received in the same or different time periods, in other words, the two precoding matrix indications may have different granularity in time domain or frequency domain. The processor 702 may be specifically configured to determine the precoding matrix W through θ ₁ and Δθ. Of course, the processor 702 may be specifically configured to directly determine the selected precoding matrix W through a PMI received by the receiver 701 and sent by the receiving end. For specific implementation manners, reference may be made to the foregoing embodiments, which will not be repeated here.

It should be understood that the manner in which the receiving end indicates the precoding matrix is not limited in this embodiment of the present invention.

Optionally, the receiver 701 of the transmitting end 700 may receive the precoding matrix indication PMI sent by the receiving end through a physical control channel or a physical shared channel. It should be understood that this embodiment of the present invention does not limit this.

Therefore, in the embodiment of the present invention, the phase deviation Δθ between θ ₁ and θ ₂ can be used according to the current channel characteristics, and Δθ can be specified in a limited variation range, so as to ensure the weak correlation of the codebook corresponding to the antennas with larger spacing .

Optionally, as another embodiment, the processor 702 may be further configured to: perform row permutation or column permutation on the precoding matrix W according to the number of the antenna.

It should be pointed out that other equivalent matrices to represent the above codebook (or precoding matrix) all fall within the scope of the present invention. For example, a precoding matrix after row or column permutation of the precoding matrix W in the embodiment of the present invention also falls within the scope of the present invention, for example, different antenna numbers will correspondingly lead to row permutation of the precoding matrix.

Optionally, as another embodiment, the transmitter 700 may further include a transmitter 703, and the transmitter 703 is configured to send a reference signal to the receiver, so that the receiver selects the precoding matrix W from the codebook based on the reference signal. Wherein, the reference signal includes at least one of the following: CSI RS, DM RS, or CRS, etc.

Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Skilled artisans may implement the described functionality using different methods for each particular application, but such implementations should not be considered beyond the scope of the present invention.

Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the above-described systems, devices and units may refer to the corresponding processes in the foregoing method embodiments, which will not be repeated here.

In the several embodiments provided in this application, it should be understood that the disclosed system, apparatus and method may be implemented in other manners. For example, the apparatus embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored, or not implemented. On the other hand, the shown or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, indirect coupling or communication connection of devices or units, and may be in electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution in this embodiment.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit.

The functions, if implemented in the form of software functional units and sold or used as independent products, may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention can be embodied in the form of a software product in essence, or the part that contributes to the prior art or the part of the technical solution. The computer software product is stored in a storage medium, including Several instructions are used to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, Read-Only Memory (ROM, Read-Only Memory), Random Access Memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program codes .

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention. should be included within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (20)

1. A method of receiving a precoding matrix indication, comprising:

a transmitting end receives a Precoding Matrix Indicator (PMI) from a receiving end;

the transmitting terminal determines that the receiving terminal is based on reference according to the precoding matrix indicator PMIThe signal is a precoding matrix W selected from a codebook, wherein,

matrix X₁Is according to theta₁Determined, matrix X₂Is according to theta₂And

determined, said theta₁The phase difference represents the weighted value of the transmission signal of the same transmission layer of two adjacent antennas in the first antenna group of the transmitting terminal₂A phase difference representing a weighted value of transmission signals of two adjacent antennas in the second antenna group of the transmitting end for the same transmission layer

A phase difference representing a transmission signal weight value of the first antenna group and the second antenna group for the same transmission layer and

m is a positive integer, n is a non-negative integer less than M, and θ of at least one precoding matrix in the codebook₁And theta₂Different, the first antenna group and the second antenna group belong to the same multi-antenna system;

the receiving end is a base station and the transmitting end is user equipment, or the transmitting end is a base station and the receiving end is user equipment.

2. The method of claim 1, wherein the W corresponds to a rank indication corresponding to a number of useful transmission layers.

3. The method of claim 2,

when the rank indication is 1, the

When the rank indication is 2, the

Wherein both the α and β are constants.

4. The method according to any of claims 1 to 3, wherein before the transmitting end receives a precoding matrix indicator, PMI, from the receiving end, the method further comprises:

the transmitting end transmits the reference signal to the receiving end, wherein the reference signal comprises at least one of the following: channel state information reference signal (CSI RS), demodulation reference signal (DM RS) and cell specific reference signal (CRS).

5. A transmitting end, comprising:

a receiving unit, configured to receive a precoding matrix indicator PMI from a receiving end;

a determining unit, configured to determine a precoding matrix W selected by the receiving end from a codebook based on a reference signal according to the precoding matrix indicator PMI received by the receiving unit, wherein the precoding matrix W is

Matrix X₁Is according to theta₁Determined, matrix X₂Is according to theta₂And

determined, said theta₁The phase difference represents the weighted value of the transmission signal of the same transmission layer of two adjacent antennas in the first antenna group of the transmitting terminal₂A phase difference representing a weighted value of transmission signals of two adjacent antennas in the second antenna group of the transmitting end for the same transmission layer

A phase difference representing a transmit signal weight value for the same transmission layer for the first and second antenna groups and

m is a positive integer, n is a non-negative integer less than M, and θ of at least one precoding matrix in the codebook₁And theta₂Different, the first antenna group and the second antenna group belong to the same multi-antenna system;

the receiving terminal is a base station and the transmitting terminal is user equipment, or the transmitting terminal is a base station and the receiving terminal is user equipment, the user equipment is a mobile phone or a computer with a wireless communication function, or the user equipment is a portable, pocket, hand-held, computer-embedded or vehicle-mounted mobile device.

6. The transmitting end of claim 5, wherein the W corresponds to a rank indication corresponding to a number of useful transmission layers.

7. The transmitting end of claim 6,

when the rank indication is 1, the

When the rank indication is 2, the

Wherein both the α and β are constants.

8. The transmitting end according to any one of claims 5 to 7, wherein the transmitting end further comprises a transmitting unit:

the sending unit is configured to send the reference signal to the receiving end, where the reference signal includes at least one of: channel state information reference signal (CSI RS), demodulation reference signal (DM RS) and cell specific reference signal (CRS).

9. A transmitting end, comprising:

a receiver, configured to receive a precoding matrix indicator PMI from a receiving end;

a processor for determining a precoding matrix W selected by the receiving end from a codebook based on a reference signal according to the precoding matrix indicator PMI received by the receiver, wherein the precoding matrix W is obtained by the receiving end

Matrix X₁Is according to theta₁Determined, matrix X₂Is according to theta₂And

is determined by

The phase difference represents the weighted value of the transmission signal of the same transmission layer of two adjacent antennas in the first antenna group of the transmitting terminal₂A phase difference representing a weighted value of transmission signals of two adjacent antennas in the second antenna group of the transmitting end for the same transmission layer

A phase difference representing a transmit signal weight value for the same transmission layer for the first and second antenna groups and

m is a positive integer, n is a non-negative integer less than M, and θ of at least one precoding matrix in the codebook₁And theta₂Different, the first antenna group and the second antenna group belong to the same multi-antenna system;

the receiving end is a base station and the transmitting end is user equipment, or the transmitting end is a base station and the receiving end is user equipment.

10. The transmitting end of claim 9, wherein the W corresponds to a rank indication corresponding to a number of useful transmission layers.

11. The transmitting end of claim 10,

when the rank indication is 1, the

When the rank indication is 2, the

Wherein both the α and β are constants.

12. The transmitting terminal according to any of claims 9 to 11, wherein the transmitting terminal further comprises a transmitter,

the transmitter is configured to transmit the reference signal to the receiving end, where the reference signal includes at least one of: channel state information reference signal (CSI RS), demodulation reference signal (DM RS) and cell specific reference signal (CRS).

13. An integrated circuit chip, wherein the integrated circuit chip comprises an integrated circuit configured to:

receiving a Precoding Matrix Indicator (PMI) from a receiving end;

determining a precoding matrix W selected by the receiving end from a codebook based on a reference signal according to the received precoding matrix indicator PMI, wherein the precoding matrix W is

Matrix X₁Is according to theta₁Determined, matrix X₂Is according to theta₂And

determined, said theta₁The phase difference represents the weighted value of the transmission signal of the same transmission layer of two adjacent antennas in the first antenna group of the transmitting terminal₂A phase difference representing a weighted value of transmission signals of two adjacent antennas in the second antenna group of the transmitting end for the same transmission layer

A phase difference representing a transmit signal weight value for the same transmission layer for the first and second antenna groups and

m is a positive integer, n is a non-negative integer less than M, and θ of at least one precoding matrix in the codebook₁And theta₂Different, the first antenna group and the second antenna group belong to the same multi-antenna system.

14. The integrated circuit chip of claim 13, wherein the W corresponds to a rank indication corresponding to a number of useful transmission layers.

15. The integrated circuit chip of claim 14,

when the rank indication is 1, the

When the rank indication is 2, the

Wherein both the α and β are constants.

16. The integrated circuit chip of any of claims 13 to 15, wherein the integrated circuit is further to: transmitting the reference signal to the receiving end, wherein the reference signal comprises at least one of the following: channel state information reference signal (CSI RS), demodulation reference signal (DM RS) and cell specific reference signal (CRS).

17. A computer-readable storage medium having stored thereon a computer program or instructions which, when executed, perform the steps of:

receiving a Precoding Matrix Indicator (PMI) from a receiving end;

determining a precoding matrix W selected by the receiving end from a codebook based on a reference signal according to the received precoding matrix indicator PMI, wherein the precoding matrix W is

Matrix X₁Is according to theta₁Determined, matrix X₂Is according to theta₂And

determined, said theta₁The phase difference represents the weighted value of the transmission signal of the same transmission layer of two adjacent antennas in the first antenna group of the transmitting terminal₂A phase difference representing a weighted value of transmission signals of two adjacent antennas in the second antenna group of the transmitting end for the same transmission layer

A phase difference representing a transmit signal weight value for the same transmission layer for the first and second antenna groups and

m is a positive integer, n is a non-negative integer less than M, and θ of at least one precoding matrix in the codebook₁And theta₂Different, the first antenna group and the second antenna group belong to the same multi-antenna system.

18. The computer-readable storage medium of claim 17, wherein the W corresponds to a rank indication, the rank indication corresponding to a number of useful transmission layers.

19. The computer-readable storage medium of claim 18,

when the rank indication is 1, the

When the rank indication is 2, the

Wherein both the α and β are constants.

20. A computer-readable storage medium according to any one of claims 17 to 19, wherein the computer program or instructions, when executed, further performs the steps of: transmitting the reference signal to the receiving end, wherein the reference signal comprises at least one of the following: channel state information reference signal (CSI RS), demodulation reference signal (DM RS) and cell specific reference signal (CRS).

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