CN111756417A

CN111756417A - Channel state information feedback method and device

Info

Publication number: CN111756417A
Application number: CN201910345043.6A
Authority: CN
Inventors: 李辉; 高秋彬; 刘正宣; 陈润华
Original assignee: Telecommunications Science and Technology Research Institute Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2019-03-27
Filing date: 2019-04-26
Publication date: 2020-10-09
Anticipated expiration: 2039-04-26
Also published as: CN111756417B

Abstract

The application discloses a channel state information feedback method and device. In the application, a terminal performs channel measurement to obtain a coefficient set for feedback, wherein the coefficient set comprises at least one layer of amplitude coefficient set and at least one layer of phase coefficient set, the amplitude coefficient set comprises a differential amplitude coefficient and a reference amplitude coefficient, and the coefficient set is used for constructing a precoding matrix; and the terminal sends CSI to network equipment, wherein the CSI comprises the coefficient set and the indication information of the strongest amplitude coefficient, and the indication information of the strongest amplitude coefficient is used for indicating the strongest amplitude coefficient of at least one layer.

Description

Channel state information feedback method and device

The present application claims priority of chinese patent application with application number 201910239396.8 entitled "a method and apparatus for feeding back channel state information" filed by chinese patent office on 27/3/2019, the entire contents of which are incorporated herein by reference.

Technical Field

The present application relates to the field of wireless communication technologies, and in particular, to a method and an apparatus for feeding back channel state information.

Background

In the NR Rel-15 system, a type ii (typeii) codebook is defined that supports both the rank1 codebook and the rank2 codebook based on the way in which beams within the orthogonal beam group are linearly combined.

For one subband, the rank1 codebook is expressed as:

for one subband, the rank2 codebook is expressed as:

wherein the content of the first and second substances,

l represents the number of orthogonal beams within the group,

represents orthogonal beams, which employ 2D DFT (two-dimensional discrete fourier transform) vectors; r-0, 1 denotes the first and second polarization directions in the dual-polarized antenna array, l-0, 1 denotes a layer.

Representing the broadband amplitude coefficients acting on the beam i, the polarization direction r and the layer l in the beam group;

representing subband magnitude coefficients acting on a beam i, the polarization direction r and the layer l in a beam group；c_r,l,iThe subband phase coefficients acting on the beam i, the polarization direction r and the layer l in the beam group are shown.

Since the number of codebook coefficients of Rank2 is about one time of the number of codebook coefficients of Rank1, the overhead of codebooks with different values of Rank Indication (RI) is very different. When the base station receives Channel State Information (CSI) fed back by the terminal, the base station cannot know the value of the RI before correctly decoding, and thus cannot determine the overhead of the CSI. In order to avoid that the base station cannot correctly perform CSI decoding due to overhead ambiguity, in Rel-15, a two-part structure is adopted for reporting Type II CSI. The first part of the CSI comprises: RI, a wideband Quality Indicator (CQI) corresponding to a first codeword (codeword), a differential CQI corresponding to the first codeword (codeword), the number of zero coefficients in layer one, and the number of zero coefficients in layer two; the second part of the CSI comprises: the antenna comprises a rotation factor, beam indication information, a strongest beam indication of a layer one, a wideband amplitude coefficient of a layer one, a strongest beam indication of a layer two, a wideband amplitude coefficient of a layer two, at least one of a subband phase and a subband amplitude coefficient of an even subband, and at least one of a subband phase and a subband amplitude coefficient of an odd subband. The overhead of the first part of the CSI is fixed and is irrelevant to the value of the RI, and the overhead of the second part of the CSI can be determined by the result of decoding of the first part.

Since the feedback for each subband includes both subband phase coefficients and subband amplitude coefficients, the feedback overhead required to feedback the coefficients for all subbands is large when the number of subbands is large. A low-overhead TypeII codebook is defined in the NR Rel-16 system, the coefficient of each sub-band is compressed, and the compressed differential amplitude coefficient, phase coefficient and reference amplitude coefficient are all fed back to a base station.

At present, no corresponding CSI feedback method exists for the code book structure of Rel-16 and the fed-back CSI information.

Disclosure of Invention

The embodiment of the application provides a channel state information feedback method and device.

In a first aspect, a channel state information feedback method is provided, where the method includes:

the terminal performs channel measurement to obtain a coefficient set for feedback, and sends Channel State Information (CSI) to the network device. The CSI includes the coefficient set and information indicating a strongest amplitude coefficient, where the information indicating the strongest amplitude coefficient is used to indicate a strongest amplitude coefficient of at least one layer. The coefficient set comprises at least one layer of amplitude coefficient set and phase coefficient set, the amplitude coefficient set comprises differential amplitude coefficients and reference amplitude coefficients, and the coefficient set is used for constructing a precoding matrix.

In a possible implementation manner, the indication information of the strongest amplitude coefficient includes an index of the strongest amplitude coefficient of at least one layer; the number of bits occupied by the index of the strongest amplitude coefficient of the at least one layer is determined by the maximum value of the number of nonzero coefficients of each layer which allows feedback, or is determined by the maximum value of the number of nonzero coefficients of all layers which allow feedback and/or the number of feedback layers, or is determined by the total number of nonzero coefficients of all layers which allow feedback and/or the number of feedback layers, wherein the maximum value of the number of nonzero coefficients which allow feedback is predefined by a system or configured to the terminal by network equipment.

In a possible implementation manner, the indication information of the strongest amplitude coefficient of each of the at least one layer includes first indication information corresponding to the corresponding layer, where the first indication information is used to indicate an index of the strongest amplitude coefficient of the corresponding layer; or the indication information of the strongest amplitude coefficient includes second indication information, where the second indication information is used to indicate the index of the strongest amplitude coefficient of the at least one layer, and different values of the second indication information indicate different combinations of the indexes of the strongest amplitude coefficients of the at least one layer.

In a possible implementation manner, the CSI further includes quantity indication information of non-zero coefficients of at least one layer, and position indication information of non-zero coefficients of at least one layer; wherein the non-zero coefficients include non-zero differential amplitude coefficients, and the position indication information of the non-zero coefficients of the at least one layer is used to indicate the positions of the non-zero coefficients of the at least one layer in the coefficient sets of the respective layers used to construct the precoding matrix.

Optionally, the position indication information of the non-zero coefficient of the at least one layer is represented by a bit sequence including at least N bits, and a value of N is determined according to a value of the reference amplitude coefficient of the at least one layer.

Optionally, if the value of the reference amplitude coefficient is not zero, N — 2L × M; if the values of the reference amplitude coefficients are all zero, N is L M; where L denotes the number of orthogonal beams in the orthogonal beam group used to construct the precoding matrix, and M denotes the number of basis vectors used to construct the precoding matrix.

In a possible implementation manner, if the weak polarization indication information indicates that all values of the differential amplitude coefficients in one polarization direction of the at least one layer are all zero, the CSI does not include the reference amplitude coefficient or the reference amplitude coefficient set of the at least one layer. Optionally, the CSI further includes polarization direction indication information, which is used to indicate a polarization direction in which all differential amplitude coefficients in the two polarization directions take a value of zero.

Optionally, if the weak polarization indication information indicates that all differential amplitude coefficient values in one polarization direction of the at least one layer include a non-zero value, N is 2L × M; and if the weak polarization indication information indicates that all the differential amplitude coefficient values of one polarization direction of the at least one layer are all zero, then N is equal to L. Where L denotes the number of orthogonal beams in the orthogonal beam group used to construct the precoding matrix, and M denotes the number of basis vectors used to construct the precoding matrix.

In a possible implementation manner, the position indication information of the non-zero coefficient of each layer in at least one layer is indicated by using first indication information, and the first indication information indicates the position of the non-zero coefficient of the corresponding layer in a coefficient set of the layer used for constructing the precoding matrix; or indicating the position indication information of the nonzero coefficient of at least one layer by using second indication information, wherein different values of the second indication information indicate different combinations of the positions of the nonzero coefficients of at least one layer.

In one possible implementation, the CSI includes a first part and a second part. The first part of the CSI comprises: a reference amplitude coefficient set of each layer, and quantity indication information of non-zero coefficients of each layer; the second part of the CSI comprises: the precoding matrix comprises a differential amplitude coefficient set and a phase coefficient set of each layer, indication information of the strongest amplitude coefficient of each layer, and position indication information of a non-zero coefficient of each layer, wherein the position indication information of the non-zero coefficient of each layer is used for indicating the position of the non-zero coefficient of each layer in the coefficient set of the corresponding layer for constructing the precoding matrix.

In one possible implementation, the CSI includes a first part and a second part. The first part of the CSI comprises: information indicative of a total number of non-zero coefficients for all layers; the bit number occupied by the indication information of the total number of the nonzero coefficients of all the layers is determined according to the maximum value of the number of the nonzero coefficients allowed to be fed back by each layer, or is determined according to the maximum value of the total number of the nonzero coefficients allowed to be fed back by all the layers; the second part of the CSI comprises: the precoding matrix comprises a reference amplitude coefficient set, a differential amplitude coefficient set and a phase coefficient set of each layer, indication information of a strongest amplitude coefficient of each layer or combination indication information of the strongest amplitude coefficients of all layers, and position indication information of a non-zero coefficient of each layer, wherein the position indication information of the non-zero coefficient of each layer is used for indicating the position of the non-zero coefficient of each layer in the coefficient set of the corresponding layer used for constructing the precoding matrix.

In one possible implementation, the first portion of CSI further comprises at least one of a Rank Indication (RI), a wideband Channel Quality Indication (CQI), and a differential COI; the second portion of the CSI further comprises: at least one of a beam index, a basis vector index.

In a second aspect, a channel state information feedback method is provided, including: the network equipment receives CSI sent by a terminal and constructs a precoding matrix corresponding to the terminal according to the CSI. The CSI comprises a coefficient set used for constructing a precoding matrix and indication information comprising a strongest amplitude coefficient, wherein the coefficient set comprises an amplitude coefficient set and a phase coefficient set of at least one layer, the amplitude coefficient set comprises a differential amplitude coefficient and a reference amplitude coefficient, and the indication information of the strongest amplitude coefficient is used for indicating the strongest amplitude coefficient of at least one layer.

In a possible implementation manner, the indication information of the strongest amplitude coefficient of the at least one layer includes first indication information corresponding to the corresponding layer, where the first indication information is used to indicate an index of the strongest amplitude coefficient of the corresponding layer; or the indication information of the strongest amplitude coefficient includes second indication information, where the second indication information is used to indicate the index of the strongest amplitude coefficient of the at least one layer, and different values of the second indication information indicate different combinations of the indexes of the strongest amplitude coefficients of the at least one layer.

In a possible implementation manner, if the weak polarization indication information indicates that all values of the differential amplitude coefficients in one polarization direction of the at least one layer are all zero, the CSI does not include the reference amplitude coefficient or the reference amplitude coefficient set of the at least one layer. Optionally, the CSI includes polarization direction indication information, which is used to indicate a polarization direction in which all differential amplitude coefficients in the two polarization directions take a value of zero.

In one possible implementation, the first part of the CSI further includes at least one of RI, wideband CQI, and differential COI; the second portion of the CSI further comprises: at least one of a beam index, a basis vector index.

In a third aspect, a terminal is provided, including: the processing module is used for carrying out channel measurement to obtain a coefficient set for feedback, the coefficient set comprises at least one layer of amplitude coefficient set and phase coefficient set, the amplitude coefficient set comprises a differential amplitude coefficient and a reference amplitude coefficient, and the coefficient set is used for constructing a precoding matrix. And the sending module is used for sending Channel State Information (CSI) to network equipment, wherein the CSI comprises the coefficient set and the indication information of the strongest amplitude coefficient, and the indication information of the strongest amplitude coefficient is used for indicating the strongest amplitude coefficient of at least one layer.

In a fourth aspect, a network device is provided, comprising: the terminal comprises a receiving module and a processing module, wherein the receiving module is used for receiving CSI sent by the terminal, the CSI comprises a coefficient set which is measured by the terminal and used for constructing a precoding matrix and indication information comprising a strongest amplitude coefficient, the coefficient set comprises an amplitude coefficient set and a phase coefficient set of at least one layer, the amplitude coefficient set comprises a differential amplitude coefficient and a reference amplitude coefficient, and the indication information of the strongest amplitude coefficient is used for indicating the strongest amplitude coefficient of at least one layer. And the processing module is used for constructing a precoding matrix corresponding to the terminal according to the CSI.

In a fifth aspect, a communication apparatus is provided, including: a processor, memory, transceiver; the processor is configured to read computer instructions in the memory and execute the method according to any one of the above first aspects.

In a sixth aspect, a communication apparatus is provided, including: a processor, memory, transceiver; the processor is configured to read the computer instructions in the memory and execute the method according to any one of the above sixth aspects.

In a seventh aspect, there is provided a computer-readable storage medium having stored thereon computer-executable instructions for causing the computer to perform the method of any of the above first aspects.

In an eighth aspect, there is provided a computer-readable storage medium having stored thereon computer-executable instructions for causing the computer to perform the method of any of the second aspects above.

In the above embodiment of the present application, a terminal performs channel measurement to obtain a coefficient set for feedback, and then performs CSI feedback, where the fed back CSI includes the coefficient set and indication information of a strongest amplitude coefficient, where the coefficient set includes at least one layer of amplitude coefficient set and a phase coefficient set, and the amplitude coefficient set includes a differential amplitude coefficient and a reference amplitude coefficient, so as to implement CSI feedback for a codebook type in which an amplitude coefficient used for constructing a precoding matrix includes a reference amplitude coefficient, and thus, a network device may construct a precoding matrix of a corresponding type according to the CSI fed back by the terminal.

Drawings

Fig. 1 is a schematic diagram of a CSI feedback process implemented by a terminal side according to an embodiment of the present application;

fig. 2 is a schematic view of a CSI feedback process implemented by a network device side according to an embodiment of the present application;

fig. 3 is a schematic structural diagram of a terminal according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of a network device according to an embodiment of the present application;

fig. 5 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 6 is a schematic structural diagram of a communication device according to another embodiment of the present application.

Detailed Description

In the NR Rel-16 system, a low-overhead Type II codebook is defined, the coefficient of each sub-band is compressed, and the compressed coefficient is fed back to a base station. Taking rank1 as an example, the codebook may be expressed as shown in the following equation (3) for all subbands:

wherein:

W₁the method comprises the steps of including orthogonal combined beams, wherein the included orthogonal combined beams are the same as a Type II codebook of a Rel-15 system;

representing the compressed coefficient, where p_diff(i, j) represents a differential amplitude coefficient, q (i, j) represents a phase coefficient, p_refRepresenting a reference amplitude coefficient. The reference amplitude coefficient may be quantized to 4 bits, which take the value of

If it is

Is located in the first polarization direction (i.e. the strongest amplitude coefficient of (b) is located in the first polarization direction

The first L rows) of the first row, the reference amplitude coefficient is located in the second polarization direction, as shown in the above expression; if it is

Is located in the second polarization direction (i.e. the strongest amplitude coefficient of (b) is located in the second polarization direction

The last L rows) of the array, the reference amplitude coefficient is located in the first polarization direction. The differential amplitude coefficient, the phase coefficient and the reference amplitude coefficient are all required to be fed back to the base station. And the terminal also needs to report the position of the strongest amplitude coefficient. The differential amplitude coefficient corresponding to the strongest amplitude coefficient is defined as 1, and the phase coefficient corresponding to the strongest amplitude coefficient is defined as 0, so that the differential amplitude coefficient and the phase coefficient corresponding to the strongest amplitude coefficient do not need to be reported. In addition, each layer is provided in view of further saving feedback overhead

The compression coefficients in (1) do not need to be reported completely, and only the nonzero coefficients in (1) can be reported. For Rank1 and Rank2, the base station configures the upper limit of the number of nonzero coefficients reported by each layer to be K0. Since all the compression coefficients do not need to be reported, the position of the reported nonzero coefficient needs to be indicated for each layer.

W_fRepresenting compressed basis vectors, comprising M basis vectors, each of length N₃，N₃Determined by the number of CQI subbands configured by the system.

Taking rank2 as an example, the Type II codebook in the NR Rel-16 system has the first-layer precoding expressed as the following formula (4):

the second layer precoding is expressed as the following equation (5):

wherein, W₁The method comprises the steps of including orthogonal combined beams, wherein the number of the included orthogonal beams is 2L; w_f,0A base vector, W, representing layer one_f,1A base vector, W, representing layer two_f,0And W_f,1Respectively comprises M base vectors;

represents the layer-one corresponding compressed coefficients,

representing the compressed coefficients corresponding to layer two,

and

each of which contains 2L x M coefficients.

In the case of other rank values, the expression of the Type II codebook in the NR Rel-16 system can be obtained by referring to the above equations (4) and (5), and details are not repeated here.

At present, no corresponding CSI feedback method exists for a codebook structure of Rel-16 and CSI to be reported.

In view of the above problems, embodiments of the present application provide a CSI feedback method and apparatus, which can implement CSI feedback for a codebook type including a reference amplitude coefficient in an amplitude coefficient used for constructing a precoding matrix, so that a network device can construct a precoding matrix of a corresponding type according to CSI fed back by a terminal. The embodiment of the application is applicable to the Rel-16 system and performs CSI feedback based on the type II codebook structure.

Some technical terms in the embodiments of the present application will be described first.

In this embodiment, a "terminal," also referred to as User Equipment (UE), a Mobile Station (MS), a Mobile Terminal (MT), etc., is a device that provides voice and/or data connectivity to a user, for example, a handheld device, a vehicle-mounted device, etc. with a wireless connection function. Currently, some examples of terminals are: a mobile phone (mobile phone), a tablet computer, a notebook computer, a palm top computer, a Mobile Internet Device (MID), a wearable device, a Virtual Reality (VR) device, an Augmented Reality (AR) device, a wireless terminal in industrial control (industrial control), a wireless terminal in self driving (self driving), a wireless terminal in remote surgery (remote medical supply), a wireless terminal in smart grid (smart grid), a wireless terminal in transportation safety (smart security), a wireless terminal in city (smart city), a wireless terminal in home (smart home), and the like.

The "network device" in the embodiment of the present application may be a RAN node or a base station. The RAN is the part of the network that accesses the terminal to the wireless network. A RAN node (or device) is a node (or device) in a radio access network, which may also be referred to as a base station. Currently, some examples of RAN nodes are: a gbb, a Transmission Reception Point (TRP), an evolved Node B (eNB), a Radio Network Controller (RNC), a Node B (NB), a Base Station Controller (BSC), a Base Transceiver Station (BTS), a home base station (e.g., home evolved Node B, or home Node B, HNB), a Base Band Unit (BBU), or a wireless fidelity (Wifi) Access Point (AP), etc. In addition, in one network configuration, the RAN may include a Centralized Unit (CU) node and a Distributed Unit (DU) node.

The codebook in the embodiment of the present application is a matrix, for example, the codebook is a precoding matrix.

The "beams," i.e., vectors, in the embodiments of the present application may be referred to as beam vectors or otherwise named.

The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

Referring to fig. 1, a schematic diagram of a CSI feedback process implemented on a terminal side according to an embodiment of the present application is provided, where the process may include:

s101: and the terminal carries out channel measurement to obtain a coefficient set for feedback, wherein the coefficient set is used for constructing a precoding matrix.

The coefficient set comprises an amplitude coefficient set and a phase coefficient set of at least one layer, and the amplitude coefficient set comprises a differential amplitude coefficient and a reference amplitude coefficient.

The coefficients in the coefficient set for feedback may be quantized or compressed coefficients to reduce the feedback overhead.

S102: and the terminal sends CSI to the network equipment, wherein the CSI comprises the coefficient set and the indication information of the strongest amplitude coefficient.

For a certain layer, the strongest amplitude coefficient refers to the difference amplitude coefficient with the largest value in the difference amplitude coefficient set of the layer. The difference amplitude coefficient with the largest value can be quantized to 1. When CSI feedback is performed, the strongest amplitude coefficient may or may not be reported.

Wherein the indication information of the strongest amplitude coefficient is used for indicating the strongest amplitude coefficient of at least one layer. Specifically, for a certain layer, the indication information of the strongest amplitude coefficient is used to indicate the position of the strongest amplitude coefficient of the layer in a coefficient set used for constructing a precoding matrix, where the coefficient set refers to a coefficient set corresponding to the layer. For example, the indication information of the strongest amplitude coefficient of the layer one indicates the position of the strongest amplitude coefficient in the coefficient matrix corresponding to the layer one for constructing the precoding matrix, and the indication information of the strongest amplitude coefficient of the layer two indicates the position of the strongest amplitude coefficient in the coefficient matrix corresponding to the layer two for constructing the precoding matrix. Taking the codebook in which rank is 2 as shown in the above equations (4) and (5) as an example, the index of the strongest amplitude coefficient of layer one is used to indicate that the strongest amplitude coefficient of layer one is in equation (4)

(i.e., the coefficient matrix for layer one), the index of the strongest amplitude coefficient for layer two is used to indicate the strongest amplitude coefficient for layer two in equation (5)

(i.e., the coefficient matrix for layer two).

Optionally, based on the flow shown in fig. 1, in some embodiments, if the value of RI used for feedback is equal to 1 (i.e., rank is 1), the coefficient set includes an amplitude coefficient set and a phase coefficient set of layer one, and information indicating the strongest amplitude coefficient of layer one; if the value of RI used for feedback is equal to 2 (i.e., rank is 2), the coefficient set includes an amplitude coefficient set and a phase set of layer one and indication information of the strongest amplitude coefficient of layer one, and also includes an amplitude coefficient set and a phase set of layer two and indication information of the strongest amplitude coefficient of layer two. And if the value of the RI used for feedback is an integer larger than 2, feeding back the amplitude coefficient set and the phase coefficient set of the layer and the indication information of the strongest amplitude coefficient of the layer aiming at each layer.

Optionally, based on the procedure shown in fig. 1, in some embodiments, the CSI fed back by the terminal further includes zero indication information of the reference amplitude coefficient of at least one layer, where the zero indication information is used to indicate whether a value of the reference amplitude coefficient of the at least one layer is zero. If the zero indication information of the reference amplitude coefficient of the first layer indicates that the value of the reference amplitude coefficient of the first layer is zero, the CSI does not include the reference amplitude coefficient set of the first layer. Wherein the first layer is any one of the at least one layer. Taking rank2 as an example, the CSI fed back by the terminal includes zero indication information of the reference amplitude coefficient of the layer one, and the zero indication information indicates that the value of the reference amplitude coefficient of the layer one is zero, so that the fed back CSI does not include the reference amplitude coefficient set of the layer one.

Optionally, based on the procedure shown in fig. 1, in some embodiments, the CSI fed back by the terminal further includes at least one layer of weak polarization indication information, which is used to indicate that all differential amplitude coefficient values of one polarization direction of the at least one layer are all zero. If the weak polarization indication information indicates that all differential amplitude coefficient values in one polarization direction of the at least one layer are all zero, the CSI does not include the reference amplitude coefficient or the reference amplitude coefficient set of the at least one layer. For example, if the weak polarization indication information of the first layer indicates that all the differential amplitude coefficients of one polarization direction of the first layer are zero, the CSI does not include the reference amplitude coefficient of the first layer. Wherein the first layer is any one of the at least one layer. Taking rank-2 as an example, the CSI fed back by the terminal includes weak polarization indication information of the layer one, where the weak polarization indication information indicates that all values of the differential amplitude coefficients in one polarization direction of the layer one are all zero, and therefore the fed back CSI does not include the reference amplitude coefficient of the layer one. Further, if the weak polarization indication information indicates that all the differential amplitude coefficient values in one polarization direction of the at least one layer include non-zero values, the processing may be performed in a manner described in other embodiments in this application.

Optionally, based on the process shown in fig. 1, in some embodiments, the CSI fed back by the terminal further includes at least one layer of weak polarization indication information, which is used to indicate that all values of all differential amplitude coefficients of one polarization direction of the at least one layer are all zero, and if the weak polarization indication information indicates that all values of all differential amplitude coefficients of one polarization direction of the at least one layer are all zero, the CSI does not include the reference amplitude coefficient or the reference amplitude coefficient set of the at least one layer, and the CSI includes polarization direction indication information, which is used to indicate a polarization direction in which all values of the differential amplitude coefficients of two polarization directions are zero. Alternatively, the polarization direction indication information may be 1-bit indication information. For example, if the weak polarization indication information of the first layer indicates that all the differential amplitude coefficients of one polarization direction of the first layer are all zero, the CSI does not include the reference amplitude coefficient of the first layer, and meanwhile, the CSI further includes 1-bit polarization direction indication information for indicating that one of the two polarization directions is weak polarization, that is, the 1-bit polarization direction indication information is used to indicate the polarization direction in which all the differential amplitude coefficients of the two polarization directions take values of zero. Wherein the first layer is any one of the at least one layer. Taking rank2 as an example, the CSI fed back by the terminal includes weak polarization indication information of the layer one, where the weak polarization indication information indicates that all values of the differential amplitude coefficients in a certain polarization direction of the layer one are all zero, and therefore the fed back CSI does not include the reference amplitude coefficient of the layer one. Meanwhile, the fed back CSI includes 1-bit polarization direction indication information, which indicates that the weak polarization of the layer one is the second polarization direction, that is, all the differential amplitude coefficients of the second polarization direction of the layer one are indicated to be all zero, or the polarization direction in which all the differential amplitude coefficients of the two polarization directions of the layer one are zero is indicated to be the second polarization direction. Further, if the weak polarization indication information indicates that all the differential amplitude coefficient values in one polarization direction of the at least one layer include non-zero values, the processing may be performed in a manner described in other embodiments in this application.

Optionally, based on the flow shown in fig. 1, in some embodiments, the CSI further includes at least one of RI, wideband CQI, and differential COI; and, the CSI further comprises: at least one of a beam index, a basis vector index of at least one layer.

Alternatively, based on the flow shown in fig. 1, the indication information of the strongest amplitude coefficient may be an index of the strongest amplitude coefficient, or may be other indication information capable of indicating the index of the strongest amplitude coefficient.

Optionally, based on the flow shown in fig. 1, in some embodiments, the indication information of the strongest amplitude coefficient may be single-layer independent indication information or multi-layer joint indication information. Namely, the index of the strongest amplitude coefficient can adopt single-layer independent indication or multi-layer joint indication. And a multi-layer joint indication mode is adopted, so that the feedback overhead can be reduced.

Specifically, in an example of using single-layer independent indication, the indication information of the strongest amplitude coefficient of each of the at least one layer includes first indication information (the first indication information may also be referred to as independent indication information) corresponding to the corresponding layer, and the first indication information is used for indicating an index of the strongest amplitude coefficient of the corresponding layer. Taking rank as 2 as an example, the CSI fed back by the terminal includes an index of the strongest amplitude coefficient of layer one and an index of the strongest amplitude coefficient of layer two.

In an example that a multi-layer joint indication is adopted, the indication information of the strongest amplitude coefficient includes second indication information (the second indication information may also be referred to as joint indication information), the second indication information is used for indicating an index of the strongest amplitude coefficient of the at least one layer, and different values of the second indication information indicate different combinations of indexes of the strongest amplitude coefficients of the at least one layer. Taking rank2 as an example, the CSI fed back by the terminal includes a joint indication information, and the joint indication information indicates the index of the strongest amplitude coefficient of layer one and the index of the strongest amplitude coefficient of layer two at the same time. Optionally, when the strongest amplitude coefficient index of each layer of the multi-layer joint indication is adopted, the bit number occupied by the joint indication information is at least equal to

Wherein, K₀Represents the maximum value of the number of non-zero coefficients that the terminal is allowed to feedback,

is a number of combinations whose value represents the selection of j (j) from the i numbers<I) number of all possible cases.

Wherein the non-zero coefficient comprises a non-zero differential amplitude coefficient, and further comprises a non-zero reference amplitude coefficient.

Optionally, based on the procedure shown in fig. 1, in some embodiments, if the indication information of the strongest amplitude coefficient includes an index of the strongest amplitude coefficient of at least one layer, the number of bits occupied by the index of the strongest amplitude coefficient of the at least one layer is determined by a maximum value of the number of non-zero coefficients of each layer that allows feedback, or is determined by at least one of the maximum value of the number of non-zero coefficients of all layers that allow feedback, the number of feedback layers, or is determined by at least one of the total number of non-zero coefficients of all layers that the terminal feeds back, and the number of feedback layers, where the maximum value of the number of non-zero coefficients that allows feedback is predefined by a system or configured to the terminal by a network device.

Taking rank2 as an example, in one example, the maximum number of non-zero coefficients of each layer that the terminal is allowed to feedback is K₀The number of bits occupied by the index of the strongest amplitude coefficient corresponding to each layer is at least log₂(K₀) A plurality of; in another example, the number of non-zero coefficients of all layers fed back by the terminal is K₁The number of bits occupied by the index of the strongest amplitude coefficient corresponding to each layer is at least log₂(K₁) And (4) respectively.

Since the number of bits occupied by the index of the strongest amplitude coefficient of each layer is determined by the maximum value of the number of non-zero coefficients allowed to be fed back, and the maximum value of the number of non-zero coefficients allowed to be fed back is determined or known for the terminal and the network device, the network device can determine the number of bits occupied by the index of the strongest amplitude coefficient of each layer, and can further correctly resolve the index of the strongest amplitude coefficient. The number of bits occupied by the index of the strongest amplitude coefficient of each layer may also be determined by the total number of nonzero coefficients of all layers fed back by the terminal and the number of feedback layers, and the total number of nonzero coefficients of all layers fed back by the terminal and the number of feedback layers may be included in the first part of the CSI.

Optionally, based on the procedure shown in fig. 1, in some embodiments, the CSI fed back by the terminal further includes information indicating the number of non-zero coefficients of at least one layer, and information indicating the position of the non-zero coefficients of at least one layer. Wherein the position indication information of the non-zero coefficient of the at least one layer is used for indicating the position of the non-zero coefficient of the at least one layer in a coefficient set (such as a coefficient matrix) for constructing a precoding matrix. The coefficient matrix is a coefficient matrix of the corresponding layer.

Taking the precoding with rank2 as an example,the CSI fed back by the terminal comprises position indication information of a non-zero coefficient of a layer I and position indication information of a non-zero coefficient of a layer II. Wherein, the position indication information of the non-zero coefficient of the layer one is used for indicating that the non-zero coefficient of the layer one is in the formula (4)

Position indication information of the non-zero coefficient of layer two for indicating that the non-zero coefficient of layer two is in the formula (5)

Of (c) is used.

Alternatively, the position indication information of the non-zero coefficient may adopt a bit sequence (or bit bitmap), or its index may be indicated by a combination number.

Optionally, the position indication information of the non-zero coefficient of the at least one layer is represented by a bit sequence including at least N bits, and a value of the N is determined according to a value of the reference amplitude coefficient of the at least one layer. Specifically, in one possible implementation, if the value of the reference amplitude coefficient is not zero, N is 2L × M; and if the reference amplitude coefficient is zero, N is L M. Where L denotes the number of orthogonal beams in the orthogonal beam group used to construct the precoding matrix, and M denotes the number of basis vectors used to construct the precoding matrix.

Optionally, in some embodiments of the present application, the position indication information of the non-zero coefficient may be indicated independently for each layer, or may be indicated jointly by multiple layers. And a multi-layer joint indication mode is adopted, so that the feedback overhead can be reduced.

In an example of independent indication for each layer, the position indication information of the non-zero coefficient of each layer in at least one layer is indicated using first indication information (also referred to as independent indication information) indicating the position of the non-zero coefficient of the corresponding layer in the coefficient set of the layer used for constructing the precoding matrix. Taking rank-2 as an example, the CSI fed back by the terminal includes position indication information (e.g., bit sequence 1) of the non-zero coefficient of layer one and position indication information (e.g., bit sequence 2) of the non-zero coefficient of layer two.

In an example of multi-layer joint indication, position indication information of non-zero coefficients of at least one layer is indicated by using second indication information (also referred to as joint indication information), and different values of the second indication information indicate different combinations of non-zero coefficient positions of the at least one layer. Optionally, the number of bits occupied by the joint indication information is determined by a sum of a total number of compressed coefficients including a zero coefficient and a total number of non-zero coefficients.

Optionally, according to the flow shown in fig. 1, in some embodiments, in the CSI fed back by the terminal, the amplitude coefficient set includes a reference amplitude coefficient set and a differential amplitude coefficient set, and the CSI includes a first part and a second part. The first part of the CSI comprises: a set of reference amplitude coefficients for each layer, and a number of non-zero coefficients for each layer. The second part of the CSI comprises: the precoding matrix comprises a differential amplitude coefficient set and a phase coefficient set of each layer, indication information of the strongest amplitude coefficient of each layer, and position indication information of a non-zero coefficient of each layer, wherein the position indication information of the non-zero coefficient of each layer is used for indicating the position of the non-zero coefficient of each layer in the coefficient set of the corresponding layer for constructing the precoding matrix.

Optionally, according to the procedure shown in fig. 1, in some embodiments, the CSI includes a first part and a second part, and the first part of the CSI includes: information indicative of a total number of non-zero coefficients for all layers; the number of bits occupied by the indication information of the total number of nonzero coefficients of all layers is determined according to the maximum value of the number of nonzero coefficients allowed to be fed back by each layer, or determined according to the maximum value of the total number of nonzero coefficients allowed to be fed back by all layers. The second part of the CSI comprises: the precoding matrix comprises a reference amplitude coefficient set, a differential amplitude coefficient set and a phase coefficient set of each layer, indication information of a strongest amplitude coefficient of each layer, and position indication information of a non-zero coefficient of each layer, wherein the position indication information of the non-zero coefficient of each layer is used for indicating the position of the non-zero coefficient of each layer in the coefficient set of the corresponding layer used for constructing the precoding matrix. In another example, the "indication information of the strongest amplitude coefficient per layer" in the CSI second part may also be replaced by the combined indication information of the strongest amplitude coefficients of all layers.

As can be seen from the above description, the terminal performs CSI feedback after performing channel measurement to obtain a coefficient set for feedback, where the fed back CSI includes the coefficient set and indication information of a strongest amplitude coefficient, where the coefficient set includes at least one layer of amplitude coefficient set and phase coefficient set, and the amplitude coefficient set includes a differential amplitude coefficient and a reference amplitude coefficient, so as to implement CSI feedback for a codebook type in which an amplitude coefficient used for constructing a precoding matrix includes a reference amplitude coefficient, and thus, a network device may construct a precoding matrix of a corresponding type according to the CSI fed back by the terminal. Further, by adopting the above embodiment of the present application, feedback overhead can also be saved.

Referring to fig. 2, a schematic diagram of a CSI feedback process implemented on a network device side according to an embodiment of the present application is provided, where the process may include:

s201: the method comprises the steps that network equipment receives CSI sent by a terminal, wherein the CSI comprises a coefficient set which is measured by the terminal and used for constructing a precoding matrix and indication information comprising a strongest amplitude coefficient, the coefficient set comprises an amplitude coefficient set and a phase coefficient set of at least one layer, the amplitude coefficient set comprises a differential amplitude coefficient and a reference amplitude coefficient, the coefficient set is used for constructing the precoding matrix, and the indication information of the strongest amplitude coefficient is used for indicating the strongest amplitude coefficient of at least one layer.

For the content included in the CSI and the method for the terminal to feed back the CSI, reference may be made to the foregoing embodiments, which are not described herein again.

S202: and the network equipment constructs a precoding matrix corresponding to the terminal according to the CSI.

For example, the first part of the CSI received by the network device includes: the total number of non-zero coefficients of RI, layer one and layer two indicates information. The second part of the CSI received by the network equipment comprises: the beam index, the base vector index of layer one, the position indication information of the non-zero coefficients of layer one, the index of the strongest amplitude coefficient of layer one, the reference amplitude coefficient, the differential amplitude coefficient, and the phase amplitude coefficient of layer one, and the base vector index of layer two, the position indication information of the non-zero coefficients of layer two, the index of the strongest amplitude coefficient of layer two, the reference amplitude coefficient, the differential amplitude coefficient, and the phase amplitude coefficient of layer two.

Taking rank indicated by RI as an example 2, the network device determines the coefficient matrix of layer one according to the position indication information of the nonzero coefficient of layer one, the index of the strongest amplitude coefficient of layer one, the reference amplitude coefficient, the differential amplitude coefficient and the phase amplitude coefficient of layer one, and the total number indication information of the nonzero coefficients of layer one and layer two; and the network equipment calculates to obtain the precoding matrix of the layer one according to the coefficient matrix of the layer one, the beam indicated by the beam index and the base vector indicated by the base vector index of the layer one.

The network equipment determines a coefficient matrix of the layer two according to position indication information of the nonzero coefficient of the layer two, an index of the strongest amplitude coefficient of the layer two, a reference amplitude coefficient, a differential amplitude coefficient and a phase amplitude coefficient of the layer two and total quantity indication information of the nonzero coefficients of the layer one and the layer two; and the network equipment calculates to obtain a precoding matrix of the layer two according to the coefficient matrix of the layer two, the beam indicated by the beam index and the base vector indicated by the base vector index of the layer two.

In order to more clearly understand the above embodiments of the present application, the following detailed description is given with reference to specific examples, according to any embodiment or combination of multiple embodiments described above.

Example 1

The system convention is as follows: for each layer, the precoding matrix uses 2L beams and forms a set of compressed basis vectors using M basis vectors. For each layer, the terminal reports K at most₀A non-zero coefficient (where K₀<2L × M). For the Type II codebook with rank1, its precoding is expressed as the following equation (6):

wherein, W₁In which 2L beams, W_fComprises a plurality of M basis vectors, wherein the M basis vectors,

contains 2L M coefficients.

And at the terminal side, the terminal performs channel measurement, obtains the CSI required to be fed back based on the measurement result, and feeds back the CSI to the base station. The CSI fed back by the terminal includes a first part and a second part.

Wherein the CSI first part comprises:

RI；

a wideband CQI;

a differential CQI;

a reference amplitude coefficient for layer one; optionally, the terminal may report only the non-zero reference amplitude coefficient of layer one;

number of non-zero coefficients of layer one indicates information;

a reference amplitude coefficient for layer two; here, since rank is 1, the reference amplitude coefficient of layer two is zero;

the number of non-zero coefficients of layer two indicates information, where the non-zero coefficients include non-zero reference amplitude coefficients and non-zero differential amplitude coefficients. Here, since rank is 1, the number indicated by the number-of-non-zero coefficients indication information of layer two is zero.

The CSI second part includes:

a beam index indicating orthogonal beams used to construct a precoding matrix;

the base vector index of the layer one indicates a base vector corresponding to the layer one for constructing the precoding matrix;

position indication information of non-zero coefficients of layer one for indicating that the non-zero reference amplitude coefficients are in a coefficient matrix corresponding to layer one for constructing the precoding matrix (i.e., in equation 6)

) The position of (1);

the index of the strongest amplitude coefficient of layer one indicates the coefficient matrix corresponding to the strongest amplitude coefficient of layer one in layer one for constructing the precoding matrix (i.e., in equation 6)

) The position of (1);

a differential amplitude coefficient of layer one;

phase amplitude coefficient of layer one.

Optionally, taking a maximum value of rank as 2 as an example, in order to ensure that overhead of the first part of the CSI is constant, the first part of the CSI includes a reserved first information unit and a reserved second information unit, and lengths of the first information unit and the second information unit are fixed, where the first information unit is used to carry a reference amplitude coefficient of the second layer, and the second information unit is used to carry quantity indication information of a nonzero coefficient of the second layer. When the RI fed back by the terminal is 1, the value of the first information element (i.e., the reference amplitude coefficient of layer two) in the first part of the CSI is zero, and the value of the second information element (i.e., the number indication information of the non-zero coefficient of layer two) is also zero.

Optionally, in example 1, if the reference amplitude coefficient of the layer one is not zero, it is described that both polarization directions of the layer one include the differential amplitude coefficient to be reported, and at this time, the bit bitmap (or referred to as bit sequence) used by the position indication information of the nonzero coefficient includes 2L × M bits; if the reference amplitude coefficient of the layer one takes a value of zero, it is described that only one polarization direction of the layer one contains the differential amplitude coefficient to be reported, and at this time, the bit bitmap (or bit sequence) used by the position indication information of the non-zero coefficient of the layer one only needs to indicate the coefficient position of one polarization direction, so that the adopted bit bitmap (or bit sequence) contains L × M bits.

Example 2

For each layer, the base station configures a precoding matrix using 2L beams, and forms a compressed base vector set using M base vectors. For each layer, the terminal reports K at most₀A non-zero coefficient (where K0<2L × M). For the Type II codebook with rank2, its first layer precoding is represented by the following equation (7):

the second layer precoding is expressed as the following equation (8):

wherein, W₁In which 2L beams, W_f,0And W_f,1Each of which contains M basis vectors,

and

each of which contains 2L x M coefficients.

Wherein the CSI first part comprises:

RI；

a wideband CQI;

a differential CQI;

and the indication information of the total number of the nonzero coefficients is used for indicating the sum of the numbers of the nonzero differential amplitude coefficients of the layer one and the layer two.

The CSI second part includes:

a beam index indicating orthogonal beams used to construct a precoding matrix;

position indication information of the non-zero coefficients of layer one, indicating the coefficient matrix corresponding to the non-zero differential amplitude coefficients of layer one in the layer one for constructing the precoding matrix (i.e. in equation 7)

) The position of (1);

the index of the strongest amplitude coefficient of layer one indicates the coefficient matrix corresponding to the strongest amplitude coefficient of layer one in layer one for constructing the precoding matrix (i.e., in equation 7)

) The position of (1);

a reference amplitude coefficient for layer one;

a differential amplitude coefficient of layer one;

the phase amplitude coefficient of layer one;

a base vector index of layer two indicating a base vector corresponding to layer two for constructing a precoding matrix;

position indication information of the non-zero coefficient of the layer two, indicating the coefficient matrix corresponding to the non-zero differential amplitude coefficient of the layer two for constructing the precoding matrix (i.e. in equation 8)

) The position of (1);

the index of the strongest amplitude coefficient of layer two indicates the coefficient matrix corresponding to the strongest amplitude coefficient of layer two in layer two for constructing the precoding matrix (i.e. in equation 8)

) The position of (1);

a reference amplitude coefficient for layer two;

the differential amplitude coefficient of layer two;

phase amplitude coefficient of layer two.

Optionally, in example 2, the number of bits occupied by the strongest amplitude coefficient index of each layer in the second portion of CSI is related to the number of non-zero coefficients of each layer. Since the first part of the CSI does not include the number indication information of the nonzero coefficients of each layer, the terminal uses the maximum number K of the nonzero coefficients allowed by each layer configured by the base station when feeding back the indication information of the total number of the nonzero coefficients₀To determine the number of bits occupied by the strongest amplitude coefficient index for each layer. Wherein, the bit number occupied by the strongest amplitude coefficient index of layer one is log₂(K₀) The bit number occupied by the strongest amplitude coefficient index of layer two is log₂(K₀)。

Example 3

For each layer, the base station configures a precoding matrix using 2L beams, and forms a compressed base vector set using M base vectors. For each layer, the terminal reports K at most₀A non-zero coefficient (where K₀<2L × M). For the Type II codebook with rank2, its first layer precoding is represented by the following equation (9):

the second layer precoding is expressed as the following equation (10):

and

each containing 2L M coefficients.

The CSI first part includes:

RI；

a wideband CQI;

a differential CQI;

The CSI second part includes:

a beam index indicating orthogonal beams used to construct a precoding matrix;

position indication information of non-zero coefficients of layer one and layer two, indicating coefficient matrix corresponding to non-zero differential amplitude coefficient of layer one in layer one for constructing precoding matrix (i.e. in equation 9)

) And the non-zero difference amplitude coefficient of layer two is in the coefficient matrix corresponding to layer two used to construct the precoding matrix (i.e., in equation 10)

) The position of (1); the indication information is joint indication information, namely different values of the indication information correspond to different combinations of the non-zero coefficient position of the layer one and the non-zero coefficient position of the layer two;

the indexes of the strongest amplitude coefficients of layer one and layer two indicate the coefficient matrix corresponding to the strongest amplitude coefficient of layer one in layer one for constructing the precoding matrix (i.e., in equation 9)

) And the coefficient matrix corresponding to the strongest amplitude coefficient of layer one in the layer one used to construct the precoding matrix (i.e., in equation 10)

) The position of (1); the indication information is joint indication information, namely different values of the indication information correspond to different combinations of indexes of the strongest amplitude coefficient of the layer one and the strongest amplitude coefficient of the layer two;

a reference amplitude coefficient for layer one;

a differential amplitude coefficient of layer one;

the phase amplitude coefficient of layer one;

a reference amplitude coefficient for layer two;

the differential amplitude coefficient of layer two;

phase amplitude coefficient of layer two.

Optionally, in example 3, the second part of the CSI indicates an index of a strongest amplitude coefficient of each layer in a joint reporting manner, where the number of bits occupied by the index is

Wherein

The number of combinations represents the selection of j numbers (j) from the i numbers<I). Or the index of the strongest amplitude coefficient of each layer is indicated by adopting a joint reporting mode, and the bit number occupied by the index is

Wherein K_NZRepresents the sum of the number of non-zero differential amplitude coefficients for layer one and layer two,

the number of combinations represents the selection of j numbers (j) from the i numbers<I). In this way, the index of the strongest amplitude coefficient for each layer can be indicated at the same time. Further, when the total number of the nonzero coefficients is small, the position of the nonzero coefficient of each layer can be indicated in a joint reporting mode. Optionally, the position indication information of the non-zero coefficients of layer one and layer two is adopted

A bit indication. Wherein K_NZRepresenting the sum of the number of non-zero coefficients.

Example 4

For each layer, the base station configures a precoding matrix using 2L beams, and forms a compressed base vector set using M base vectors. For each layer, the terminal reports K at most₀A non-zero coefficient (where K0<2L × M). For the Type II codebook with rank ═ 3, the codebook structure thereof can refer to any one of the above examples 2 or 3, and the description thereof is omitted.

The CSI first part includes:

RI；

a wideband CQI;

a differential CQI;

and the indication information of the total number of the nonzero coefficients is used for indicating the sum of the number of the nonzero differential amplitude coefficients of the layer I, the layer II and the layer III.

The CSI second part includes:

a beam index indicating orthogonal beams used to construct a precoding matrix;

the position indication information of the non-zero coefficient of the layer I indicates the position of the non-zero differential amplitude coefficient of the layer I in a coefficient matrix corresponding to the layer I for constructing a precoding matrix;

the index of the strongest amplitude coefficient of the layer one indicates the position of the strongest amplitude coefficient of the layer one in a coefficient matrix corresponding to the layer one for constructing a precoding matrix;

a reference amplitude coefficient for layer one;

a differential amplitude coefficient of layer one;

the phase amplitude coefficient of layer one;

position indication information of the non-zero coefficient of the layer two indicates the position of the non-zero differential amplitude coefficient of the layer two in a coefficient matrix corresponding to the layer two for constructing a precoding matrix;

the index of the strongest amplitude coefficient of the layer two indicates the position of the strongest amplitude coefficient of the layer two in a coefficient matrix corresponding to the layer two for constructing a precoding matrix;

a reference amplitude coefficient for layer two;

the differential amplitude coefficient of layer two;

the phase amplitude coefficient of layer two;

a base vector index of layer three indicating a base vector corresponding to layer three for constructing a precoding matrix;

position indication information of the non-zero coefficient of the layer three indicates the position of the non-zero differential amplitude coefficient of the layer three in a coefficient matrix corresponding to the layer three for constructing a precoding matrix;

the index of the strongest amplitude coefficient of the layer three indicates the position of the strongest amplitude coefficient of the layer three in a coefficient matrix corresponding to the layer three for constructing a precoding matrix;

a reference amplitude coefficient for layer three;

the differential amplitude coefficient of layer three;

phase amplitude coefficient of layer three.

Optionally, the number of bits occupied by the strongest amplitude coefficient index of each layer is log₂(K_NZ) In which K is_NZRepresenting the sum of the number of non-zero coefficients of all layers, i.e. the index of the strongest amplitude coefficient of each layer is K_NZOne of the indices.

Based on the same technical concept, the embodiment of the invention also provides a terminal and a network device, which can be respectively applied to the embodiment.

Fig. 3 is a schematic structural diagram of a terminal according to an embodiment of the present invention. As shown, the terminal may include: a processing module 301 and a sending module 302, wherein:

a processing module 301, configured to perform channel measurement to obtain a coefficient set for feedback, where the coefficient set includes an amplitude coefficient set and a phase coefficient set of at least one layer, the amplitude coefficient set includes a differential amplitude coefficient and a reference amplitude coefficient, and the coefficient set is used to construct a precoding matrix;

a sending module 302, configured to send CSI to a network device, where the CSI includes the coefficient set and indication information of a strongest amplitude coefficient, and the indication information of the strongest amplitude coefficient is used to indicate a strongest amplitude coefficient of at least one layer.

The functions of the modules in the terminal can be referred to the description of the functions implemented by the terminal in the foregoing embodiments, and are not repeated here.

Fig. 4 is a schematic structural diagram of a network device according to an embodiment of the present invention. As shown, the network device may include: a receiving module 401 and a processing module 402, wherein:

a receiving module 401, configured to receive CSI sent by a terminal, where the CSI includes a coefficient set used for constructing a precoding matrix and indication information including a strongest amplitude coefficient, where the coefficient set includes an amplitude coefficient set of at least one layer and a phase coefficient set, the amplitude coefficient set includes a differential amplitude coefficient and a reference amplitude coefficient, the coefficient set is used for constructing a precoding matrix, and the indication information of the strongest amplitude coefficient is used for indicating the strongest amplitude coefficient of the at least one layer;

a processing module 402, configured to construct a precoding matrix corresponding to the terminal according to the CSI.

The functions of the modules in the network device may refer to the descriptions of the functions implemented by the network device in the foregoing embodiments, and are not repeated here.

Based on the same technical concept, the embodiment of the present application further provides a communication device, which can implement the functions of the terminal side in the foregoing embodiments.

Referring to fig. 5, a schematic structural diagram of a communication device according to an embodiment of the present application is provided. As shown, the communication device may include: a processor 501, a memory 502, a transceiver 503, and a bus interface 504.

The processor 501 is responsible for managing the bus architecture and general processing, and the memory 502 may store data used by the processor 501 in performing operations. The transceiver 503 is used to receive and transmit data under the control of the processor 501.

The bus architecture may include any number of interconnected buses and bridges, with one or more processors, represented by processor 501, and various circuits, represented by memory 502, being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The processor 501 is responsible for managing the bus architecture and general processing, and the memory 502 may store data used by the processor 501 in performing operations.

The process disclosed in the embodiment of the present invention may be applied to the processor 501, or implemented by the processor 501. In implementation, the steps of the signal processing flow may be implemented by integrated logic circuits of hardware or instructions in the form of software in the processor 501. The processor 501 may be a general purpose processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof that may implement or perform the methods, steps, and logic blocks disclosed in embodiments of the present invention. A general purpose processor may be a microprocessor or any conventional processor or the like. The steps of a method disclosed in connection with the embodiments of the present invention may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in the processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in the memory 502, and the processor 501 reads the information in the memory 502 and completes the steps of the signal processing flow in combination with the hardware thereof.

Specifically, the processor 501 is configured to read the computer instructions in the memory 502 and execute the functions implemented on the terminal side in the flow shown in fig. 1.

Based on the same technical concept, the embodiment of the present application further provides a communication apparatus, which can implement the functions of the network device side in the foregoing embodiments.

Referring to fig. 6, a schematic structural diagram of a communication device according to an embodiment of the present application is provided. As shown, the communication device may include: a processor 601, a memory 602, a transceiver 603, and a bus interface 604.

The processor 601 is responsible for managing the bus architecture and general processing, and the memory 602 may store data used by the processor 601 in performing operations. The transceiver 603 is used for receiving and transmitting data under the control of the processor 601.

The bus architecture may include any number of interconnected buses and bridges, with one or more processors, represented by processor 601, and various circuits of memory, represented by memory 602, being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The processor 601 is responsible for managing the bus architecture and general processing, and the memory 602 may store data used by the processor 601 in performing operations.

The process disclosed by the embodiment of the invention can be applied to the processor 601 or implemented by the processor 601. In implementation, the steps of the signal processing flow may be implemented by integrated logic circuits of hardware or instructions in the form of software in the processor 601. The processor 601 may be a general purpose processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or the like that implement or perform the methods, steps, and logic blocks disclosed in embodiments of the present invention. A general purpose processor may be a microprocessor or any conventional processor or the like. The steps of a method disclosed in connection with the embodiments of the present invention may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in the processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in the memory 602, and the processor 601 reads the information in the memory 602 and completes the steps of the signal processing flow in combination with the hardware thereof.

Specifically, the processor 601 is configured to read the computer instructions in the memory 602 and execute the functions implemented on the network device side in the flow shown in fig. 2.

The embodiment of the present application further provides a computer-readable storage medium, where the computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable the computer to execute the method executed by the terminal in the foregoing embodiment.

An embodiment of the present application further provides a computer-readable storage medium, where the computer-readable storage medium stores computer-executable instructions, where the computer-executable instructions are configured to enable the computer to execute the method performed by the network device in the foregoing embodiment.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A method for feeding back channel state information, the method comprising:

the terminal carries out channel measurement to obtain a coefficient set for feedback, wherein the coefficient set comprises at least one layer of amplitude coefficient set and phase coefficient set, the amplitude coefficient set comprises a differential amplitude coefficient and a reference amplitude coefficient, and the coefficient set is used for constructing a precoding matrix;

and the terminal sends Channel State Information (CSI) to network equipment, wherein the CSI comprises the coefficient set and the indication information of the strongest amplitude coefficient, and the indication information of the strongest amplitude coefficient is used for indicating the strongest amplitude coefficient of at least one layer.

2. The method of claim 1, wherein the information indicative of the strongest amplitude coefficient comprises an index of the strongest amplitude coefficient of at least one layer;

the number of bits occupied by the index of the strongest amplitude coefficient of the at least one layer is determined by the maximum value of the number of nonzero coefficients of each layer which allows feedback, or is determined by the maximum value of the number of nonzero coefficients of all layers which allow feedback and/or the number of feedback layers, or is determined by the total number of nonzero coefficients of all layers which allow feedback and/or the number of feedback layers, wherein the maximum value of the number of nonzero coefficients which allow feedback is predefined by a system or configured to the terminal by network equipment.

3. The method of claim 1, wherein the indication information of the strongest amplitude coefficient of each of the at least one layer comprises first indication information corresponding to the respective layer, the first indication information indicating an index of the strongest amplitude coefficient of the respective layer; or

The indication information of the strongest amplitude coefficient comprises second indication information, the second indication information is used for indicating the index of the strongest amplitude coefficient of the at least one layer, and different values of the second indication information indicate different combinations of the indexes of the strongest amplitude coefficients of the at least one layer.

4. The method of claim 1, wherein the CSI further comprises information indicating the number of non-zero coefficients of at least one layer and information indicating the location of non-zero coefficients of at least one layer; wherein the non-zero coefficients include non-zero differential amplitude coefficients, and the position indication information of the non-zero coefficients of the at least one layer is used to indicate the positions of the non-zero coefficients of the at least one layer in the coefficient sets of the respective layers used to construct the precoding matrix.

5. The method of claim 4, wherein the position indication information of the non-zero coefficient of the at least one layer is represented by a bit sequence comprising at least N bits, and a value of the N is determined according to a value of the reference amplitude coefficient of the at least one layer.

6. The method of claim 5, wherein if the reference amplitude coefficient is not zero, then N-2L M; if the values of the reference amplitude coefficients are all zero, N is L M;

where L denotes the number of orthogonal beams in the orthogonal beam group used to construct the precoding matrix, and M denotes the number of basis vectors used to construct the precoding matrix.

7. The method of claim 5, wherein the CSI further includes weak polarization indication information of at least one layer, and the weak polarization indication information is used to indicate whether all differential amplitude coefficient values of one polarization direction of the at least one layer are all zero;

if the weak polarization indication information indicates that all differential amplitude coefficient values in one polarization direction of the at least one layer are all zero, the CSI does not include the reference amplitude coefficient or the reference amplitude coefficient set of the at least one layer.

8. The method of claim 7, wherein the CSI further comprises polarization direction indication information for indicating the polarization directions in which all differential amplitude coefficients of the two polarization directions have zero values.

9. The method according to claim 7, wherein if the weak polarization indication information indicates that all differential amplitude coefficient values of one polarization direction of the at least one layer include a non-zero value, then N-2L × M; if the weak polarization indication information indicates that all the differential amplitude coefficient values in one polarization direction of the at least one layer are all zero, then N is L M;

10. The method of claim 4, wherein position indication information of the non-zero coefficients of each of at least one layer is indicated using first indication information indicating positions of the non-zero coefficients of the corresponding layer in a coefficient set of the layer used for constructing the precoding matrix; or

And indicating the position indication information of the nonzero coefficient of at least one layer by using second indication information, wherein different values of the second indication information indicate different combinations of the positions of the nonzero coefficients of at least one layer.

11. The method of any one of claims 1-10, wherein the CSI comprises a first portion and a second portion;

the first part of the CSI comprises: a reference amplitude coefficient set of each layer, and quantity indication information of non-zero coefficients of each layer;

the second part of the CSI comprises: the precoding matrix comprises a differential amplitude coefficient set and a phase coefficient set of each layer, indication information of the strongest amplitude coefficient of each layer, and position indication information of a non-zero coefficient of each layer, wherein the position indication information of the non-zero coefficient of each layer is used for indicating the position of the non-zero coefficient of each layer in the coefficient set of the corresponding layer for constructing the precoding matrix.

12. The method of any one of claims 1-10, wherein the CSI comprises a first portion and a second portion;

the first part of the CSI comprises: information indicative of a total number of non-zero coefficients for all layers; the bit number occupied by the indication information of the total number of the nonzero coefficients of all the layers is determined according to the maximum value of the number of the nonzero coefficients allowed to be fed back by each layer, or is determined according to the maximum value of the total number of the nonzero coefficients allowed to be fed back by all the layers;

the second part of the CSI comprises: the precoding matrix comprises a reference amplitude coefficient set, a differential amplitude coefficient set and a phase coefficient set of each layer, indication information of a strongest amplitude coefficient of each layer or combination indication information of the strongest amplitude coefficients of all layers, and position indication information of a non-zero coefficient of each layer, wherein the position indication information of the non-zero coefficient of each layer is used for indicating the position of the non-zero coefficient of each layer in the coefficient set of the corresponding layer used for constructing the precoding matrix.

13. The method of claim 11 or 12, wherein the first portion of CSI further comprises at least one of rank indication, RI, wideband channel quality indication, CQI, differential COI;

the second portion of the CSI further comprises: at least one of a beam index, a basis vector index.

14. A method for feeding back channel state information, comprising:

the method comprises the steps that network equipment receives Channel State Information (CSI) sent by a terminal, wherein the CSI comprises a coefficient set which is measured by the terminal and used for constructing a precoding matrix and indication information of a strongest amplitude coefficient, the coefficient set comprises an amplitude coefficient set and a phase coefficient set of at least one layer, the amplitude coefficient set comprises a differential amplitude coefficient and a reference amplitude coefficient, and the indication information of the strongest amplitude coefficient is used for indicating the strongest amplitude coefficient of at least one layer;

and the network equipment constructs a precoding matrix corresponding to the terminal according to the CSI.

15. The method of claim 14, wherein the information indicative of the strongest amplitude coefficient comprises an index of the strongest amplitude coefficient of at least one layer;

16. The method of claim 14, wherein the indication information of the strongest amplitude coefficient of the at least one layer comprises first indication information corresponding to the respective layer, the first indication information indicating an index of the strongest amplitude coefficient of the respective layer; or

17. The method of claim 14, wherein the CSI further comprises information indicating the number of non-zero coefficients of at least one layer and information indicating the location of non-zero coefficients of at least one layer; wherein the non-zero coefficients include non-zero differential amplitude coefficients, and the position indication information of the non-zero coefficients of the at least one layer is used to indicate the positions of the non-zero coefficients of the at least one layer in the coefficient sets of the respective layers used to construct the precoding matrix.

18. The method of claim 17, wherein the position indication information of the non-zero coefficient of the at least one layer is represented by a bit sequence comprising at least N bits, and wherein a value of N is determined according to a value of a reference amplitude coefficient of the at least one layer.

19. The method of claim 18, wherein if the reference amplitude coefficient does not take on a value of zero, then N-2L x M; if the values of the reference amplitude coefficients are all zero, N is L M;

20. The method of claim 18, wherein the CSI further includes weak polarization indication information of at least one layer, where the weak polarization indication information is used to indicate whether all differential amplitude coefficient values of one polarization direction of the at least one layer are all zero;

21. The method of claim 20, wherein the CSI further comprises polarization direction indication information for indicating the polarization directions in which all differential amplitude coefficients of the two polarization directions have zero values.

22. The method according to claim 20, wherein if the weak polarization indication information indicates that all differential amplitude coefficient values of one polarization direction of the at least one layer include a non-zero value, then N-2L × M; if the weak polarization indication information indicates that all the differential amplitude coefficient values in one polarization direction of the at least one layer are all zero, then N is L M;

23. The method of claim 17, wherein position indication information of the non-zero coefficients of each of at least one layer is indicated using first indication information indicating positions of the non-zero coefficients of the corresponding layer in a coefficient set of the layer used for constructing the precoding matrix; or

24. The method of any one of claims 14-23, wherein the CSI comprises a first portion and a second portion;

25. The method of any one of claims 14-23, wherein the CSI comprises a first portion and a second portion;

26. The method of claim 24 or 25, wherein the first portion of CSI further comprises at least one of rank indication, RI, wideband channel quality indication, CQI, differential COI;

27. A terminal, comprising:

the system comprises a processing module, a precoding matrix generation module and a feedback module, wherein the processing module is used for carrying out channel measurement to obtain a coefficient set for feedback, the coefficient set comprises at least one layer of amplitude coefficient set and a phase coefficient set, the amplitude coefficient set comprises a differential amplitude coefficient and a reference amplitude coefficient, and the coefficient set is used for constructing the precoding matrix;

and the sending module is used for sending Channel State Information (CSI) to network equipment, wherein the CSI comprises the coefficient set and the indication information of the strongest amplitude coefficient, and the indication information of the strongest amplitude coefficient is used for indicating the strongest amplitude coefficient of at least one layer.

28. A network device, comprising:

a receiving module, configured to receive channel state information CSI sent by a terminal, where the CSI includes a coefficient set used for constructing a precoding matrix and indication information including a strongest amplitude coefficient, where the coefficient set includes an amplitude coefficient set of at least one layer and a phase coefficient set, the amplitude coefficient set includes a differential amplitude coefficient and a reference amplitude coefficient, and the indication information of the strongest amplitude coefficient is used to indicate the strongest amplitude coefficient of the at least one layer;

and the processing module is used for constructing a precoding matrix corresponding to the terminal according to the CSI.

29. A communications apparatus, comprising: a processor, memory, transceiver; the processor, reading the computer instructions in the memory, performing the method of any of claims 1-13.

30. A communications apparatus, comprising: a processor, memory, transceiver; the processor, configured to read the computer instructions in the memory, to perform the method according to any one of claims 14-26.

31. A computer-readable storage medium having stored thereon computer-executable instructions for causing a computer to perform the method of any one of claims 1-13.

32. A computer-readable storage medium having stored thereon computer-executable instructions for causing a computer to perform the method of any one of claims 14-26.