CN111726155B

CN111726155B - CSI feedback method, receiving method, terminal and network side equipment

Info

Publication number: CN111726155B
Application number: CN201910217253.7A
Authority: CN
Inventors: 刘正宣; 高秋彬; 李辉; 陈润华
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2019-03-21
Filing date: 2019-03-21
Publication date: 2022-06-10
Anticipated expiration: 2039-03-21
Also published as: CN111726155A

Abstract

The embodiment of the invention provides a CSI feedback method, a receiving method, a terminal and network side equipment, wherein the method comprises the following steps: the terminal preprocesses the phase corresponding to the sub-band coefficient to obtain the preprocessed sub-band coefficient; the terminal compresses the preprocessed sub-band coefficient to obtain a compressed coefficient; and the terminal feeds back the CSI corresponding to the compression coefficient to network side equipment. The embodiment of the invention can improve the accuracy of CSI feedback.

Description

CSI feedback method, receiving method, terminal and network side equipment

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a Channel State Information (CSI) feedback method, a receiving method, a terminal, and a network side device.

Background

A Type II (Type II) CSI codebook is defined in a New Radio (NR) system, the Type II CSI codebook has higher channel quantization precision but high feedback overhead, and therefore, a low-overhead Type II CSI codebook is provided, and the Type II CSI codebook is obtained based on linear combination of orthogonal beams and subband coefficient compression. For example: the compressed Type II CSI codebook can be used

Denotes W₁Representing a matrix of beam vectors (otherwise known as an orthogonal combined beam matrix), W₂Represents a subband coefficient matrix comprising the respective subband coefficients, Q and D represent an amplitude coefficient matrix and a phase coefficient matrix, respectively, the symbol x represents a dot product of the two matrices,

denotes the compression factor, W_fRepresenting the compressed basis vectors. But is currently directly on W₂Is compressed to obtain

Thus making the accuracy of CSI feedback low.

Disclosure of Invention

The embodiment of the invention provides a CSI feedback method, a CSI receiving method, a terminal and network side equipment, and aims to solve the problem of low accuracy of CSI feedback.

The embodiment of the invention provides a CSI feedback method, which comprises the following steps:

the terminal preprocesses the phase corresponding to the sub-band coefficient to obtain the preprocessed sub-band coefficient;

the terminal compresses the preprocessed sub-band coefficient to obtain a compressed coefficient;

and the terminal feeds back the CSI corresponding to the compression coefficient to network side equipment.

Optionally, the subband coefficient includes a phase coefficient matrix, and the preprocessing the phase corresponding to the subband coefficient by the terminal to obtain a preprocessed subband coefficient includes:

and the terminal respectively executes first operation on at least one column of the phase coefficient matrix to obtain preprocessed subband coefficients, wherein the first operation of the nth column is to perform first operation on at least one phase coefficient of the nth column and a phase value corresponding to the nth column, N belongs to { 0.,. N-1}, and N represents the number of subbands.

Optionally, the terminal respectively performs a first operation on at least one column of the phase coefficient matrix, where the first operation includes:

and the terminal respectively executes first operation on all columns of the phase coefficient matrix, wherein the first operation of the nth column is to respectively subtract at least one phase coefficient of the nth column by a phase value corresponding to the nth column.

Optionally, the phase value corresponding to the nth column is:

the phase value of the nth column in the phase coefficient matrix or the ith row in the target column, wherein l is an integer greater than or equal to 0; or alternatively

And subtracting the phase value of the l row in the n column of the target phase coefficient matrix from the phase value of the l row in the n column of the phase coefficient matrix to obtain a phase value, wherein the target phase coefficient matrix is obtained by calculation according to the channel information of the receiving antenna on the subband n.

Optionally, the l-th action:

a row is randomly selected from the phase coefficient matrix; or

And the wideband coefficient vector is obtained by calculation according to a bandwidth channel and a beam vector matrix corresponding to the CSI.

Optionally, the step of preprocessing, by the terminal, the phase corresponding to the subband coefficient to obtain a preprocessed subband coefficient includes:

The terminal respectively carries out second operation on at least one element in the characteristic vector of the subband N and the phase value corresponding to the subband N to obtain a target characteristic vector of the subband N, wherein N belongs to { 0.,. N-1}, and N represents the number of the subbands;

and the terminal calculates the subband coefficient of the subband n according to the target characteristic vector of the subband n and the beam vector matrix corresponding to the CSI.

Optionally, the second operation is performed by the terminal on at least one element in the feature vector of the subband n and the phase value corresponding to the subband n, and includes:

and the terminal respectively adds at least one element in the characteristic vector of the subband n to the phase value corresponding to the subband n.

Optionally, the phase value corresponding to the subband n is:

in which e_nFeature vector representing subband n, e₀Representing the feature vector for subband 0.

Optionally, when the Rank corresponding to the CSI is greater than 1, the terminal respectively performs a first operation on at least one column of the phase coefficient matrix, where the first operation includes:

and the terminal respectively executes first operation on at least one column of the phase coefficient matrix of at least one layer.

Optionally, when Rank corresponding to the CSI is greater than 1, performing, by the terminal, a second operation on at least one element in the feature vector of the subband n and the phase value corresponding to the subband n to obtain a target feature vector of the subband n, where the second operation includes:

And the terminal performs second operation on at least one element of the subband n in the characteristic vector of at least one layer and the phase value corresponding to the subband n to obtain a target characteristic vector of the subband n.

An embodiment of the present invention further provides a CSI receiving method, including:

and the network side equipment receives CSI fed back by the terminal, wherein the compression coefficient corresponding to the CSI is a compression coefficient obtained by preprocessing the phase corresponding to the subband coefficient by the terminal and compressing the preprocessed subband coefficient.

An embodiment of the present invention further provides a terminal, including:

the processing module is used for preprocessing the phase corresponding to the subband coefficient to obtain a preprocessed subband coefficient;

the compression module is used for compressing the preprocessed sub-band coefficient to obtain a compression coefficient;

and the feedback module is used for feeding back the CSI corresponding to the compression coefficient to network side equipment.

Optionally, the subband coefficients include a phase coefficient matrix, and the processing module is configured to perform a first operation on at least one column of the phase coefficient matrix to obtain preprocessed subband coefficients, where the first operation on an nth column is to perform a first operation on at least one phase coefficient of the nth column and a phase value corresponding to the nth column, N is ∈ { 0., N-1}, and N represents a subband number.

Optionally, the processing module is configured to perform a first operation on all columns of the phase coefficient matrix, where the first operation on the nth column is to subtract at least one phase coefficient of the nth column from a phase value corresponding to the nth column.

Optionally, the processing module includes:

the first calculation unit is used for performing second operation on at least one element in the feature vector of the subband N and the phase value corresponding to the subband N to obtain a target feature vector of the subband N, wherein N belongs to { 0.,. N-1}, and N represents the number of the subbands;

and the second calculating unit is used for calculating the subband coefficient of the subband n according to the target characteristic vector of the subband n and the beam vector matrix corresponding to the CSI.

Optionally, the processing module is configured to add a phase value corresponding to the subband n to at least one element in the feature vector of the subband n.

An embodiment of the present invention further provides a network side device, including:

and the receiving module is used for receiving the CSI fed back by the terminal, wherein the compression coefficient corresponding to the CSI is a compression coefficient obtained by preprocessing the phase corresponding to the subband coefficient by the terminal and compressing the preprocessed subband coefficient.

An embodiment of the present invention further provides a terminal, including: a transceiver, a memory, a processor, and a program stored on the memory and executable on the processor,

the transceiver is used for preprocessing the phase corresponding to the sub-band coefficient to obtain a preprocessed sub-band coefficient; compressing the preprocessed sub-band coefficient to obtain a compressed coefficient; feeding back CSI corresponding to the compression coefficient to network side equipment;

alternatively, the first and second electrodes may be,

the processor is used for preprocessing the phase corresponding to the subband coefficient to obtain a preprocessed subband system; compressing the preprocessed sub-band coefficient to obtain a compressed coefficient;

and the transceiver is used for feeding back the CSI corresponding to the compression coefficient to network side equipment.

Optionally, the subband coefficient includes a phase coefficient matrix, and the preprocessing is performed on a phase corresponding to the subband coefficient to obtain a preprocessed subband coefficient, including:

and respectively executing first operation on at least one column of the phase coefficient matrix to obtain preprocessed subband coefficients, wherein the first operation on the nth column is to perform first operation on at least one phase coefficient of the nth column and a phase value corresponding to the nth column, N belongs to { 0.,. N-1}, and N represents the number of subbands.

and respectively executing a first operation on all columns of the phase coefficient matrix, wherein the first operation on the nth column is to respectively subtract at least one phase coefficient of the nth column by a phase value corresponding to the nth column.

Optionally, the preprocessing the phase corresponding to the subband coefficient to obtain a preprocessed subband coefficient includes:

performing second operation on at least one element in the feature vector of the subband N and the phase value corresponding to the subband N to obtain a target feature vector of the subband N, wherein N belongs to { 0.,. N-1}, and N represents the number of the subbands;

and calculating the subband coefficient of the subband n according to the target characteristic vector of the subband n and the beam vector matrix corresponding to the CSI.

Optionally, the performing a second operation on at least one element in the feature vector of the subband n and the phase value corresponding to the subband n includes:

and respectively adding at least one element in the characteristic vector of the subband n to the phase value corresponding to the subband n.

An embodiment of the present invention further provides a network side device, including: a transceiver, a memory, a processor, and a program stored on the memory and executable on the processor,

The transceiver is configured to receive CSI fed back by a terminal, where the compression coefficient corresponding to the CSI is a compression coefficient obtained by preprocessing a phase of a subband coefficient or a feature vector of a subband by the terminal and compressing the preprocessed subband coefficient.

Embodiments of the present invention further provide a computer-readable storage medium, on which a computer program is stored, where the computer program, when executed by a processor, implements steps in a CSI feedback method provided in an embodiment of the present invention, or the computer program, when executed by the processor, implements steps in a CSI receiving method provided in an embodiment of the present invention.

In the embodiment of the invention, a terminal preprocesses the phase corresponding to the sub-band coefficient to obtain the preprocessed sub-band coefficient; the terminal compresses the preprocessed sub-band coefficient to obtain a compressed coefficient; and the terminal feeds back the CSI corresponding to the compression coefficient to network side equipment. Because the phase is preprocessed before compression, the correlation of the subband coefficient can be increased, the compression loss information is less, and the accuracy of CSI feedback is improved.

Drawings

FIG. 1 is a schematic diagram of a network architecture to which embodiments of the present invention are applicable;

Fig. 2 is a flowchart of a CSI feedback method according to an embodiment of the present invention;

fig. 3 is a flowchart of a CSI receiving method according to an embodiment of the present invention;

fig. 4 is a structural diagram of a terminal according to an embodiment of the present invention;

fig. 5 is a block diagram of another terminal provided in an embodiment of the present invention;

fig. 6 is a structural diagram of a network side device according to an embodiment of the present invention;

fig. 7 is a block diagram of another terminal according to an embodiment of the present invention;

fig. 8 is a structural diagram of another network-side device according to an embodiment of the present invention.

Detailed Description

To make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.

Referring to fig. 1, fig. 1 is a schematic diagram of a network structure to which the embodiment of the present invention is applicable, and as shown in fig. 1, the network structure includes a terminal 11 and a network side device 12, where the terminal 11 may be a User Equipment (UE) or other terminal devices, for example: terminal side equipment such as a Mobile phone, a Tablet Personal Computer (Tablet Personal Computer), a Laptop Computer (Laptop Computer), a Personal Digital Assistant (PDA), a Mobile Internet Device (MID), or a Wearable Device (Wearable Device) is not limited to a specific type of terminal in the embodiments of the present invention. The network side device 12 may be a base station, for example: macro station, LTE eNB, 5G NR NB, etc.; the network side device may also be a small station, such as a Low Power Node (LPN), pico, femto, or an Access Point (AP); the network side device may also be a network node formed by a Central Unit (CU) and a plurality of Transmission Reception Points (TRPs) managed and controlled by the CU. It should be noted that, in the embodiment of the present invention, the specific type of the network-side device is not limited.

Referring to fig. 2, fig. 2 is a flowchart of a CSI feedback method according to an embodiment of the present invention, and as shown in fig. 2, the method includes the following steps:

step 201, the terminal preprocesses the phase corresponding to the sub-band coefficient to obtain the preprocessed sub-band coefficient;

step 202, the terminal compresses the preprocessed sub-band coefficient to obtain a compressed coefficient;

and 203, the terminal feeds back the CSI corresponding to the compression coefficient to network side equipment.

The phase preprocessing corresponding to the subband coefficient may be preprocessing corresponding phases of all or part of subband coefficients of the CSI codebook, for example: for subband coefficient matrix W₂The phase of the subband coefficients in (1) is preprocessed, e.g. the subband coefficient matrix W₂And preprocessing the phase coefficient in the corresponding phase coefficient matrix D.

In addition, the preprocessing may be to perform an operation for increasing the correlation of the subband coefficients on the phases corresponding to the subband coefficients, for example: each column element in the phase coefficient matrix is added or subtracted with the phase value corresponding to the column to increase the correlation of the adjacent subband coefficients.

It should be noted that the phase corresponding to the subband coefficient may be the phase of the subband coefficient, for example: the phase coefficient in the phase coefficient matrix, or the phase corresponding to the subband coefficient may be a phase of an object associated with the subband coefficient, such as a eigenvector of the subband or a channel of the subband.

The compressing the subband coefficients may be frequency domain or time domain compressing the preprocessed subband coefficients to obtain compressed coefficients

For example: by using

The above-mentioned compression is carried out, wherein,

represents the above compression factor, W_fDenotes a compressed base vector, W'₂Representing the preprocessed subband coefficient matrix.

The feedback of the CSI corresponding to the compression coefficient to the network side device may be feedback of CSI including quantization information (or referred to as compression coefficient information) of the compression coefficient. Terminal utilization of compressed basis vector W_fAnd the preprocessing is carried out to obtain a sub-band coefficient matrix W'₂According to

Calculating the compression factor

Then to

And feeding back the quantized data to the network side equipment. It should be noted that, in the embodiments of the present invention, how to determine the compression coefficient is reversedThe feedback method of feeding the corresponding CSI is not limited. Preferably, the feedback CSI may include compressed coefficient information corresponding to the compressed coefficient reported by the terminal, compressed base vector indication information, and orthogonal beam indication information.

According to the embodiment of the invention, the phase can be preprocessed before compression through the steps, so that the correlation of the subband coefficient can be increased, the compression loss information is less, and the accuracy of CSI feedback is improved.

For example: the parameters required by the Type II CSI codebook may include a beam vector matrix (alternatively referred to as an orthogonal combined beam matrix) W₁Compression factor

And compressing the basis vector W_fWherein, in the process,

is based on a subband coefficient matrix W₂And a compressed base vector W_fThus, the sub-band coefficient matrix W can be obtained through the steps₂Before compression, the phase of the subband coefficient needs to be preprocessed to increase the correlation of the subband coefficient, so that the compression loss information is less, and the accuracy of CSI feedback is improved.

As an optional implementation manner, the subband coefficient includes a phase coefficient matrix, and the preprocessing, by the terminal, a phase corresponding to the subband coefficient to obtain a preprocessed subband coefficient includes:

Wherein, the phase value corresponding to the nth column can be used as the phase value

To representAnd the phase values corresponding to different columns may be the same or different. The at least one phase coefficient of the nth column may be all or part of the phase coefficients of the nth column. The first operation performed on the at least one phase coefficient of the nth column and the phase value corresponding to the nth column may be performed on the at least one phase coefficient of the same column and the same phase value.

Due to W₂Q, exp (D), so that the phase coefficient matrix may be represented by D, and the phase coefficient of each subband may be included in the matrix, and as an example, Rank 1, D may be represented as follows:

wherein, L is the number of orthogonal beams, and N is the number of sub-bands.

In this embodiment, when performing the first operation, the first operation is performed on each column with the corresponding phase value, so that the correlation between adjacent subband coefficients is increased and the compression loss information is reduced.

Preferably, the first operation of the nth column may be performed by subtracting phase values from at least one phase coefficient of the nth column

Of course, this is not limited, for example: the first operation of the nth column may be adding all or part of the phase coefficient of the nth column to a phase value

In addition, since the value of N may be any integer from 0 to N-1, in this manner, the first operation may be performed on the phase coefficients of all columns in the phase coefficient matrix. For example: in a preferred embodiment, the terminal performs a first operation on at least one column of the phase coefficient matrix, respectively, and includes:

This allows all columns of the phase coefficient matrix to perform the first operation separately so that the correlation of adjacent subband coefficients is enhanced.

Of course, in the embodiment of the present invention, it is not limited to perform the first operation on all columns of the phase coefficient matrix, for example: in some scenarios, the first operation may be performed only on a part of the columns, so that the correlation of partial subband coefficients may be increased, and the compression loss information may be reduced.

In the above embodiment, the terminal may calculate the subband coefficient matrix W for each layer of each subband according to the subband channel information₂Q. x exp (D), one phase value is subtracted from all the phase coefficients of the nth column of the phase coefficient D of each layer

Obtaining a phase coefficient D 'after phase processing according to W'₂Each subband coefficient after the phase processing is obtained q.

Optionally, the phase value corresponding to the nth column (may be referred to as a phase value for short)

)：

The phase value of the nth column in the phase coefficient matrix or the ith row in the target column, wherein l is an integer greater than or equal to 0; or

The target column may be a preset column, for example: column 1 or column 2, etc. Thus, the phase coefficients of the nth column are all operated with the same phase value.

In addition, due to the phase value

The phase value in the ith row of the nth column in the phase coefficient matrix may be used, so that the phase value in the ith row of each column may be calculated to further improve the correlation of the subband coefficient.

Wherein, the l-th line may be: a row of the phase coefficient matrix is randomly selected. For example:

the phase value can be the phase value of the 1 st column and l th row in a designated D, or the phase value of the n th column and l th row in the D.

Alternatively, the l-th row may be: and the wideband coefficient vector is obtained by calculation according to a bandwidth channel and a beam vector matrix corresponding to the CSI.

Wherein the wideband coefficient vector can be a wideband amplitude coefficient vector, which can be represented by a_WB∈^2L×1That is, the first line may be a_WB∈^2L×1The row number corresponding to the maximum amplitude of the medium coefficient, wherein the beam vector matrix is W₁. In addition, the row corresponding to the maximum coefficient amplitude in the wideband coefficient vector may be a row corresponding to a beam with the maximum wideband coefficient vector amplitude.

The wideband coefficient vector can be calculated as follows:

the terminal calculates the autocorrelation matrix R of each sub-band according to the obtained channel information of each sub-band_nN ∈ {0, K, N-1}, where the autocorrelation matrix R of the wideband channel_wbIs the average of the autocorrelation matrices, i.e. R, of each sub-band channel_wb＝(R₀+…+R_N-1)/N；

To R_wbDecomposing the eigenvalue to obtain the eigenvector e corresponding to the maximum eigenvalue_WB∈^K×1Then the broadband coefficient is

The l-th line is the line corresponding to the maximum coefficient amplitude in the broadband coefficient vector, so that the correlation degree of the subband coefficient is increased, and the compression loss information is further reduced.

In addition, the target phase coefficient matrix may be obtained by calculating coefficients of the subband n according to channel information of the receiving antenna on the subband n, so as to obtain coefficients of each subband.

In this embodiment, a phase value may be implemented

The phase value obtained by subtracting the phase value in the ith row of the nth column of the phase coefficient matrix from the phase value in the ith row of the nth column of the phase coefficient matrix is used, so that the correlation degree of the subband coefficient is increased, and the compression loss information is further reduced.

For example: channel information h on subband n (alternatively referred to as nth subband) according to a certain receiving antenna _n∈^K×1Calculating the coefficients of the sub-band as

Where K represents the number of antenna ports used for data transmission. Similarly, the same method can be adopted to obtain the channel information of each sub-band and calculate the coefficient W' of each sub-band₂＝[w″₀ w″₁…w″_N-1]∈^2L×NAnd may be represented as W ″)₂Q "is the amplitude coefficient of each subband, and D" is the target phase coefficient matrix, specifically including the phase coefficient of each subband. Thereby can realize

It may also be equal to the phase value of the nth column and the ith row of the phase coefficient matrix D minus the phase value of the nth column and the ith row of D ″.

As another optional implementation, the terminal performs preprocessing on the phase corresponding to the subband coefficient to obtain a preprocessed subband coefficient, including:

It should be noted that, since the subband coefficient of the subband n is calculated from the target eigenvector of the subband n, the phase of the target eigenvector of the subband n corresponds to the phase of the subband coefficient of the subband n.

Wherein, the phase value (which may be referred to as phase value for short) corresponding to at least one element in the eigenvector of the subband n to the subband n is described above

) The second operation may be to combine all or part of the elements in the eigenvector of subband n with the phase values respectively

A second operation is performed.

Optionally, the performing, by the terminal, a second operation on at least one element in the feature vector of the subband n and the phase value corresponding to the subband n includes:

Of course, the second operation is not limited to the above, and the phase value may be subtracted from at least one element in the eigenvector of the subband n

Optionally, the phase value corresponding to the subband n is:

In this embodiment, can be according to

Obtaining a complex coefficient with a phase value of

Due to phase values

Is composed of

Thus, the correlation degree of the subband coefficient is increased, and the compression loss information is further reduced.

Of course, the embodiments of the present invention are not limited to the above-mentioned phase values

Is composed of

The phase value of (d), for example: the above phase value

Is composed of

The phase value being equal only

The phase value effect is better.

The above-mentioned method for calculating the subband coefficient of the subband n according to the target eigenvector of the subband n and the beam vector matrix corresponding to the CSI may refer to the eigenvector of the subband n and the beam vector matrix corresponding to the CSI, and is not limited herein.

For example: the terminal can calculate the autocorrelation matrix of each sub-band channel according to the channel information of each sub-band, and then perform eigenvalue decomposition on the autocorrelation matrix of each sub-band channel to obtain a matrix e formed by eigenvectors of each sub-band layer_n∈^K×lN ∈ { 0., N-1}, and l denotes the number of transmission layers.

For each layer of terminals may be according to

Obtaining a complex coefficient with a phase value of

And adding each element in the feature vector of the nth sub-band

Obtaining a matrix e 'formed by the feature vectors of all layers of the nth sub-band'_n∈^K×l,n∈{0,...,N-1}。

The terminal calculates each sub-band feature vector e 'according to the above'_nN ∈ { 0.,. N-1} and a beam vector matrix W₁By passing

The coefficients of the n-th sub-band layers are calculated, and similarly, the sub-band coefficients W 'of the layers are obtained in the same manner'₂＝[w′₀ w′₁…w′_N-1]∈^2L×N。

In this embodiment, the element and phase value in the feature vector of subband n are combined

And performing second operation, so that the characteristic vector of each subband is subjected to second operation with the corresponding phase value when the second operation is performed, thereby increasing the correlation of the coefficients of the adjacent subbands and reducing the compression loss information.

In the embodiment of the present invention, the pretreatment may be performed in units of layers.

As an optional implementation manner, in the case that the Rank corresponding to the CSI is greater than 1, the performing, by the terminal, a first operation on at least one column of the phase coefficient matrix respectively includes:

In this embodiment, the index greater than 1 corresponding to the CSI may be represented by a plurality of layers, and the phase coefficient of the nth column of the phase coefficient matrix of at least one layer of the plurality of layers may be respectively associated with the phase value

The first operation is performed, that is, part or all of the layers may be preprocessed by the first operation, so as to achieve flexible compression to adapt to different scenarios or service requirements.

As an optional implementation manner, when Rank corresponding to the CSI is greater than 1, the second operation is performed by the terminal on at least one element in the feature vector of subband n and a phase value corresponding to the subband n to obtain a target feature vector of subband n, where the second operation includes:

In this embodiment, it can be realized that under the condition of multiple layers, part or all of the layers can be preprocessed by the second operation, so as to realize flexible compression, so as to adapt to different scenes or service requirements.

Further, in the case of multiple layers, all layers may be preprocessed by the first operation or the second operation, or some layers may be preprocessed by the first operation and some other layers may be preprocessed by the second operation.

In the embodiment of the invention, a terminal preprocesses the phase corresponding to the sub-band coefficient to obtain the preprocessed sub-band coefficient; the terminal compresses the preprocessed sub-band coefficient to obtain a compressed coefficient; and the terminal feeds back the CSI corresponding to the compression coefficient to network side equipment. Because the phase is preprocessed before compression, the correlation of the sub-band coefficients can be increased, the compression loss information is less, the accuracy of CSI feedback is improved, the sub-band coefficients can be effectively compressed, and the system performance is improved.

It should be noted that, in the embodiment of the present invention, the subband n may also be referred to as an nth subband, for example: subband 0 may be referred to as the 0 th subband.

The CSI feedback method provided by the embodiment of the present invention is illustrated by a specific example as follows:

let R be 1 for Rank, assuming that the precoding matrix has 2L beams per layer_nRepresenting the n-th subband channel autocorrelation matrix, e_n∈^K×1Channel autocorrelation matrix R representing nth sub-band_nAnd obtaining a characteristic vector corresponding to the maximum characteristic value after characteristic value decomposition, wherein K represents the number of antenna ports used for data transmission. The nth subband coefficient of

The subband coefficient matrix over the entire system bandwidth may be represented as W₂＝[w₀ w₁…w_N-1]∈^2L×N. Coefficient of each subband W₂Can be expressed in the form of a dot product of an amplitude coefficient and a phase coefficient, i.e. W₂Q. x exp (D), where Q and D represent amplitude and phase coefficients, respectively, which may be expressed as:

example 1:

for the first operation, for Rank being 1, the method may further include the following steps:

let each column element of the phase coefficient D subtract the element corresponding to the l-th row in the column, and assuming that l is 0, the phase coefficient D' after the phase processing can be expressed as follows:

And calculating each sub-band coefficient W 'according to D'₂Q. × exp (D'), and then using the compressed base vector W_fThe compressed coefficients of each sub-band can be obtained

According to

And calculating the codebook used by the terminal.

Example 2:

the terminal calculates the autocorrelation matrix R of each sub-band according to the obtained channel information of each sub-band_nN is the {0, K, N-1}, autocorrelation matrix R of the wideband channel_wbIs the average of the autocorrelation matrices, i.e. R, of each sub-band channel_wb＝(R₀+…+R_N-1)/N。

Coefficient of each subband W₂Can be expressed as a dot product of amplitude and phase coefficients, i.e. W₂Q. x exp (D), where Q and D represent amplitude and phase coefficients, respectively, which may be expressed as:

suppose a wideband magnitude coefficient vector a_WBThe beam with the maximum amplitude is the second beam, and the element corresponding to the second row in the column is subtracted from each column element of the phase coefficient D, so that the phase coefficient D' after the phase processing is expressed as follows:

calculating each subband coefficient W 'according to D'₂Q. × exp (D'), and then using the compressed base vector W _fThe compressed coefficients of each sub-band can be obtained

According to

And calculating the codebook used by the terminal.

Example 3:

let the element corresponding to the l-th row in the 1 st column be subtracted from each column element of the phase coefficient D, and assuming that l is 0, the phase coefficient D' after the phase processing can be expressed as follows:

According to

And calculating the codebook used by the terminal.

Example 4:

suppose that the channel information of the nth sub-band on a certain antenna of the terminal is h_n∈^K×1Then the nth subband coefficient is

Where K represents the number of antenna ports used for data transmission. Each subband coefficient across the entire system bandwidth may be denoted as W ″₂＝[w″₀ w″₁…w″_N-1]∈^2L×N. Coefficient of each subband W ″)₂Also expressed as the dot product of the amplitude coefficient and the phase coefficient, i.e. W ″₂Q ". times exp (D"), where Q "and D" respectively denote according to channel information h _nObtaining an amplitude coefficient and a phase coefficient, wherein the phase coefficient can be expressed as:

subtracting the phase value corresponding to the first row in the phase coefficient D' from all the phases in the first row in the phase coefficient D to obtain N phase values

Let l equal 0. Then all the phase coefficients in the nth column of the phase coefficient D are subtracted

The phase coefficient D' after the available phase processing is expressed as follows:

According to

And calculating the codebook used by the terminal.

Example 5:

for the second operation, for Rank being 1, the method may further include the following steps of:

for the nth sub-band, the terminal passes

Calculating to obtain a complex coefficient with a corresponding phase value of

Adding the phase of each element in the eigenvector of the nth sub-band

The n sub-band characteristic vector after phase processing can be obtained

Then according to

The combining coefficient of the nth subband is calculated.

According to the two steps, the combined coefficient of other sub-bands can be calculated, and the coefficient matrix W 'of each sub-band after phase processing is obtained' ₂. Reusing compressed basis vector W_fThe compressed coefficients of each sub-band can be obtained

According to

And calculating the codebook used by the terminal.

Referring to fig. 3, fig. 3 is a flowchart of a CSI receiving method according to an embodiment of the present invention, as shown in fig. 3, including the following steps:

It should be noted that, the above preprocessing may refer to the corresponding description of the embodiment shown in fig. 2, which is not described herein again, and the same beneficial effects may be achieved.

In addition, the network side device may further indicate, to the terminal, codebook parameter information of the CSI, and the CSI codebook generated by the terminal may be generated according to the parameter information.

Further, the method further comprises:

the network side device analyzes the CSI to obtain the compressed coefficient information of the compressed coefficient, and may further obtain compressed base vector indication information and orthogonal beam indication information. Wherein, the compressed base vector indication information may be a compressed base vector W _fThe orthogonal beam indication information may be a beam vector matrix W₁The indication information of (2).

The network side equipment obtains a quantized compression coefficient according to the compression coefficient information

And respectively obtaining a compressed base vector W according to the compressed base vector indication information and the orthogonal beam indication information_fAnd the beam vector matrix W₁；

And according to the above-mentioned compression coefficient

And a compressed base vector W_fTo obtain a subband coefficient matrix W₂For example: according to

Obtaining a subband coefficient matrix W₂；

Then, according to the beam vector matrix W₁The CSI codebook used by the terminal can be calculated.

It should be noted that, this embodiment is used as an implementation of the network side device corresponding to the embodiment shown in fig. 2, and specific implementation thereof may refer to the relevant description of the embodiment shown in fig. 2, so that, in order to avoid repeated description, the embodiment is not described again, and the same beneficial effects may also be achieved.

Referring to fig. 4, fig. 4 is a structural diagram of a terminal according to an embodiment of the present invention, and as shown in fig. 4, the terminal 400 includes:

a processing module 401, configured to pre-process a phase corresponding to a subband coefficient to obtain a pre-processed subband coefficient;

a compression module 402, configured to compress the preprocessed sub-band coefficients to obtain compressed coefficients;

A feedback module 403, configured to feed back CSI corresponding to the compression coefficient to a network side device.

Optionally, the subband coefficients include a phase coefficient matrix, and the processing module 401 is configured to perform a first operation on at least one column of the phase coefficient matrix to obtain preprocessed subband coefficients, where the first operation on an nth column is to perform a first operation on at least one phase coefficient of the nth column and a phase value corresponding to the nth column, and N is ∈ { 0., N-1}, where N represents a number of subbands.

Optionally, the processing module 401 is configured to perform a first operation on all columns of the phase coefficient matrix respectively to obtain preprocessed subband coefficients, where the first operation on the nth column is to subtract at least one phase coefficient of the nth column from a phase value corresponding to the nth column, respectively.

Optionally, the phase value corresponding to the nth column is:

Optionally, the l-th action:

a row selected randomly in the phase coefficient matrix; or alternatively

Optionally, as shown in fig. 5, the processing module 401 includes:

the first calculating unit 4011 is configured to perform a second operation on at least one element in the feature vector of the subband N and the phase value corresponding to the subband N, so as to obtain a target feature vector of the subband N, where N is an element of { 0.,. N-1}, and N represents a subband number;

the second calculating unit 4012 is configured to calculate a subband coefficient of the subband n according to the target eigenvector of the subband n and the beam vector matrix corresponding to the CSI.

Optionally, the first calculating unit 4011 is configured to add at least one element in the feature vector of the subband n to the phase value corresponding to the subband n.

Optionally, the phase value corresponding to the subband n is:

Optionally, the processing module 401 is configured to respectively perform a first operation on at least one column of the phase coefficient matrix of at least one layer when the Rank corresponding to the CSI is greater than 1.

Optionally, when Rank corresponding to the CSI is greater than 1, the processing module 401 is configured to perform a second operation on at least one element of the subband n in the feature vector of at least one layer and a phase value corresponding to the subband n, so as to obtain a target feature vector of the subband n.

It should be noted that, in this embodiment, the terminal 400 may be any implementation manner of the method embodiment in the present invention, and any implementation manner of the terminal in the method embodiment in the present invention may be implemented by the terminal 400 in this embodiment, and achieve the same beneficial effects, which is not described herein again.

Referring to fig. 6, fig. 6 is a structural diagram of a network side device according to an embodiment of the present invention, and as shown in fig. 6, the network side device 600 includes:

a receiving module 601, configured to receive CSI fed back by a terminal, where a compression coefficient corresponding to the CSI is a compression coefficient obtained by preprocessing a phase corresponding to a subband coefficient by the terminal and compressing the preprocessed subband coefficient.

It should be noted that, in this embodiment, the network-side device 600 may be a terminal of any implementation manner in the method embodiment of the present invention, and any implementation manner of the network-side device in the method embodiment of the present invention may be implemented by the network-side device 600 in this embodiment, and the same beneficial effects are achieved, and details are not described here.

Referring to fig. 7, fig. 7 is a structural diagram of another terminal according to an embodiment of the present invention, and as shown in fig. 7, the terminal includes: a transceiver 710, a memory 720, a processor 700, and a program stored on the memory 720 and executable on the processor 700, wherein:

the transceiver 710 is configured to perform preprocessing on a phase corresponding to a subband coefficient to obtain a preprocessed subband coefficient; compressing the preprocessed sub-band coefficient to obtain a compressed coefficient; feeding back CSI corresponding to the compression coefficient to network side equipment;

alternatively, the first and second electrodes may be,

the processor 700 is configured to pre-process a phase corresponding to a subband coefficient to obtain a pre-processed subband coefficient; compressing the preprocessed sub-band coefficient to obtain a compressed coefficient;

the transceiver 710 is configured to feed back CSI corresponding to the compression factor to a network side device.

The transceiver 710 may be used for receiving and transmitting data under the control of the processor 700.

In FIG. 7, the bus architecture may include any number of interconnected buses and bridges, with various circuits being linked together, particularly one or more processors represented by processor 700 and memory represented by memory 720. 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 transceiver 710 may be a number of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium.

The processor 700 is responsible for managing the bus architecture and general processing, and the memory 720 may store data used by the processor 700 in performing operations.

It should be noted that the memory 720 is not limited to being on the terminal, and the memory 720 and the processor 700 may be separated in different geographical locations.

Optionally, the performing a first operation on at least one column of the phase coefficient matrix respectively includes:

Optionally, the phase value corresponding to the nth column is:

The phase value of the nth column in the phase coefficient matrix or the l th row in the target column, l is an integer greater than or equal to 0; or alternatively

Optionally, the l-th action:

a row is randomly selected from the phase coefficient matrix; or

Optionally, the phase value corresponding to the subband n is:

phase value of (a), wherein_nFeature vector representing subband n, e₀Representing the feature vector for subband 0.

Optionally, when the Rank corresponding to the CSI is greater than 1, respectively performing a first operation on at least one column of the phase coefficient matrix, where the first operation includes:

and respectively executing a first operation on at least one column of the phase coefficient matrix of at least one layer.

Optionally, when Rank corresponding to the CSI is greater than 1, performing a second operation on at least one element in the feature vector of the subband n and the phase value corresponding to the subband n to obtain a target feature vector of the subband n, where the second operation includes:

and performing second operation on at least one element of the subband n in the feature vector of at least one layer and the phase value corresponding to the subband n to obtain a target feature vector of the subband n.

It should be noted that, the terminal in this embodiment may be any implementation manner of the method embodiment in the present invention, and any implementation manner of the terminal in the method embodiment in the present invention may be implemented by the terminal in this embodiment, and the same beneficial effects are achieved, and details are not described here again.

Referring to fig. 8, fig. 8 is a structural diagram of another network side device according to an embodiment of the present invention, and as shown in fig. 8, the network side device includes: a transceiver 810, a memory 820, a processor 800, and a program stored on the memory 820 and executable on the processor, wherein:

the transceiver 810 is configured to receive CSI fed back by a terminal, where a compression coefficient corresponding to the CSI is a compression coefficient obtained by preprocessing a phase corresponding to a subband coefficient by the terminal and compressing the preprocessed subband coefficient.

Transceiver 810 may be used, among other things, to receive and transmit data under the control of processor 800.

In fig. 8, the bus architecture may include any number of interconnected buses and bridges, with various circuits being linked together, particularly one or more processors represented by processor 800 and memory represented by memory 820. 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 transceiver 810 may be a number of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium.

The processor 800 is responsible for managing the bus architecture and general processing, and the memory 820 may store data used by the processor 800 in performing operations.

It should be noted that the memory 820 is not limited to be on the terminal, and the memory 820 and the processor 800 may be separated in different geographical locations.

It should be noted that, in this embodiment, the network-side device may be a network-side device in any implementation manner in the method embodiment of the present invention, and any implementation manner of the network-side device in the method embodiment of the present invention may be implemented by the network-side device in this embodiment, so as to achieve the same beneficial effects, and details are not described here.

In the several embodiments provided in the present application, it should be understood that the disclosed method and apparatus may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may be physically included alone, or two or more units may be integrated into one unit. The integrated unit can be realized in a form of hardware, or in a form of hardware plus a software functional unit.

The integrated unit implemented in the form of a software functional unit may be stored in a computer readable storage medium. The software functional unit is stored in a storage medium and includes several instructions to enable a computer device (which may be a personal computer, a server, or a network device) to execute some steps of the processing method of the information data block according to various embodiments of the present invention. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A method for feeding back Channel State Information (CSI), comprising:

the terminal feeds back the CSI corresponding to the compression coefficient to network side equipment;

the method for preprocessing the phase corresponding to the sub-band coefficient by the terminal to obtain the preprocessed sub-band coefficient includes:

the terminal respectively executes first operation on at least one column of a phase coefficient matrix to obtain preprocessed subband coefficients, wherein the first operation on an nth column is to perform first operation on at least one phase coefficient of the nth column and a phase value corresponding to the nth column, N belongs to { 0.,. N-1}, N represents the number of subbands, and the subband coefficients comprise the phase coefficient matrix; or

The terminal respectively carries out second operation on at least one element in the characteristic vector of the subband N and the phase value corresponding to the subband N to obtain a target characteristic vector of the subband N, wherein N belongs to { 0.,. N-1}, and N represents the number of the subbands; and the terminal calculates the subband coefficient of the subband n according to the target characteristic vector of the subband n and the beam vector matrix corresponding to the CSI.

2. The method of claim 1, wherein the terminal performs a first operation on at least one column of the phase coefficient matrix, respectively, comprising:

3. The method of claim 1 or 2, wherein the nth column corresponds to a phase value of:

4. The method of claim 3, wherein the l-th action:

a row is randomly selected from the phase coefficient matrix; or

5. The method of claim 1, wherein the terminal performs a second operation on at least one element in the eigenvector of subband n and the phase value corresponding to subband n, and comprises:

and the terminal respectively adds the phase value corresponding to the subband n to at least one element in the characteristic vector of the subband n.

6. The method of claim 1 or 5, wherein the subband n corresponds to a phase value of:

7. The method of claim 1, wherein in a case that the Rank corresponding to the CSI is greater than 1, the terminal respectively performs a first operation on at least one column of the phase coefficient matrix, including:

8. The method of claim 1, wherein in a case that Rank corresponding to the CSI is greater than 1, the second operation is performed by the terminal on at least one element in the eigenvector of subband n and a phase value corresponding to the subband n to obtain a target eigenvector of subband n, including:

9. A CSI receiving method, comprising:

network side equipment receives CSI fed back by a terminal, wherein a compression coefficient corresponding to the CSI is a compression coefficient obtained by preprocessing a phase corresponding to a sub-band coefficient by the terminal and compressing the preprocessed sub-band coefficient;

the compression coefficient corresponding to the CSI comprises: the terminal respectively executes first operation on at least one column of a phase coefficient matrix and compresses the obtained preprocessed sub-band coefficients to obtain compressed coefficients, wherein the first operation of the nth column is to perform first operation on at least one phase coefficient of the nth column and a phase value corresponding to the nth column, N belongs to { 0.,. multidot.N-1 }, N represents the number of sub-bands, and the sub-band coefficients comprise the phase coefficient matrix; or

The compression coefficient corresponding to the CSI comprises: and compressing the sub-band coefficient of the sub-band n to obtain a compressed coefficient, wherein the sub-band coefficient of the sub-band n is obtained by the following steps:

The terminal respectively carries out second operation on at least one element in the characteristic vector of the sub-band N and the phase value corresponding to the sub-band N to obtain a target characteristic vector of the sub-band N, wherein N belongs to { 0., N-1}, and N represents the number of the sub-bands; and the terminal calculates the subband coefficient of the subband n according to the target characteristic vector of the subband n and the beam vector matrix corresponding to the CSI.

10. A terminal, comprising:

the feedback module is used for feeding back the CSI corresponding to the compression coefficient to network side equipment;

the subband coefficients comprise phase coefficient matrixes, the processing module is used for respectively executing first operation on at least one column of the phase coefficient matrixes to obtain preprocessed subband coefficients, the first operation on the nth column is to respectively perform first operation on at least one phase coefficient of the nth column and a phase value corresponding to the nth column, N belongs to { 0., N-1}, and N represents the number of subbands; or

The processing module comprises:

11. The terminal of claim 10, wherein the processing module is configured to perform a first operation on all columns of the phase coefficient matrix to obtain preprocessed subband coefficients, and wherein the first operation on an nth column is to subtract at least one phase coefficient of the nth column by a phase value corresponding to the nth column.

12. The terminal of claim 10, wherein the processing module is configured to add at least one element of the eigenvector of subband n to the phase value corresponding to subband n, respectively.

13. A network-side device, comprising:

the terminal comprises a receiving module and a compressing module, wherein the receiving module is used for receiving the CSI fed back by the terminal, and the compressing coefficient corresponding to the CSI is a compressing coefficient obtained by preprocessing the phase corresponding to the subband coefficient by the terminal and compressing the preprocessed subband coefficient;

Wherein, the compression coefficient corresponding to the CSI comprises: the terminal respectively executes first operation on at least one column of a phase coefficient matrix and compresses the obtained preprocessed sub-band coefficients to obtain compressed coefficients, wherein the first operation of the nth column is to perform first operation on at least one phase coefficient of the nth column and a phase value corresponding to the nth column, N belongs to { 0.,. multidot.N-1 }, N represents the number of sub-bands, and the sub-band coefficients comprise the phase coefficient matrix; or alternatively

14. A terminal, comprising: a transceiver, a memory, a processor, and a program stored on the memory and executable on the processor,

alternatively, the first and second electrodes may be,

the transceiver is configured to feed back CSI corresponding to the compression factor to a network side device;

wherein, the preprocessing the phase corresponding to the sub-band coefficient to obtain the preprocessed sub-band coefficient includes:

performing first operation on at least one column of a phase coefficient matrix respectively to obtain preprocessed subband coefficients, wherein the first operation on an nth column is to perform first operation on at least one phase coefficient of the nth column and a phase value corresponding to the nth column respectively, N belongs to { 0.,. N-1}, and N represents the number of subbands and the subband coefficients comprise the phase coefficient matrix; or

Performing second operation on at least one element in the feature vector of the subband N and the phase value corresponding to the subband N to obtain a target feature vector of the subband N, wherein N belongs to { 0.,. N-1}, and N represents the number of the subbands; and calculating the subband coefficient of the subband n according to the target characteristic vector of the subband n and the beam vector matrix corresponding to the CSI.

15. The terminal of claim 14, wherein the performing the first operation on at least one column of the phase coefficient matrix comprises:

16. The terminal of claim 14, wherein performing the second operation on at least one element in the eigenvector of subband n and the phase value corresponding to subband n comprises:

17. A network-side device, comprising: a transceiver, a memory, a processor, and a program stored on the memory and executable on the processor,

the transceiver is used for receiving CSI fed back by a terminal, wherein a compression coefficient corresponding to the CSI is a compression coefficient obtained by preprocessing a phase corresponding to a subband coefficient by the terminal and compressing the preprocessed subband coefficient;

18. A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the steps in the CSI feedback method according to any of claims 1 to 8, or which, when being executed by a processor, carries out the steps in the CSI receiving method according to claim 9.