WO2023236535A1

WO2023236535A1 - Beamforming method and apparatus for channel state information-reference signal (csi-rs), and storage medium

Info

Publication number: WO2023236535A1
Application number: PCT/CN2023/070706
Authority: WO
Inventors: 王朝阳
Original assignee: 中兴通讯股份有限公司
Priority date: 2022-06-10
Filing date: 2023-01-05
Publication date: 2023-12-14
Also published as: CN117254839A

Abstract

The present disclosure relates to a beamforming method and apparatus for a CSI-RS, and a storage medium. The method comprises: determining a frequency-domain forming vector based on a frequency-domain basis vector; multiplying, by the frequency-domain forming vector, a CSI-RS to be transmitted, so as to obtain a product result, wherein the product result is used for aligning a phase in a frequency domain corresponding to the maximum path timing advance (TA), so as to compensate for the maximum path TA; and multiplying the product result by a space-domain weight matrix, so as to perform beamforming on said CSI-RS.

Description

Beamforming method, device and storage medium for channel state reference signal

Cross-references to related applications

This disclosure claims priority to Chinese patent application CN202210657932.8 titled "Beamforming Method, Device and Storage Medium for Channel State Reference Signal" submitted on June 10, 2022, the entire content of which is incorporated into this disclosure by reference. middle.

Technical field

The present disclosure relates to the field of communications, and in particular, to a beamforming method, device and storage medium for a channel state reference signal.

Background technique

In wireless communication systems, the feedback of channel state information (Channel State Information, CSI) mainly relies on the channel estimation results of the channel state reference signal (Channel State Information-Reference Signal, CSI-RS). The user terminal (User Euipment, UE) obtains the CSI-RS configuration through wireless signaling, instructs it to perform channel quality estimation at the corresponding CSI-RS resource location, and selects the optimal Rank Indicator (Rank Indicator) based on the channel estimation results. RI), Precoding Matrix Indicator (PMI), and Channel Quality Indicator (CQI) are fed back to the base station (Base Station, BS). The base station performs resource allocation and beam management on each channel based on the above feedback information. Therefore, more accurate CSI-RS channel estimation results directly affect the accuracy of the channel information indicators fed back by the UE to the base station, allowing the base station to obtain feedback information with higher accuracy, thereby improving the reliability of resource allocation and beam management, and improving the communication system. overall performance.

In existing research on improving the accuracy of CSI-RS channel estimation, there is a technical problem that it is difficult to meet the needs of downlink channel services through shaping optimization only in the airspace.

Contents of the invention

The present disclosure provides a beamforming method, device and storage medium for a channel state reference signal to solve the technical problem in some cases that it is difficult to meet the needs of downlink channel services by only forming optimization in the air domain.

In a first aspect, the present disclosure provides a beamforming method for a channel state reference signal, which includes: determining a frequency domain shaping vector based on a frequency domain base vector; multiplying the CSI-RS to be transmitted and the frequency domain shaping vector to obtain The product result, where the product result is used to align the phase in the frequency domain corresponding to the maximum diameter timing advance TA to compensate the maximum diameter TA; the product result is multiplied by the spatial domain weight matrix to obtain the CSI-RS to be transmitted Perform beamforming.

In a second aspect, the present disclosure provides a beamforming device for a channel state reference signal, including: a determination module for determining a frequency domain shaping vector based on a frequency domain base vector; a first processing module for converting the to-be-transmitted The CSI-RS is multiplied by the frequency domain shaping vector to obtain a product result, in which the product result is used to align the phases in the frequency domain corresponding to the maximum diameter timing advance TA to compensate for the maximum diameter TA; the second processing module uses The product result is multiplied by the spatial domain weight matrix to perform beamforming on the CSI-RS to be transmitted.

In a third aspect, an electronic device is provided, including a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory complete communication with each other through the communication bus; the memory is used to store computer programs; and the processing The processor is used to implement the method steps of any embodiment of the first aspect when executing a program stored in the memory.

A fourth aspect provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the method steps of any embodiment of the first aspect are implemented.

Description of the drawings

The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate embodiments consistent with the disclosure and together with the description, serve to explain the principles of the disclosure.

In order to more clearly illustrate the present disclosure or the technical solutions in some situations, the following will briefly introduce the embodiments or the drawings that need to be used in some situations. Obviously, for those of ordinary skill in the art, without paying any attention to Under the premise of creative labor, other drawings can also be obtained based on these drawings.

Figure 1 is a schematic flow chart of a CSI-RS beamforming method provided by the present disclosure;

Figure 2 is a schematic structural diagram of a CSI-RS beamforming device provided by the present disclosure;

Figure 3 is a schematic structural diagram of an electronic device provided by the present disclosure.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the technical solutions in the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings in the present disclosure. Obviously, the described embodiments are part of the implementation of the present disclosure. examples, not all examples. Based on the embodiments in this disclosure, all other embodiments obtained by those of ordinary skill in the art without any creative efforts fall within the scope of protection of this disclosure.

Figure 1 is a schematic flowchart of a CSI-RS beamforming method provided by the present disclosure. As shown in Figure 1, the steps of the method include steps 102 to 106.

Step 102: Determine the frequency domain shaping vector based on the frequency domain basis vector. Step 104: Multiply the CSI-RS to be transmitted and the frequency domain shaping vector to obtain a product result. The product result is used to align the phase in the frequency domain corresponding to the maximum diameter timing advance TA to compensate for the maximum diameter TA. . Step 106: Multiply the product result with the spatial domain weight matrix to perform beamforming on the CSI-RS to be transmitted.

Through the above steps 102 to 106, the CSI-RS and the frequency domain shaping vector can be multiplied first, and the product result can be used to align the phase in the frequency domain corresponding to the maximum diameter timing advance TA, so as to adjust the maximum diameter TA. compensation, and then multiplies the product result with the spatial domain weight matrix, realizing the use of the phase information of the uplink channel estimation result, constructing a matching frequency domain basis vector, completing the beamforming of CSI-RS, and realizing the The phase pre-compensation of the maximum diameter TA in the frequency domain dimension on the base station side improves the accuracy of the base station's shaping and control of downlink services, thus improving the performance of the communication system and solving the difficulty of shaping optimization only in the air domain in some cases. Technical issues to meet the needs of downlink channel services.

It should be noted that the execution subject in this disclosure is a network-side device, such as a base station; therefore, after beamforming the CSI-RS to be transmitted, the base station can send the beamformed CSI-RS to the terminal. Since the phase compensation is performed in the frequency domain by multiplying the CSI-RS by the frequency domain shaping vector at the transmitter, in the scenario where the channel condition is dominated by the LOS path, the signal received by the terminal has only a small TA, which can improve the CSIRS channel estimation. The accuracy is improved, thereby improving the reliability of indicators such as RI, PMI, and CQI fed back from the terminal side to the base station.

In this disclosure, the method of determining the frequency domain shaping vector based on the frequency domain base vector involved in the above step 102 may further include steps 11 to 14.

Step 11: Perform summation processing on the signal estimation matrices corresponding to the channel sounding reference signal SRS in the antenna dimension and port dimension respectively to obtain the summation result. Step 12: Merge resource blocks RB on the summation results based on frequency domain granularity to obtain the first merging result. Step 13: Perform inner product and modulus of the first combined result with each frequency domain basis vector to obtain multiple modulus results. Step 14: Determine the frequency domain shaping vector based on the frequency domain basis vector corresponding to the maximum value among the multiple modular results.

Through the above steps 11 to 14, in order to further improve the accuracy of channel estimation, the signal estimation matrix can be summed in the antenna dimension and port dimension respectively to obtain a more accurate combination in the antenna dimension and port dimension. As a result, the combined result and each frequency domain basis vector are subsequently performed as an inner product and modulo is obtained to obtain multiple modulo results, and then the frequency domain is determined based on the frequency domain basis vector corresponding to the maximum value among the multiple modulo results. The shaping vector, the determined frequency domain shaping vector is the optimal frequency domain shaping vector, that is, the frequency domain shaping vector has the highest phase matching degree with the channel estimation result to complete the CSI-RS beamforming , to achieve phase pre-compensation of the maximum diameter TA in the frequency domain dimension at the base station side.

In an exemplary embodiment, the method of determining the frequency domain shaping vector based on the frequency domain basis vector corresponding to the maximum value among the multiple modeling results involved in the above step 14 may further include steps 21 and 22.

Step 21: Perform RB expansion on the frequency domain basis vector corresponding to the maximum value among the multiple modulo results. Step 22: Determine the expanded frequency domain basis vector as a frequency domain shaping vector.

It should be noted that the frequency domain dimension K after the above-mentioned RB expansion of the frequency domain basis vector corresponding to the maximum value among the multiple modulo results is related to the bandwidth, which is the number of RBs.

In an optional implementation of the present disclosure, the method of the present disclosure may further include step 31 before performing an inner product with each frequency domain basis vector on the first combined result and taking the modulo to obtain multiple modulo results.

Step 31: Generate frequency domain basis vectors equal to the number of angle division granularities based on the angle division granularity and the frequency domain granularity; wherein the angle division granularity is the number of equal shares of the preset angle.

Among them, the preset angle can be 2π. The larger the value of the angle division granularity, the finer the angle 2π is divided, and the higher the accuracy of frequency domain phase compensation.

In one embodiment of the present disclosure, the method of performing summation processing on the signal estimation matrices corresponding to the SRS in the antenna dimension and the port dimension to obtain the summation result involved in the above step 11 may further include step 41 and Step 42.

Step 41: Merge the signal estimation matrices corresponding to the SRS in the antenna dimension to obtain a second merging result. Step 42: Merge the second merging results in the port dimension to obtain a third merging result, where the third merging result is the summation result.

That is to say, in this disclosure, the signal estimation matrices are first combined in the antenna dimension, and then combined in the port dimension, so that the optimal frequency domain shaping vector can be found more accurately later.

The present disclosure will be illustrated below with reference to the specific implementation mode of the present disclosure. The specific implementation mode provides a CSI-RS shaping optimization method. This method achieves by multiplying the base station originating CSI-RS signal by a frequency domain shaping vector. Phase compensation in the frequency domain, and then aligning the phases in the frequency domain corresponding to the maximum diameter TA, to achieve pre-compensation of the maximum diameter TA. Specifically, the shaped frequency domain data can be determined through the following expression:

y(f)=Ww _opt x(f)

Among them, y(f) is the CSI-RS after shaping, x(f) is the CSI-RS to be shaped, W is the spatial domain weight matrix, and w _opt is the frequency domain shaping vector.

In addition, the frequency domain shaping vector is the optimal frequency domain basis vector selected by finding the maximum value of the multiplication of the uplink srsH and all frequency domain basis vectors respectively. The frequency domain basis vector is a vector with ρ as the granularity, equal phase intervals, and the dimension is the number of RBs (K); where ρ represents the frequency domain granularity, and the value is a positive integer. When it is 1, the frequency domain of the frequency domain basis vector The direction accuracy is divided into the finest. The method steps of this specific embodiment include steps 201 to 211.

Step 201: Generate M frequency domain basis vectors w _i according to the angular division granularity M and the frequency domain granularity ρ.

Among them, the frequency domain basis vector can be generated according to the following expression:

Among them, w is the frequency domain basis vector, l is the RB group index, and K is the number of RBs;

The angle division granularity M is defined as the fraction of the equal division angle 2π. The larger the value of M, the smaller the angle 2π is divided, and the higher the accuracy of frequency domain phase compensation. The angle group θ _i is expressed as:

Among them, i is the angle index of the angle group, and θ _i is the i-th angle.

M frequency domain basis vector groups are expressed as:

Among them, w _i is the i-th frequency domain basis vector.

Step 202: Combine the channel estimation matrices H _SRS of SRS in the antenna dimension.

Step 203: Merge the results of step 202 in the port dimension.

Among them, SrsH is summed in the antenna and port dimensions respectively. The dimension of SrsH is: number of RBs × number of antennas Rx × number of ports Tx. Expressed as:

H _SRS = [H ₀ H ₁ ... H _K-1 ]

Among them, H of each RB is a matrix of Rx times Tx:

Among them, k is the RB index, Rx is the number of physical antennas, and Tx is the number of antenna ports.

By accumulating the physical antenna and port dimensions of H _k respectively, we can get:

Therefore, the summation of SrsH results in a vector of dimension K:

Step 204: Perform RB merging on the result of step 203 according to the frequency domain granularity ρ.

Among them, according to the granularity of frequency domain basis vector design, H is merged into RBs for each ρ, and the dimension is

The result is recorded as:

Step 205: Make an inner product of the result of step 204 and the i-th frequency domain basis vector and record the result.

Step 206: The loop index value i is incremented by 1, and it is judged whether i is less than M. If the judgment result is yes, return to step 205; if the judgment result is no, execute step 207.

Among them, do inner products with M frequency domain basis vectors and find the modulus. The result of traversing the modulus is:

Step 207: Select the frequency domain basis vector corresponding to the maximum value of the modulus result as the optimal frequency domain basis vector.

Among them, find the frequency domain basis vector corresponding to the maximum value and perform RB expansion as the optimal frequency domain basis vector, through the following expression:

Step 208: Perform RB expansion on the optimal frequency domain basis vector to obtain a frequency domain shaped vector, where the frequency domain dimension after expansion is K.

Step 209: The CSI-RS signal is multiplied by the frequency domain shaping vector to complete the pre-compensation of the maximum diameter TA in the frequency domain.

Step 210: Multiply the result of step 9 by the spatial domain weight matrix W to complete beamforming.

Step 211: Send the shaped CSI-RS.

Through the above-mentioned CSI-RS signal shaping optimization method in steps 201 to 211, in the wireless communication system, the CSI-RS signal is multiplied by the frequency domain shaping vector at the transmitting end to perform phase compensation in the frequency domain. In a scenario where the channel condition is dominated by the LOS path, the signal received by the terminal has only a small TA, which can improve the accuracy of CSI-RS channel estimation, thereby improving the reliability of the RI, PMI, CQI and other indicators fed back by the terminal side to the base station. , improves the accuracy of shaping and control of downlink services by the transmitter, and improves the performance of the communication system. In addition, since the signal received by the terminal removes the influence of large TA, it can also make the terminal CSI-RS channel estimation algorithm More optimized.

Corresponding to the method in Figure 1 mentioned above, the present disclosure also provides a CSI-RS beamforming device. As shown in Figure 2 , the device includes a determination module 22, a first processing module 24, and a second processing module 26.

The determination module 22 is used to determine the frequency domain shaping vector based on the frequency domain basis vector. The first processing module 24 is used to multiply the CSI-RS to be transmitted and the frequency domain shaping vector to obtain a product result, where the product result is used to align the phase in the frequency domain corresponding to the maximum diameter timing advance TA, so as to The maximum diameter TA is compensated. The second processing module 26 is used to multiply the product result by the spatial domain weight matrix to perform beamforming on the CSI-RS to be transmitted.

Through the device in this disclosure, the CSI-RS can be multiplied by the frequency domain shaping vector first. The product result can be used to align the phase in the frequency domain corresponding to the maximum diameter timing advance TA to compensate for the maximum diameter TA. , and then multiply the product result with the spatial domain weight matrix to realize the use of the phase information of the uplink channel estimation result to construct a matching frequency domain basis vector, complete the beamforming of CSI-RS, and realize the The phase pre-compensation of the maximum diameter TA in the frequency domain dimension improves the accuracy of the base station's shaping and control of downlink services, thereby improving the performance of the communication system and solving the problem of insufficiency of shaping optimization in the air domain in some cases. Technical issues related to the requirements of downlink channel services.

In an exemplary embodiment, the determination module 22 in the present disclosure may further include: a first processing unit configured to perform summation processing on the signal estimation matrix corresponding to the channel sounding reference signal SRS in the antenna dimension and the port dimension respectively, Obtain the summation result; the merging unit is used to merge the resource blocks RB of the summation result based on the frequency domain granularity to obtain the first merging result; the second processing unit is used to combine the first merging result with each frequency domain basis vector Do the inner product to obtain multiple modular results; the determination unit is used to determine the frequency domain shaping vector based on the frequency domain basis vector corresponding to the maximum value among the multiple modular results.

In an exemplary embodiment, the determination unit in the present disclosure may further include: an expansion subunit, configured to perform RB expansion on the frequency domain basis vector corresponding to the maximum value in multiple modulo results; a determination subunit, configured to The expanded frequency domain basis vector is determined as the frequency domain shaping vector.

In an exemplary embodiment, the device in the present disclosure may further include: a generating module, configured to perform an inner product on the first merging result with each frequency domain basis vector respectively to obtain multiple modulo results, based on the angle The division granularity and frequency domain granularity generate frequency domain basis vectors equal to the number of angle division granularities; where the angle division granularity is the number of equal shares of the preset angle.

In an exemplary embodiment, the first processing unit in the present disclosure may further include: a first merging sub-unit, used to merge the signal estimation matrix corresponding to the SRS in the antenna dimension to obtain a second merging result; The merging subunit is used to merge the second merging results in the port dimension to obtain the third merging result, where the third merging result is the summation result.

As shown in Figure 3, the present disclosure provides an electronic device, including a processor 111, a communication interface 112, a memory 113, and a communication bus 114. The processor 111, the communication interface 112, and the memory 113 complete interactions with each other through the communication bus 114. Communication, memory 113, used to store computer programs.

In one embodiment of the present disclosure, the processor 111 is used to implement the CSI-RS beamforming method provided in any of the foregoing method embodiments when executing the program stored on the memory 113. Its function is also similar. Here No longer.

The present disclosure also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of the CSI-RS beamforming method as provided in any of the foregoing method embodiments are implemented.

The above technical solution provided by the present disclosure has the following advantages compared with some situations: the method provided by the present disclosure can first multiply the CSI-RS and the frequency domain shaping vector, and the product result can be configured to align the maximum diameter timing The advance TA corresponds to the phase in the frequency domain to compensate for the maximum diameter TA, and then the product result is multiplied with the spatial domain weight matrix to realize the use of the phase information of the uplink channel estimation result to construct a matching frequency domain basis. Vector, completes the beamforming of CSI-RS, realizes the phase pre-compensation of the maximum diameter TA in the frequency domain dimension on the base station side, improves the accuracy of the base station's shaping and control of downlink services, thereby improving the communication system performance, solving the technical problem that in some cases it is difficult to meet the needs of downlink channel services through shaping optimization only in the airspace.

It should be noted that in this article, relational terms such as “first” and “second” are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply these There is no such actual relationship or sequence between entities or operations. Furthermore, the terms "comprises," "comprises," or any other variations thereof are intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus that includes a list of elements includes not only those elements, but also those not expressly listed other elements, or elements inherent to the process, method, article or equipment. Without further limitation, an element defined by the statement "comprises a..." does not exclude the presence of additional identical elements in a process, method, article, or apparatus that includes the stated element.

The above are only specific embodiments of the present disclosure, enabling those skilled in the art to understand or implement the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be practiced in other embodiments without departing from the spirit or scope of the disclosure. Therefore, the present disclosure is not to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

A beamforming method for channel state reference signal CSI-RS, including:

Determine the frequency domain shaping vector based on the frequency domain basis vector;

The channel state reference signal CSI-RS to be transmitted is multiplied by the frequency domain shaping vector to obtain a product result, wherein the product result is used to align the phases in the frequency domain corresponding to the maximum diameter timing advance TA, so as to The maximum diameter TA is compensated;

The product result is multiplied by a spatial domain weight matrix to perform beamforming on the CSI-RS to be transmitted.
The method according to claim 1, wherein determining the frequency domain shaping vector based on the frequency domain basis vector includes:

The signal estimation matrix corresponding to the channel sounding reference signal SRS is summed in the antenna dimension and port dimension respectively to obtain the summation result;

Perform resource block RB merging on the summation results based on frequency domain granularity to obtain the first merging result;

Perform inner product and modulus of the first combined result with each of the frequency domain basis vectors to obtain multiple modulus results;

The frequency domain shaping vector is determined based on the frequency domain basis vector corresponding to the maximum value among the plurality of modular results.
The method according to claim 2, wherein determining the frequency domain shaping vector based on the frequency domain basis vector corresponding to the maximum value in the plurality of modeling results includes:

Perform RB expansion on the frequency domain basis vector corresponding to the maximum value among the plurality of modular results;

The expanded frequency domain basis vector is determined as the frequency domain shaping vector.
The method according to claim 2, wherein before performing inner product and modulo on the first combined result with each of the frequency domain basis vectors to obtain multiple modulo results, the method further includes:

The frequency domain basis vectors equal to the number of the angle division granularities are generated based on the angle division granularity and the frequency domain granularity; wherein the angle division granularity is the number of equal shares of the preset angle.
The method according to claim 2, wherein the signal estimation matrix corresponding to the SRS is summed in the antenna dimension and the port dimension respectively, and the summation result includes:

Merge the signal estimation matrices corresponding to the SRS in the antenna dimension to obtain a second merging result;

The second merging results are merged in the port dimension to obtain a third merging result, where the third merging result is the summation result.
A beamforming device for channel state reference signals, including:

A determination module for determining the frequency domain shaping vector based on the frequency domain basis vector;

The first processing module is used to multiply the channel state reference signal CSI-RS to be transmitted and the frequency domain shaping vector to obtain a product result, wherein the product result is used to align the frequency corresponding to the maximum diameter timing advance TA. The phase on the domain to compensate for the maximum diameter TA;

The second processing module is configured to multiply the product result by the spatial domain weight matrix to perform beamforming on the CSI-RS to be transmitted.
The device according to claim 6, wherein the determining module includes:

The first processing unit is used to perform summation processing on the signal estimation matrices corresponding to the channel sounding reference signal SRS in the antenna dimension and port dimension respectively to obtain the summation result;

A merging unit, configured to merge resource blocks RB on the summation result based on frequency domain granularity to obtain a first merging result;

A second processing unit, configured to perform inner product and modulus of the first combined result with each of the frequency domain basis vectors to obtain multiple modulus results;

A determining unit configured to determine the frequency domain shaping vector based on the frequency domain basis vector corresponding to the maximum value among the plurality of modular results.
The device according to claim 7, wherein the determining unit includes:

An expansion subunit, configured to perform RB expansion on the frequency domain basis vector corresponding to the maximum value in the plurality of modular results;

A determining subunit is used to determine the expanded frequency domain base vector as the frequency domain shaping vector.
An electronic device includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory complete communication with each other through the communication bus;

Memory, used to store computer programs;

The processor is used to implement the method steps described in any one of claims 1-5 when executing a program stored in the memory.
A computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the method steps of any one of claims 1-5 are implemented.