Communication method, communication device, communication system, storage medium and program product

Abstract

A communication method, a communication device, a communication system, a storage medium, and a program product. The communication method comprises: a terminal receiving first information sent by a network device, the first information being used for indicating L wavenumber domain coordinates, and L being a positive integer; and determining a spatial domain orthogonal basis on the basis of the L wavenumber domain coordinates, the spatial domain orthogonal basis comprising L spatial domain basis vectors, and the L spatial domain basis vectors having one-to-one correspondence to the L wavenumber domain coordinates. In embodiments of the present disclosure, a network device configures wavenumber domain coordinates of a channel for a terminal, so that the terminal can calculate a corresponding spatial domain orthogonal basis on the basis of the wavenumber domain coordinates configured by the network device. Thus, the network device does not need to additionally configure some candidate spatial domain orthogonal bases for the terminal, thereby reducing overhead. The saved overhead can be used for quantizing a projection coefficient, and a high-precision quantized coefficient will lead to more accurate CSI.

Description

Communication methods, communication equipment, communication systems, storage media and software products Technical Field

[0001] This disclosure relates to the field of communication technology, and in particular to communication methods, communication devices, communication systems, storage media, and program products. Background Technology

[0002] Multiple-input multiple-output (MIMO) technology can significantly increase data transmission rates without increasing bandwidth, and beamforming gain is proportional to the number of antennas. Therefore, it has always attracted much attention from academia and industry and is one of the core technologies of the physical layer of wireless communication. Summary of the Invention

[0003] This disclosure provides communication methods, communication devices, communication systems, storage media, and program products.

[0004] According to a first aspect of the embodiments of this disclosure, a communication method is provided, executed by a terminal, the method comprising:

[0005] Receive first information sent by the network device, the first information being used to indicate L wavenumber domain coordinates, where L is a positive integer;

[0006] Based on the L wavenumber domain coordinates, a spatial orthogonal basis is determined. The spatial orthogonal basis includes L spatial basis vectors, and the L spatial basis vectors correspond one-to-one with the L wavenumber domain coordinates.

[0007] According to a second aspect of the embodiments of this disclosure, a communication method is provided, performed by a network device, the method comprising:

[0008] Send first information to the terminal. The first information is used to indicate L wavenumber domain coordinates, where L is a positive integer. The L wavenumber domain coordinates are used to determine a spatial orthogonal basis. The spatial orthogonal basis includes L spatial basis vectors, and the L spatial basis vectors correspond one-to-one with the L wavenumber domain coordinates.

[0009] According to a third aspect of the embodiments of this disclosure, a communication method is provided, the method comprising:

[0010] The network device sends first information to the terminal, the first information being used to indicate L wavenumber domain coordinates, where L is a positive integer;

[0011] The terminal determines a spatial orthogonal basis based on the L wavenumber domain coordinates. The spatial orthogonal basis includes L spatial basis vectors, and the L spatial basis vectors correspond one-to-one with the L wavenumber domain coordinates.

[0012] According to a fourth aspect of the present disclosure, a communication device is provided for performing the communication method proposed in the first or second aspect.

[0013] According to a fifth aspect of the present disclosure, a communication system is provided, including a terminal and a network device, wherein the terminal is configured to implement the communication method proposed in the first aspect, and the network device is configured to implement the communication method proposed in the second aspect.

[0014] According to a sixth aspect of the present disclosure, a storage medium is provided that stores instructions which, when executed on a communication device, cause the communication device to perform a communication method as described in the first or second aspect.

[0015] According to a seventh aspect of the present disclosure, a program product is provided, comprising at least one of a program and instructions, wherein when the program or instructions are executed by a communication device, the program or instructions implement the steps of the communication method proposed in the first or second aspect.

[0016] In the above embodiments, the network device configures the wavenumber domain coordinates of the channel for the terminal. The terminal can calculate the corresponding spatial orthogonal basis based on the wavenumber domain coordinates configured by the network device. Therefore, the network device does not need to configure some candidate spatial orthogonal bases for the terminal, thereby reducing overhead. The saved overhead can be used to quantize the projection coefficients. High-precision quantization coefficients will bring more accurate channel state information (CSI). Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the accompanying drawings required for the description of the embodiments are introduced below. The following drawings are only some embodiments of this disclosure and do not impose specific limitations on the protection scope of this disclosure.

[0018] Figure 1 is an exemplary schematic diagram of the architecture of a communication system provided according to an embodiment of the present disclosure.

[0019] Figure 2A is an exemplary interaction diagram of the communication method provided according to an embodiment of the present disclosure.

[0020] Figure 2B is an exemplary interaction diagram of the communication method provided according to an embodiment of the present disclosure.

[0021] Figure 3 is an exemplary interaction diagram of the communication method provided according to an embodiment of the present disclosure.

[0022] Figure 4 is an exemplary interaction diagram of the communication method provided according to an embodiment of the present disclosure.

[0023] Figure 5A is an exemplary schematic diagram of the structure of a terminal provided according to an embodiment of the present disclosure.

[0024] Figure 5B is an exemplary schematic diagram of the structure of a network device provided according to an embodiment of the present disclosure.

[0025] Figure 6A is an exemplary schematic diagram of the structure of a communication device provided according to an embodiment of the present disclosure.

[0026] Figure 6B is an exemplary schematic diagram of the structure of a chip provided according to an embodiment of the present disclosure. Detailed Implementation

[0027] This disclosure provides communication methods, communication devices, communication systems, storage media, and program products.

[0028] In a first aspect, embodiments of this disclosure propose a communication method executed by a terminal, the method comprising: receiving first information sent by a network device, the first information being used to indicate L wavenumber domain coordinates, where L is a positive integer; determining a spatial orthogonal basis based on the L wavenumber domain coordinates, the spatial orthogonal basis comprising L spatial basis vectors, wherein the L spatial basis vectors correspond one-to-one with the L wavenumber domain coordinates.

[0029] In the above embodiments, the network device configures the wavenumber domain coordinates of the channel for the terminal. The terminal can calculate the corresponding spatial orthogonal basis based on the wavenumber domain coordinates configured by the network device. Therefore, the network device does not need to configure some candidate spatial orthogonal bases for the terminal, thereby reducing overhead. The saved overhead can be used to quantize the projection coefficients. High-precision quantization coefficients will bring more accurate CSI.

[0030] In some embodiments, in conjunction with the first aspect, the method further includes: determining a first coefficient matrix based on the spatial orthogonal basis and the first downlink precoding matrix; quantizing the first coefficient matrix to determine a second coefficient matrix; and sending second information to the network device, the second information being used by the network device to determine a third coefficient matrix, the third coefficient matrix being the second coefficient matrix or a sparse matrix corresponding to the second coefficient matrix.

[0031] In the above embodiments, the terminal quantizes the first coefficient matrix and sends the second information to the network device. The network device can reconstruct the second coefficient matrix or its corresponding sparse matrix based on the second information, thus obtaining an accurate CSI. The above embodiments can be used in scenarios where the rank of the downlink channel matrix is ​​greater than 1, corresponding to multiple data layers.

[0032] In conjunction with some embodiments of the first aspect, in some embodiments, the antenna array of the network device is a single-polarization array, and the i-th row of the first coefficient matrix represents the projection coefficients of the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis; or, the antenna array is a dual-polarization array, and the i-th row of the first coefficient matrix represents the projection coefficients of the sub-matrix corresponding to the first polarization direction in the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis, and the L+i-th row represents the projection coefficients of the sub-matrix corresponding to the second polarization direction in the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis; where i is an integer from 1 to L.

[0033] In the above embodiments, the first coefficient matrix represents the projection coefficients of the first downlink precoding matrix onto a spatial orthogonal basis.

[0034] In conjunction with some embodiments of the first aspect, in some embodiments, the second information includes one of the following: the second coefficient matrix; rows in the second coefficient matrix where not all elements are zero; and the row index corresponding to the element with the largest modulus in each column of the second coefficient matrix.

[0035] In the above embodiments, the second information may only report the non-zero rows of the second coefficient matrix, or only report the row index corresponding to the element with the largest modulus in each column of the second coefficient matrix (i.e., r row indices). Compared to reporting all elements in the second coefficient matrix, the feedback overhead of the second information can be reduced. r is the rank of the downlink channel matrix, that is, the number of data layers, and each column in the second coefficient matrix corresponds to one data layer.

[0036] In conjunction with some embodiments of the first aspect, in some embodiments, the antenna array of the network device is a dual-polarization array, and the i-th row of the first coefficient matrix is ​​determined by the projection coefficients of the sub-matrices corresponding to the first polarization direction and the sub-matrices corresponding to the second polarization direction in the first downlink precoding matrix, respectively projected onto the i-th spatial basis vector in the spatial orthogonal basis; where i is an integer from 1 to L.

[0037] In the above embodiments, when the antenna array of the network device is a dual-polarization array, the two polarization directions can correspond to the same coefficient matrix. Therefore, compared with reporting the coefficient matrix corresponding to each polarization direction separately, the feedback overhead of the second information can be reduced.

[0038] In conjunction with some embodiments of the first aspect, in some embodiments, the method further includes: quantizing the first vector to determine the second vector, the first vector containing inter-polarization coefficients of multiple data layers; the second information including the second vector and one of the following: the second coefficient matrix; rows in the second coefficient matrix where not all elements are zero; the row index corresponding to the element with the largest modulus in each column of the second coefficient matrix.

[0039] In the above embodiments, when the antenna array of the network device is a dual-polarization array, and the two polarization directions correspond to the same coefficient matrix, it is only necessary to report the coefficient matrix that corresponds to both polarization directions and the inter-polarization coefficients of each data layer. It is not necessary to report the coefficient matrix corresponding to each polarization direction separately. Therefore, the feedback overhead of the second information can be reduced. In addition, the second information can only report the non-zero rows in the second coefficient matrix, or only report the row index (i.e., r row indices) corresponding to the element with the largest modulus in each column of the second coefficient matrix. Compared with reporting all elements in the second coefficient matrix, the feedback overhead of the second information can be further reduced.

[0040] In conjunction with some embodiments of the first aspect, in some embodiments, the method further includes: measuring a first reference signal transmitted by the network device to determine a channel matrix of a downlink channel; and determining a first downlink precoding matrix based on the channel matrix of the downlink channel.

[0041] In the above embodiments, the terminal calculates the first downlink precoding matrix by measuring the reference signal sent by the network device.

[0042] In some embodiments, in conjunction with the first aspect, the method further includes: determining a first coefficient vector based on the spatial orthogonal basis and the first downlink precoding vector; quantizing the first coefficient vector to determine a second coefficient vector; and sending second information to the network device, the second information being used by the network device to determine a third coefficient vector, the third coefficient vector being the second coefficient vector or a sparse vector corresponding to the second coefficient vector.

[0043] In the above embodiments, the terminal quantizes the first coefficient vector and sends the second information to the network device. The network device can reconstruct the second coefficient vector or its corresponding sparse vector based on the second information, thus obtaining accurate CSI. The above embodiments can be used in scenarios where the rank of the downlink channel matrix is ​​equal to 1, corresponding to a single data layer.

[0044] In conjunction with some embodiments of the first aspect, in some embodiments, the antenna array of the network device is a single-polarization array, and the i-th element in the first coefficient vector represents the projection coefficient of the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis; or, the antenna array is a dual-polarization array, and the i-th element in the first coefficient vector represents the projection coefficient of the sub-vector corresponding to the first polarization direction in the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis, and the L+i-th element represents the projection coefficient of the sub-vector corresponding to the second polarization direction in the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis; where i is an integer from 1 to L.

[0045] In the above embodiments, the first coefficient vector represents the projection coefficients of the first downlink precoding vector onto a spatial orthogonal basis.

[0046] In conjunction with some embodiments of the first aspect, in some embodiments, the second information includes one of the following: the second coefficient vector; non-zero elements in the second coefficient vector; the index corresponding to the element with the largest modulus in the second coefficient vector.

[0047] In the above embodiments, the second information may only report the non-zero elements in the second coefficient vector, or only report the index corresponding to the element with the largest modulus in the second coefficient vector. Compared with reporting all elements in the second coefficient vector, the feedback overhead of the second information can be reduced.

[0048] In conjunction with some embodiments of the first aspect, in some embodiments, the antenna array of the network device is a dual-polarization array, and the i-th element in the first coefficient vector is determined by the projection coefficients of the sub-vectors corresponding to the first polarization direction and the sub-vectors corresponding to the second polarization direction in the first downlink precoding vector, which are respectively projected onto the i-th spatial basis vector in the spatial orthogonal basis; where i is an integer from 1 to L.

[0049] In the above embodiments, when the antenna array of the network device is a dual-polarization array, the two polarization directions can correspond to the same coefficient vector. Therefore, compared with reporting the coefficient vector corresponding to each polarization direction separately, the feedback overhead of the second information can be reduced.

[0050] In conjunction with some embodiments of the first aspect, in some embodiments, the method further includes: quantizing the first vector to determine a second vector, the first vector containing inter-polarization coefficients of a data layer; the second information including the second vector and one of the following: the second coefficient vector; non-zero elements in the second coefficient vector; the index corresponding to the element with the largest modulus in the second coefficient vector.

[0051] In the above embodiments, when the antenna array of the network device is a dual-polarization array, and the two polarization directions correspond to the same coefficient vector, it is only necessary to report the coefficient vector common to both polarization directions and the inter-polarization coefficient of the data layer. It is not necessary to report the coefficient vector corresponding to each polarization direction separately. Therefore, the feedback overhead of the second information can be reduced. Furthermore, the second information can only report the non-zero elements in the second coefficient vector, or only report the index corresponding to the element with the largest magnitude in the second coefficient vector. Compared to reporting all elements in the second coefficient vector, this can further reduce the feedback overhead of the second information.

[0052] In some embodiments, in conjunction with the first aspect, the method further includes: measuring a first reference signal transmitted by the network device to determine a channel matrix of a downlink channel; and determining a first downlink precoding vector based on the channel matrix of the downlink channel.

[0053] In the above embodiments, the terminal calculates the first downlink precoding vector by measuring the reference signal sent by the network device.

[0054] In conjunction with some embodiments of the first aspect, in some embodiments, the L wavenumber domain coordinates are the L wavenumber domain coordinates with the highest power in the wavenumber domain power distribution of the downlink channel; or, the L wavenumber domain coordinates are the wavenumber domain coordinates with power greater than a threshold in the wavenumber domain power distribution of the downlink channel.

[0055] In the above embodiments, since the network device only needs to configure the coordinates of the high-power partial paths (or clusters) in the wavenumber domain representation of the downlink channel, the configuration signaling overhead of the wavenumber domain coordinates can be reduced. Furthermore, the terminal only needs to calculate the spatial basis vectors corresponding to the coordinates of the high-power partial paths (or clusters), thus reducing computation and improving system efficiency.

[0056] In conjunction with some embodiments of the first aspect, in some embodiments, the method further includes: sending a second reference signal to the network device, the second reference signal being used by the network device to determine the wavenumber domain power distribution of the downlink channel.

[0057] In the above embodiments, by sending a reference signal through the terminal, the network device can obtain the uplink channel by measuring the reference signal sent by the terminal, and derive the downlink channel by utilizing the reciprocity of the uplink and downlink channels, thereby obtaining the power distribution of the downlink channel in the wavenumber domain.

[0058] In conjunction with some embodiments of the first aspect, in some embodiments, each of the wavenumber domain coordinates is normalized to the wavenumber. λ is the wavelength; or, each of the wavenumber domain coordinates is normalized to the wavenumber domain quantization interval.

[0059] In the above embodiment, the L wavenumber domain coordinates can be normalized to the wavenumber. Alternatively, wavenumber domain quantization intervals can reduce the signaling overhead of wavenumber domain coordinate configuration. On the other hand, they make the configured wavenumber domain coordinates independent of the carrier frequency, enabling wireless communication systems operating on different carrier frequencies to share a common implementation (such as in protocol stack software development). This consistency can reduce costs.

[0060] In conjunction with some embodiments of the first aspect, in some embodiments, the antenna array of the network device is a one-dimensional array, and the spatial orthogonal basis is represented as... Where N is the number of antennas or antenna ports in the antenna array in one polarization direction. Let k be the i-th spatial basis vector in the spatial orthogonal basis. i This represents the i-th wavenumber domain coordinate among the L wavenumber domain coordinates, where r = [r1 r2 … r N ] T r n This represents the coordinates of the nth antenna or antenna port in the antenna array, where n = 1, 2, ..., N.

[0061] In the above embodiments, a method for implementing spatial orthogonal basis when the antenna array on the network device side is a one-dimensional array is proposed. In this method, one spatial basis vector in the spatial orthogonal basis corresponds to one wavenumber domain coordinate in L wavenumber domain coordinates. Therefore, the terminal can calculate the corresponding spatial orthogonal basis according to the wavenumber domain coordinates configured by the network device, without the need for the network device to configure some candidate spatial orthogonal basis.

[0062] In conjunction with some embodiments of the first aspect, in some embodiments, the antenna array of the network device is a two-dimensional array, and the spatial orthogonal basis is represented as... Wherein, N1 is the number of antennas or antenna ports in the horizontal direction of the antenna array in one polarization direction, and N2 is the number of antennas or antenna ports in the vertical direction of the antenna array in one polarization direction. Let be the i-th spatial basis vector in the spatial orthogonal basis, (k h,i ,k v,i () represents the i-th wavenumber domain coordinate among the L wavenumber domain coordinates. The coordinates of the antenna or antenna port in the n2th row and n1th column of the antenna array are represented, where n1 = 1, 2, ..., N1 and n2 = 1, 2, ..., N2.

[0063] In the above embodiments, a method for implementing spatial orthogonal bases when the antenna array on the network device side is a two-dimensional array is proposed. In this method, one spatial basis vector in the spatial orthogonal base corresponds to one wavenumber domain coordinate in L wavenumber domain coordinates. Therefore, the terminal can calculate the corresponding spatial orthogonal base according to the wavenumber domain coordinates configured by the network device, without the need for the network device to configure some candidate spatial orthogonal bases.

[0064] Secondly, embodiments of this disclosure provide a communication method executed by a network device, the method comprising:

[0065] Send first information to the terminal. The first information is used to indicate L wavenumber domain coordinates, where L is a positive integer. The L wavenumber domain coordinates are used to determine a spatial orthogonal basis. The spatial orthogonal basis includes L spatial basis vectors, and the L spatial basis vectors correspond one-to-one with the L wavenumber domain coordinates.

[0066] In the above embodiments, the wavenumber domain coordinates of the channel are configured for the terminal by the network device. The terminal can calculate the corresponding spatial orthogonal basis according to the wavenumber domain coordinates configured by the network device. Therefore, the network device does not need to configure some candidate spatial orthogonal bases for the terminal, thereby reducing overhead. The saved overhead can be used for the terminal to quantize the projection coefficients. High-precision quantization coefficients will bring more accurate CSI.

[0067] In conjunction with some embodiments of the second aspect, in some embodiments, the method further includes: receiving second information sent by the terminal; determining a third coefficient matrix based on the second information, the third coefficient matrix being a second coefficient matrix or a sparse matrix corresponding to the second coefficient matrix, wherein the second coefficient matrix is ​​a matrix obtained by quantizing a first coefficient matrix, and the first coefficient matrix is ​​determined by the terminal based on the spatial orthogonal basis and a first downlink precoding matrix; and determining a second downlink precoding matrix based on the spatial orthogonal basis and the third coefficient matrix.

[0068] In conjunction with some embodiments of the second aspect, in some embodiments, the antenna array of the network device is a single-polarization array, and the i-th row of the first coefficient matrix represents the projection coefficients of the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis; or, the antenna array is a dual-polarization array, and the i-th row of the first coefficient matrix represents the projection coefficients of the sub-matrix corresponding to the first polarization direction in the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis, and the L+i-th row represents the projection coefficients of the sub-matrix corresponding to the second polarization direction in the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis; where i is an integer from 1 to L.

[0069] In conjunction with some embodiments of the second aspect, in some embodiments, the second information includes one of the following: the second coefficient matrix; rows in the second coefficient matrix where not all elements are zero; and the row index corresponding to the element with the largest modulus in each column of the second coefficient matrix.

[0070] In conjunction with some embodiments of the second aspect, in some embodiments, the antenna array of the network device is a dual-polarization array, and the i-th row of the first coefficient matrix is ​​determined by the projection coefficients of the sub-matrix corresponding to the first polarization direction and the sub-matrix corresponding to the second polarization direction in the first downlink precoding matrix, respectively projected onto the i-th spatial basis vector in the spatial orthogonal basis; where i is an integer from 1 to L.

[0071] In conjunction with some embodiments of the second aspect, in some embodiments, the second information includes a second vector, which is a vector obtained by quantizing a first vector, the first vector including polarization coefficients of multiple data layers; and the second information further includes one of the following: a second coefficient matrix; rows in the second coefficient matrix where not all elements are zero; and the row index corresponding to the element with the largest modulus in each column of the second coefficient matrix.

[0072] In conjunction with some embodiments of the second aspect, in some embodiments, the second downlink precoding matrix is ​​represented as I2 is a 2×2 identity matrix, B is the spatial orthogonal basis, r is the rank, and Q(c p ) is the second vector, The third coefficient matrix, ⊙ represents the Kronecker product operation, and ⊙ represents the Khatri-Rao product operation.

[0073] In the above embodiments, a method for implementing the second downlink precoding matrix is ​​proposed when the antenna array of the network device is a dual-polarization array and the two polarization directions correspond to the same coefficient matrix.

[0074] In conjunction with some embodiments of the second aspect, in some embodiments, when the second information contains the row index corresponding to the element with the largest modulus value in each column of the second coefficient matrix, the third coefficient matrix is ​​a sparse matrix corresponding to the second coefficient matrix, wherein the element corresponding to the row index position in each column of the sparse matrix is ​​1, and all other elements are 0.

[0075] In the above embodiment, if the second information contains the row index (i.e., r row indices) corresponding to the element with the largest modulus in each column of the second coefficient matrix, the network device can determine the sparse matrix corresponding to the second coefficient matrix based on the r row indices. Since the second information only contains r row indices for the second coefficient matrix, the feedback overhead of the second information can be reduced.

[0076] In conjunction with some embodiments of the second aspect, in some embodiments, the method further includes: sending a first reference signal to the terminal, the first reference signal being used by the terminal to determine the first downlink precoding matrix.

[0077] In conjunction with some embodiments of the second aspect, in some embodiments, the method further includes: receiving second information sent by the terminal; determining a third coefficient vector based on the second information, the third coefficient vector being a second coefficient vector or a sparse vector corresponding to the second coefficient vector, wherein the second coefficient vector is a vector obtained by quantizing a first coefficient vector, and the first coefficient vector is determined by the terminal based on the spatial orthogonal basis and a first downlink precoding vector; and determining a second downlink precoding vector based on the spatial orthogonal basis and the third coefficient vector.

[0078] In conjunction with some embodiments of the second aspect, in some embodiments, the antenna array of the network device is a single-polarization array, and the i-th element in the first coefficient vector represents the projection coefficient of the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis; or, the antenna array is a dual-polarization array, and the i-th element in the first coefficient vector represents the projection coefficient of the sub-vector corresponding to the first polarization direction in the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis, and the L+i-th element represents the projection coefficient of the sub-vector corresponding to the second polarization direction in the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis; where i is an integer from 1 to L.

[0079] In conjunction with some embodiments of the second aspect, in some embodiments, the second information includes one of the following: the second coefficient vector; non-zero elements in the second coefficient vector; the index corresponding to the element with the largest modulus in the second coefficient vector.

[0080] In conjunction with some embodiments of the second aspect, in some embodiments, the antenna array of the network device is a dual-polarization array, and the i-th element in the first coefficient vector is determined by the projection coefficients of the sub-vectors corresponding to the first polarization direction and the sub-vectors corresponding to the second polarization direction in the first downlink precoding vector, which are respectively projected onto the i-th spatial basis vector in the spatial orthogonal basis; where i is an integer from 1 to L.

[0081] In conjunction with some embodiments of the second aspect, in some embodiments, the second information includes a second vector, which is a vector obtained by quantizing the first vector, the first vector including inter-polarization coefficients of a data layer; and the second information further includes one of the following: the second coefficient vector; non-zero elements in the second coefficient vector; the index corresponding to the element with the largest modulus in the second coefficient vector.

[0082] In conjunction with some embodiments of the second aspect, in some embodiments, the second downlink precoding vector is represented as I2 is a 2×2 identity matrix, B is the spatial orthogonal basis, and Q(c p ) is the second vector, For the third coefficient vector, ⊙ represents the Kronecker product operation, and ⊙ represents the Khatri-Rao product operation.

[0083] In the above embodiments, a method for implementing the second downlink precoding vector is proposed when the antenna array of the network device is a dual-polarization array and the two polarization directions correspond to the same coefficient vector.

[0084] In conjunction with some embodiments of the second aspect, in some embodiments, when the second information includes the index corresponding to the element with the largest modulus in the second coefficient vector, the third coefficient vector is a sparse vector corresponding to the second coefficient vector, wherein the element corresponding to the index position in the sparse vector is 1, and all other elements are 0.

[0085] In the above embodiments, if the second information contains the index corresponding to the element with the largest modulus in the second coefficient vector, the network device can determine the sparse vector corresponding to the second coefficient vector based on the index. Since the second information contains only one index for the second coefficient vector, the feedback overhead of the second information can be reduced.

[0086] In conjunction with some embodiments of the second aspect, in some embodiments, the method further includes: sending a first reference signal to the terminal, the first reference signal being used by the terminal to determine the first downlink precoding vector.

[0087] In conjunction with some embodiments of the second aspect, in some embodiments, the L wavenumber domain coordinates are the L wavenumber domain coordinates with the highest power in the wavenumber domain power distribution of the downlink channel; or, the L wavenumber domain coordinates are the wavenumber domain coordinates with power greater than a threshold in the wavenumber domain power distribution of the downlink channel.

[0088] In some embodiments, in conjunction with the second aspect, the method further includes: measuring a second reference signal transmitted by the terminal to determine the channel matrix of the uplink channel; and determining the wavenumber domain power distribution of the downlink channel based on the channel matrix of the uplink channel.

[0089] In conjunction with some embodiments of the second aspect, in some embodiments, each of the wavenumber domain coordinates is normalized to the wavenumber. λ is the wavelength; or, each of the wavenumber domain coordinates is normalized to the wavenumber domain quantization interval.

[0090] In conjunction with some embodiments of the second aspect, in some embodiments, the antenna array of the network device is a one-dimensional array, and the spatial orthogonal basis is represented as... Where N is the number of antennas or antenna ports in the antenna array in one polarization direction. Let k be the i-th spatial basis vector in the spatial orthogonal basis. i This represents the i-th wavenumber domain coordinate among the L wavenumber domain coordinates, where r = [r1 r2 … r N ] T r n The coordinates of the nth antenna or antenna port in the antenna array are represented, where n = 1, 2, ..., N.

[0091] In conjunction with some embodiments of the second aspect, in some embodiments, the antenna array of the network device is a two-dimensional array, and the spatial orthogonal basis is represented as... Wherein, N1 is the number of antennas or antenna ports in the horizontal direction of the antenna array in one polarization direction, and N2 is the number of antennas or antenna ports in the vertical direction of the antenna array in one polarization direction. Let be the i-th spatial basis vector in the spatial orthogonal basis, (k h，i k v，i () represents the i-th wavenumber domain coordinate among the L wavenumber domain coordinates. The coordinates of the antenna or antenna port in the n2th row and n1th column of the antenna array are represented, where n1 = 1, 2, ..., N1 and n2 = 1, 2, ..., N2.

[0092] Thirdly, this disclosure provides a communication method, the method comprising: a network device sending first information to a terminal, the first information indicating L wavenumber domain coordinates, where L is a positive integer; the terminal determining a spatial orthogonal basis based on the L wavenumber domain coordinates, the spatial orthogonal basis comprising L spatial basis vectors, the L spatial basis vectors corresponding one-to-one with the L wavenumber domain coordinates.

[0093] Fourthly, embodiments of this disclosure provide a communication device for performing the method described in an optional implementation of the first or second aspect.

[0094] Fifthly, embodiments of this disclosure provide a communication system including a terminal and a network device, wherein the terminal is configured to implement the method described in the optional implementation of the first aspect, and the network device is configured to implement the method described in the optional implementation of the second aspect.

[0095] In a sixth aspect, embodiments of this disclosure provide a storage medium storing instructions that, when executed on a communication device, cause the communication device to perform the method as described in an optional implementation of the first or second aspect.

[0096] In a seventh aspect, embodiments of this disclosure provide a program product comprising at least one of a program and instructions, wherein the program and instructions, when executed by a communication device, implement the steps of the method described in the optional implementation of the first or second aspect.

[0097] It is understood that the aforementioned communication equipment, communication system, storage medium, program product, etc., are all used to execute the methods proposed in the embodiments of this disclosure. Therefore, the beneficial effects they can achieve can be referred to the beneficial effects in the corresponding methods, and will not be repeated here.

[0098] This disclosure is not exhaustive, but merely illustrative of some embodiments, and is not intended to limit the scope of protection of this disclosure. Unless otherwise specified, each step in a particular embodiment can be implemented as an independent embodiment, and the steps can be arbitrarily combined. For example, a solution after removing some steps in a particular embodiment can also be implemented as an independent embodiment, and the order of the steps in a particular embodiment can be arbitrarily interchanged. Furthermore, the optional implementation methods in a particular embodiment can be arbitrarily combined; moreover, the embodiments can be arbitrarily combined, for example, some or all steps of different embodiments can be arbitrarily combined, and a particular embodiment can be arbitrarily combined with the optional implementation methods of other embodiments. In all embodiments of this disclosure, unless otherwise specified or logically conflicting, the terminology and / or descriptions between the embodiments are consistent and can be mutually referenced. Technical features in different embodiments can be combined to form new embodiments based on their inherent logical relationships.

[0099] The terminology used in the embodiments of this disclosure is for the purpose of describing particular embodiments only and is not intended to limit the scope of this disclosure.

[0100] In this embodiment of the disclosure, unless otherwise stated, elements expressed in the singular form, such as "a," "an," "the," "the," "the," "the," "the," "the," "this," etc., can mean "one and only one," or "one or more," "at least one," etc. For example, when using articles such as "a," "an," "the," etc. in translation, the noun following the article can be understood as either a singular expression or a plural expression.

[0101] In the embodiments disclosed herein, "multiple" refers to two or more.

[0102] In some embodiments, the terms “at least one of A or B, at least one of A and B”, “one or more”, “a plurality of”, “multiple”, etc., may be used interchangeably.

[0103] In some embodiments, the notation "at least one of A and B", "A and / or B", "A in one case, B in another", "in response to one case A, in response to another case B", etc., may include the following technical solutions depending on the situation: in some embodiments, A (execute A regardless of whether there is a branch B); in some embodiments, B (execute B regardless of whether there is a branch A); in some embodiments, execution is selected from A and B (A and B are selectively executed); in some embodiments, both A and B are executed. The same applies when there are more branches such as A, B, C, etc.

[0104] In some embodiments, the notation "A or B" may include the following technical solutions, depending on the situation: in some embodiments, A (execute A regardless of whether a branch B exists); in some embodiments, B (execute B regardless of whether a branch A exists); in some embodiments, execution is selected from A and B (A and B are selectively executed). The same applies when there are more branches such as A, B, and C.

[0105] The prefixes "first," "second," etc., used in the embodiments of this disclosure are merely for distinguishing different descriptive objects and do not impose restrictions on the position, order, priority, quantity, or content of the descriptive objects. The description of the descriptive objects is found in the claims or the context of the embodiments, and the use of prefixes should not constitute unnecessary restrictions. For example, if the descriptive object is a "field," the ordinal numbers preceding "field" in "first field" and "second field" do not restrict the position or order of the "fields." "First" and "second" do not restrict whether the "fields" they modify are in the same message, nor do they restrict the order of "first field" and "second field." Similarly, if the descriptive object is a "level," the ordinal numbers preceding "level" in "first level" and "second level" do not restrict the priority between "levels." Furthermore, the number of descriptive objects is not limited by ordinal numbers and can be one or more. For example, in "first device," the number of "devices" can be one or more. Furthermore, the objects modified by different prefixes can be the same or different. For example, if the object being described is "device", then "first device" and "second device" can be the same device or different devices, and their types can be the same or different. Similarly, if the object being described is "information", then "first information" and "second information" can be the same information or different information, and their content can be the same or different.

[0106] In some embodiments, “including A,” “containing A,” “for indicating A,” and “carrying A” can be interpreted as directly carrying A or indirectly indicating A.

[0107] In some embodiments, terms such as "time / frequency" and "time-frequency domain" refer to the time domain and / or frequency domain.

[0108] In some embodiments, terms such as “in response to…”, “in response to determining…”, “in the case of…”, “when…”, “when…”, “if…”, etc. can be used interchangeably. These descriptions all refer to the device making a corresponding action under certain objective circumstances. They do not necessarily limit the time, nor do they require the device to make a judgment action when implementing it, nor do they mean that there must be other limitations.

[0109] In some embodiments, the terms “greater than,” “greater than or equal to,” “not less than,” “more than,” “more than or equal to,” “not less than,” “higher than,” “higher than or equal to,” “not lower than,” and “above” can be used interchangeably, as can the terms “less than,” “less than or equal to,” “not greater than,” “less than,” “less than or equal to,” “not more than,” “lower than,” “lower than or equal to,” “not higher than,” and “below”.

[0110] In some embodiments, devices, etc., may be interpreted as physical or virtual, and their names are not limited to those described in the embodiments. Terms such as “device,” “equipment,” “circuit,” “network element,” “network function,” “network device,” “function,” “node,” “unit,” “section,” “system,” “network,” “chip,” “chip system,” “entity,” and “subject” are interchangeable.

[0111] In some embodiments, "network" can be interpreted as devices included in a network (e.g., access network devices, core network devices, etc.).

[0112] In some embodiments, the terms "access network device (AN device)," "radio access network device (RAN device)," "base station (BS)," "radio base station," "fixed station," "node," "access point," "transmission point (TP)," "reception point (RP)," "transmission / reception point (TRP)," "panel," "antenna panel," "antenna array," "cell," "macro cell," "small cell," "femto cell," "pico cell," "sector," "cell group," "serving cell," "carrier," "component carrier," and "bandwidth part (BWP)" can be used interchangeably.

[0113] In some embodiments, the terms "terminal", "terminal device", "user equipment (UE)", "user terminal", "mobile station (MS)", "mobile terminal (MT)", "subscriber station", "mobile unit", "subscriber unit", "wireless unit", "remote unit", "mobile device", "wireless device", "wireless communication device", "remote device", "mobile subscriber station", "access terminal", "mobile terminal", "wireless terminal", "remote terminal", "handset", "user agent", "mobile client", and "client" can be used interchangeably.

[0114] In some embodiments, access network devices, core network devices, or network devices can be replaced by terminals. For example, embodiments of this disclosure can also be applied to structures where communication between access network devices, core network devices, or network devices and terminals is replaced by communication between multiple terminals (e.g., device-to-device (D2D), vehicle-to-everything (V2X), etc.). In this case, the structure can also be configured such that the terminal has all or part of the functions of the access network device. Furthermore, terms such as "uplink" and "downlink" can be replaced with terms corresponding to communication between terminals (e.g., "sidelink"). For example, uplink channel, downlink channel, etc., can be replaced with sidelink channel, and uplink link, downlink, etc., can be replaced with sidelink link.

[0115] In some embodiments, the terminal may be replaced by an access network device, a core network device, or a network device. In this case, the access network device, core network device, or network device may also be configured to have all or some of the functions of the terminal.

[0116] In some embodiments, the acquisition of data, information, etc., may comply with the laws and regulations of the country where the location is situated.

[0117] In some embodiments, data, information, etc., may be obtained with the user's consent.

[0118] Furthermore, each element, each row, or each column in the table of this disclosure can be implemented as an independent embodiment, and any combination of any element, any row, or any column can also be implemented as an independent embodiment.

[0119] Figure 1 is a schematic diagram of the architecture of a communication system according to an embodiment of the present disclosure. As shown in Figure 1, the communication system 100 includes a terminal 101 and a network device 102.

[0120] In some embodiments, terminal 101 includes, but is not limited to, at least one of the following: mobile phone, wearable device, Internet of Things device, car with communication function, smart car, smart door lock, tablet computer, computer with wireless transceiver function, virtual reality (VR) terminal device, augmented reality (AR) terminal device, wireless terminal device in industrial control, wireless terminal device in self-driving, wireless terminal device in remote medical surgery, wireless terminal device in smart grid, wireless terminal device in transportation safety, wireless terminal device in smart city, and wireless terminal device in smart home.

[0121] In some embodiments, network device 102 may include at least one of access network device and core network device. In some embodiments, access network device is, for example, a node or device that connects a terminal to a wireless network. Access network device may include, but is not limited to, at least one of the following in a 5G communication system: evolved Node B (eNB), next-generation evolved Node B (ng-eNB), next-generation Node B (gNB), node B (NB), home node B (HNB), home evolved node B (HeNB), radio backhaul device, radio network controller (RNC), base station controller (BSC), base transceiver station (BTS), base band unit (BBU), mobile switching center, base station in a 6G communication system, open RAN, cloud RAN, base station in other communication systems, and access node in a Wi-Fi system.

[0122] In some embodiments, a core network device may be a single device comprising one or more network elements, or it may be multiple devices or a group of devices, each comprising all or part of the aforementioned one or more network elements. Network elements may be virtual or physical. The core network may include, for example, at least one of an Evolved Packet Core (EPC), a 5G Core Network (5GCN), or a Next Generation Core (NGC).

[0123] In some embodiments, the technical solutions of this disclosure can be applied to the Open RAN architecture. In this case, the interfaces between or within access network devices involved in the embodiments of this disclosure can be transformed into internal interfaces of Open RAN. The processes and information interactions between these internal interfaces can be implemented by software or programs.

[0124] In some embodiments, the access network device may be composed of a central unit (CU) and a distributed unit (DU). The CU may also be called a control unit. The CU-DU structure can separate the protocol layer of the access network device. Some of the protocol layer functions are centrally controlled by the CU, while the remaining part or all of the protocol layer functions are distributed in the DU and centrally controlled by the CU. However, this is not the only possibility.

[0125] It is understood that the system described in this disclosure is for the purpose of more clearly illustrating the technical solutions of this disclosure, and does not constitute a limitation on the technical solutions proposed in this disclosure. As those skilled in the art will know, with the evolution of system architecture and the emergence of new business scenarios, the technical solutions proposed in this disclosure are also applicable to similar technical problems.

[0126] The following embodiments of this disclosure can be applied to the communication system 100 shown in FIG1, or to some of the main bodies, but are not limited thereto. The main bodies shown in FIG1 are illustrative. The communication system may include all or some of the main bodies in FIG1, or may include other main bodies outside of FIG1. ​​The number and form of each main body are arbitrary. Each main body may be physical or virtual. The connection relationship between the main bodies is illustrative. The main bodies may not be connected or may be connected. The connection can be in any way, it can be a direct connection or an indirect connection, it can be a wired connection or a wireless connection.

[0127] The embodiments disclosed herein can be applied to Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), 5G new radio (NR), Future Radio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR), New radio access (NX), Future generation radio access (FX), Global System for Mobile communications (GSM), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), and IEEE 802.20, Ultra-Wideband (UWB), Bluetooth (a registered trademark), Public Land Mobile Network (PLMN) networks, Device-to-Device (D2D) systems, Machine-to-Machine (M2M) systems, Internet of Things (IoT) systems, Vehicle-to-Everything (V2X) systems, systems utilizing other communication methods, and next-generation systems built upon them, etc. Furthermore, multiple systems can be combined (e.g., a combination of LTE or LTE-A with 5G).

[0128] Multiple-input multiple-output (MIMO) technology can significantly improve data transmission rates without increasing bandwidth. Moreover, beamforming gain is proportional to the number of antennas, so it has always attracted much attention from academia and industry and is one of the core technologies of the physical layer of wireless communication.

[0129] Current low- and mid-frequency spectrum resources are already overcrowded. To meet the ever-increasing demand for data rates, academia and industry have begun exploring higher-frequency spectrum resources, such as millimeter-wave and terahertz bands. High-frequency transmission suffers from greater transmission attenuation, especially due to severe absorption by water molecules and oxygen in the air, resulting in very limited transmission distance and coverage. However, higher frequencies mean shorter wavelengths, allowing for the deployment of more antennas within the same aperture size compared to low- and mid-frequency spectrum. Therefore, multi-antenna technology can effectively compensate for high-frequency transmission losses, thereby extending coverage and transmission distance.

[0130] In summary, MIMO technology is one of the most important physical layer transmission technologies in recent decades. Examples include MIMO in 4G LTE systems and massive MIMO in 5G NR systems. In the preliminary research for 6G wireless communication technologies, MIMO technology has once again gained favor not only from academia but also from widespread support from industry.

[0131] MIMO technology not only improves communication reliability but also significantly enhances the spectral efficiency and channel capacity of communication channels. However, the superior performance of MIMO heavily relies on accurate channel state information (CSI), especially spatial CSI. In wireless cellular systems, the gNB typically acquires CSI using two methods: The first method involves the gNB measuring the sounding reference signal (SRS) transmitted by the UE, utilizing channel reciprocity to obtain the downlink channel CSI and determine the downlink precoding vector (or matrix). This method is commonly used in situations with good uplink and downlink channel reciprocity, such as in time division duplex (TDD) systems. The second method involves the gNB transmitting a dedicated reference signal for acquiring CSI, namely the channel state information reference signal (CSI-RS). The UE measures the CSI-RS and calculates the precoding vector (or matrix) for downlink transmission based on it, then reports the downlink precoding vector (or matrix) to the gNB via a codebook. Currently, codebooks in 5G NR systems include two types: Type 1 and Type 2. Type 1 is a predefined set of precoding vectors (or matrices). The UE finds the precoding vector (or matrix) that best matches the channel within this set and reports its number to the gNB. Type 2 requires projecting the precoding vector (or matrix) to be fed back onto some incomplete candidate spatial basis vectors, and then reporting the numbers of the candidate spatial basis vectors and the quantized projection coefficients to the gNB. Type 1 codebooks have lower overhead than Type 2 codebooks; however, Type 2 codebooks can provide the gNB with more accurate spatial CSI. Therefore, the performance of Type 2 codebooks is far superior to that of Type 1 codebooks, especially in multi-user (MU) MIMO scenarios.

[0132] On the other hand, the wavenumber domain representation of MIMO channels provides a completely new perspective for understanding MIMO channels. In related technologies, based on the Helmholtz equations and Weyl expansion, the channel from the transmitter (located at spatial point s) to the receiver (located at spatial point r) can be represented as:

[0133] in,

[0134] The wavenumber vector corresponding to the source or transmitter.

[0135] This is the wavenumber vector corresponding to the receiving end.

[0136] H(k x ,k y ,κ x ,κ y () represents the wavenumber domain response of the channel;

[0137] This refers to the source response or the wavenumber domain response of the transmitting array.

[0138] This refers to the receive response or the wavenumber domain response of the receiver array.

[0139] Let λ be the wave number and λ be the wavelength.

[0140] The wavenumber domain is a domain used in signal processing, such as converting a channel from the spatial domain to the wavenumber domain. In communication systems, the wavenumber domain representation of a channel can be used to analyze changes in signal propagation in space, such as multipath propagation effects. By converting the channel from the spatial domain to the wavenumber domain, the amplitude or power variations of the signal on different paths (or clusters) can be observed more intuitively, thus providing a better understanding of the channel's impact on signal transmission. For example, in some wireless communication scenarios, the wavenumber domain representation of the channel (such as wavenumber power distribution) can help study the propagation characteristics of signals on different paths (or clusters).

[0141] It should be noted that in some related academic research, antenna arrays are usually studied and discussed in the xoy plane, so x generally represents the horizontal direction and y generally represents the vertical direction. However, in practical applications, especially in 3GPP technical reports, antenna arrays are often studied and discussed in the yoz plane, where y represents the horizontal direction and z represents the vertical direction. For ease of understanding, in the embodiments of this disclosure, the subscript h represents the horizontal direction and the subscript v represents the vertical direction.

[0142] Figure 2A is an interactive schematic diagram of a communication method according to an embodiment of the present disclosure. As shown in Figure 2A, the embodiments of the present disclosure relate to a communication method, which includes:

[0143] Step S2101: The network device sends the first information to the terminal.

[0144] In some embodiments, the first information is used to indicate L wavenumber domain coordinates.

[0145] In some embodiments, the first information is used by the network device to configure a wavenumber domain coordinate list for the terminal. The wavenumber domain coordinate list includes one or more wavenumber domain coordinates, the number of which is denoted as L, where L is a positive integer.

[0146] In some embodiments, the name of the first information is not limited, and it may be, for example, "wavenumber domain coordinate list", "wavenumber domain coordinate information", "configuration information", "coordinate configuration information", etc.

[0147] The wavenumber domain coordinate list corresponds to all paths (or clusters) or the most powerful paths (or clusters) in the wavenumber domain representation (such as wavenumber domain power distribution) of the downlink channel between network devices and terminals. The wavenumber domain representation of the downlink channel describes its characteristics in the wavenumber domain, such as power distribution. The wavenumber domain power distribution of the downlink channel describes the power corresponding to different coordinates in the wavenumber domain; the power corresponding to a coordinate in the wavenumber domain can represent the power of a path (or cluster) of the downlink channel in that direction.

[0148] In some embodiments, the list of wavenumber domain coordinates includes the coordinates of all paths (or clusters) in the wavenumber domain power distribution of the downlink channel.

[0149] In some embodiments, the wavenumber domain coordinate list includes the coordinates of the most powerful partial paths (or clusters) in the wavenumber domain power distribution of the downlink channel. For example, the L wavenumber domain coordinates are the L most powerful wavenumber domain coordinates in the wavenumber domain power distribution of the downlink channel, or the L wavenumber domain coordinates are the wavenumber domain coordinates of the wavenumber domain power distribution of the downlink channel whose power is greater than a threshold. Since the network device only needs to configure the coordinates of the most powerful partial paths (or clusters) in the wavenumber domain representation of the downlink channel, the configuration overhead of the wavenumber domain coordinates can be reduced. Furthermore, the terminal only needs to calculate the spatial basis vectors corresponding to the coordinates of the most powerful partial paths (or clusters), thus reducing computation and improving system efficiency.

[0150] In some embodiments, the network device can utilize the reciprocity of the channel to obtain the wavenumber domain power distribution of the downlink channel. For example, a terminal sends a second reference signal (such as a sounding reference signal (SRS)) to the network device. The network device measures the second reference signal sent by the terminal, determines the channel matrix of the uplink channel, and determines the wavenumber domain power distribution of the downlink channel based on the channel matrix of the uplink channel. Therefore, the network device obtains the uplink channel by measuring the reference signal sent by the terminal and derives the downlink channel using the reciprocity of the uplink and downlink channels, thereby obtaining the power distribution of the downlink channel in the wavenumber domain. After obtaining the power distribution of the downlink channel in the wavenumber domain, the network device identifies the wavenumber domain coordinates with higher power, such as the L wavenumber domain coordinates with the highest power, or the wavenumber domain coordinates with power greater than a threshold, and arranges them in a list. Optionally, the L wavenumber domain coordinates are arranged in descending order of the power corresponding to each wavenumber domain coordinate.

[0151] In some embodiments, the network device may also obtain the wavenumber domain power distribution of the downlink channel in other ways, such as by calculating the wavenumber domain power distribution of the downlink channel based on parameters reported by the terminal via a channel state information reference signal (CSI-RS). This disclosure does not limit the method by which the network device obtains the wavenumber domain power distribution of the downlink channel.

[0152] In some embodiments, the wavenumber domain is quantized into multiple wavenumber domain cells, each corresponding to a quantization coordinate. Optionally, if the antenna array of the network device is a one-dimensional array, then the wavenumber domain is distributed within a one-dimensional interval [-κ0, κ0], the wavenumber domain cells are one-dimensional cells, and the wavenumber domain quantization interval is denoted as Δ, which is also the size of the wavenumber domain cell. Optionally, if the antenna array of the network device is a two-dimensional array, then the wavenumber domain is distributed within a circle of radius k0, the wavenumber domain cells are two-dimensional cells, and the wavenumber domain quantization interval is denoted as (Δ... h ,Δ v ), Δ h Δ represents the quantization interval in the horizontal direction of the wavenumber domain, i.e., the size of a wavenumber domain cell in the horizontal direction. v This represents the quantization interval of the wavenumber domain in the vertical direction, which is also the size of the wavenumber domain cell in the vertical direction.

[0153] In some embodiments, if the antenna array of the network device is a one-dimensional array, then each element (wavenumber domain coordinate) in the list of wavenumber domain coordinates is a scalar.

[0154] Optionally, the list of wavenumber domain coordinates can be represented as Where -k0≤ki ≤k0, i=1,2,…,L. k i This represents the coordinates of the i-th wavenumber domain.

[0155] Optionally, each element (wavenumber domain coordinate) in the list of wavenumber domain coordinates can be normalized to the wavenumber. A list of wavenumber domain coordinates can be represented as in, i = 1, 2, ..., L.

[0156] Optionally, each element (wavenumber domain coordinate) in the list of wavenumber domain coordinates can be normalized to the wavenumber domain quantization interval Δ, and the list of wavenumber domain coordinates can be represented as follows: in, or

[0157] Optionally, the value of the wavenumber domain quantization interval Δ can be predefined by the protocol or explicitly configured to the terminal by the network device.

[0158] Optionally, Where A is the aperture of the antenna array (one-dimensional array) of the network device. In this case, for Integers between, that is

[0159] Optionally, wavenumber domain quantization interval Alternatively, the aperture A of the one-dimensional array can be explicitly configured by the network device to the terminal. This can be understood as the quantization interval. The wavenumber domain corresponds to the Nyquist sampling rate. Therefore, quantizing the wavenumber domain at this quantization interval can achieve a balance between performance (accuracy) and signaling overhead.

[0160] In some embodiments, if the antenna array of the network device is a two-dimensional array, then each element (wavenumber domain coordinate) in the wavenumber domain coordinate list is a tuple, i.e., a two-dimensional coordinate.

[0161] Optionally, the list of wavenumber domain coordinates can be represented as in, i = 1, 2, ..., L. (κ) h，i κ v，i ) represents the coordinates of the i-th wavenumber domain.

[0162] Optionally, each element (wavenumber domain coordinate) in the list of wavenumber domain coordinates can be normalized to the wavenumber. A list of wavenumber domain coordinates can be represented as in,

[0163] Optionally, each element (wavenumber domain coordinate) in the list of wavenumber domain coordinates can be normalized to the wavenumber domain quantization interval (Δ). h Δ v In this context, the wavenumber domain coordinates in the horizontal direction are normalized to the horizontal quantization interval Δ. h The wavenumber domain coordinates in the vertical direction are normalized to the quantization interval Δ in the vertical direction. v A list of wavenumber domain coordinates can be represented as in, or or

[0164] Optionally, the quantization interval Δ in the horizontal direction h The value can be predefined by the protocol or explicitly configured to the terminal by the network device.

[0165] Optionally, Among them, A h This refers to the horizontal aperture of the antenna array (two-dimensional array) of the network device. In this case, for Integers between, that is

[0166] Optionally, the quantization interval in the horizontal direction Or horizontal diameter A h It can be explicitly configured by the network device for the terminal.

[0167] Optionally, the value of the quantization interval in the vertical direction Δ v It can be predefined by the protocol or explicitly configured to the terminal by the network device.

[0168] Optionally, Among them, A v This refers to the vertical aperture of the antenna array (two-dimensional array) of the network device. In this case, for Integers between, that is

[0169] Optionally, the quantization interval in the vertical direction Or vertical diameter A v It can be explicitly configured by the network device for the terminal.

[0170] It is understandable that the quantization interval and The wavenumber domain corresponds to the Nyquist sampling rate. Therefore, quantizing the wavenumber domain at this quantization interval can achieve a balance between performance (accuracy) and signaling overhead.

[0171] In the above embodiment, the L wavenumber domain coordinates can be normalized to the wavenumber. Alternatively, wavenumber domain quantization intervals can reduce the signaling overhead of wavenumber domain coordinate configuration. On the other hand, they make the configured wavenumber domain coordinates independent of the carrier frequency, enabling wireless communication systems operating on different carrier frequencies to share a common implementation (such as in protocol stack software development). This consistency can reduce costs.

[0172] In some embodiments, the antenna array of the network device is a one-dimensional array, and the network device configures a wavenumber domain coordinate list for the terminal using first information. For example, the wavenumber domain coordinate list is... or

[0173] In some embodiments, the antenna array of the network device is a one-dimensional array, and the network device configures a wavenumber domain coordinate list and a wavenumber domain quantization interval Δ for the terminal using first information. For example, the wavenumber domain coordinate list is...

[0174] In some embodiments, the antenna array of the network device is a one-dimensional array, and the network device configures a wavenumber domain coordinate list and the aperture A of the one-dimensional array for the terminal using first information. For example, the wavenumber domain coordinate list is...

[0175] In some embodiments, the antenna array of the network device is a two-dimensional array, and the network device configures a wavenumber domain coordinate list for the terminal using first information. For example, the wavenumber domain coordinate list is... or

[0176] In some embodiments, the antenna array of the network device is a two-dimensional array, and the network device configures a wavenumber domain coordinate list and a horizontal quantization interval Δ for the terminal using first information. h and the quantization interval Δ in the vertical direction v For example, the list of wavenumber domain coordinates is as follows:

[0177] In some embodiments, the antenna array of the network device is a two-dimensional array, and the network device configures a wavenumber domain coordinate list and a horizontal aperture A for the terminal using the first information. h and vertical aperture A v For example, the list of wavenumber domain coordinates is as follows:

[0178] In some embodiments, the configuration signaling of the first information may be at least one of Downlink Control Information (DCI), Medium Access Control (MAC CE), and Radio Resource Control (RRC).

[0179] In some embodiments, the terminal receives first information sent by the network device and obtains L wavenumber domain coordinates configured by the network device.

[0180] Step S2102: The terminal determines the spatial orthogonal basis based on the L wavenumber domain coordinates indicated in the first information.

[0181] In some embodiments, the terminal determines a spatial orthogonal basis, denoted as B, based on L wavenumber domain coordinates configured in the network device. The spatial orthogonal basis B includes L spatial basis vectors, each corresponding one-to-one with one of the L wavenumber domain coordinates. Each column in the spatial orthogonal basis B is a spatial basis vector, and the i-th spatial basis vector in the spatial orthogonal basis B corresponds to the i-th wavenumber domain coordinate among the L wavenumber domain coordinates. Optionally, if the L wavenumber domain coordinates are normalized to wavenumber... Alternatively, the wavenumber domain quantization interval can be configured and assigned to the terminal, which will then restore the L wavenumber domain coordinates to their original coordinates.

[0182] In some embodiments, if the antenna array of the network device is a one-dimensional array, the spatial orthogonal basis can be represented as a matrix. Where N represents the number of antennas or antenna ports in one polarization direction of the network device's antenna array. Let r be the i-th spatial basis vector, where r = [r1 r2 … r2 ... r3] N ] T This represents the coordinates of each antenna or antenna port in the antenna array of a network device, i.e., r n Let n be the coordinates of the nth antenna or antenna port in the antenna array, where n = 1, 2, ..., N.

[0183] It should be noted that if the one-dimensional array is a uniform linear array (ULA), then r n = (n-1)d, where d is the spacing between adjacent antennas or adjacent antenna ports, then the i-th spatial basis vector can be expressed as

[0184] In some embodiments, if the antenna array of the network device is a two-dimensional array, the spatial orthogonal basis can be represented as a matrix. Where N1 is the number of antennas or antenna ports in the horizontal direction of the network device's antenna array in one polarization direction, and N2 is the number of antennas or antenna ports in the vertical direction of the network device's antenna array in one polarization direction. Let be the i-th spatial basis vector.

[0185] Alternatively, if the antenna indexing order in the array is column-first, then row-first, then the i-th spatial basis vector can be represented as: This represents the Kronecker product operation.

[0186] Alternatively, if the antenna indexing order in the array is row-first, then column-first, then the i-th spatial basis vector can be represented as:

[0187] in, This represents the coordinates of the antenna or antenna port in the n2th row and n1st column of the antenna array of the network device, where n1 = 1, 2, ..., N1 and n2 = 1, 2, ..., N2.

[0188] It should be noted that if the two-dimensional array is a uniform planar array (UPA), then d h d represents the spacing between adjacent antennas or adjacent antenna ports in the horizontal direction. v This represents the spacing between adjacent antennas or adjacent antenna ports in the vertical direction. Taking the antenna indexing order as column-first, row-first as an example, the i-th spatial basis vector can be represented as:

[0189] In the above embodiments, the network device configures the wavenumber domain coordinates of the channel for the terminal. The terminal can calculate the corresponding spatial orthogonal basis based on the wavenumber domain coordinates configured by the network device. Therefore, the network device does not need to configure some candidate spatial orthogonal bases for the terminal, thereby reducing overhead. The saved overhead can be used to quantize the projection coefficients. High-precision quantization coefficients will bring more accurate CSI.

[0190] Step S2103: The terminal determines the first coefficient matrix based on the spatial orthogonal basis and the first downlink precoding matrix.

[0191] In some embodiments, the network device sends a first reference signal (such as CSI-RS) to the terminal, the terminal measures the first reference signal sent by the network device, determines the channel matrix of the downlink channel, and determines a first downlink precoding matrix, denoted as V, based on the channel matrix of the downlink channel.

[0192] Alternatively, if the antenna array of the network device is a one-dimensional single-polarization array, N represents the number of antennas or antenna ports in the antenna array of the network device in one polarization direction. This is the rank of the channel matrix of the downlink channel, which is also the number of data layers.

[0193] Alternatively, if the antenna array of the network device is a one-dimensional dual-polarized array, In this matrix, the upper half (first N rows) of the first downlink precoding matrix V corresponds to the first polarization direction, and the lower half (last N rows) corresponds to the second polarization direction.

[0194] Alternatively, if the antenna array of the network device is a two-dimensional single-polarization array, N1 represents the number of antennas or antenna ports in the horizontal direction of the network device's antenna array in one polarization direction, and N2 represents the number of antennas or antenna ports in the vertical direction of the network device's antenna array in one polarization direction.

[0195] Optionally, if the antenna array of the network device is a two-dimensional dual-polarized array, The upper half (first N1N2 rows) of the first downlink precoding matrix V corresponds to the first polarization direction, and the lower half (last N1N2 rows) corresponds to the second polarization direction.

[0196] Optionally, when r = 1, the first downlink precoding matrix can be described as the first downlink precoding vector.

[0197] In some embodiments, the first downlink precoding matrix V is projected onto a spatial orthogonal basis B to determine the first coefficient matrix. The following three embodiments illustrate the first coefficient matrix.

[0198] Example 1:

[0199] If the antenna array of the network device is a single-polarization array (such as a one-dimensional or two-dimensional single-polarization array), the i-th row in the first coefficient matrix represents the projection coefficients of the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis.

[0200] For example, Let be the first coefficient matrix. Here, i is an integer from 1 to L.

[0201] Example 2:

[0202] If the antenna array of the network device is a dual-polarization array (such as a one-dimensional or two-dimensional dual-polarization array), the i-th row of the first coefficient matrix represents the projection coefficients of the submatrix corresponding to the first polarization direction in the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis, and the L+i-th row represents the projection coefficients of the submatrix corresponding to the second polarization direction in the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis.

[0203] For example, I1 is the first coefficient matrix, and I2 is a 2×2 identity matrix. The upper half (first L rows) of the first coefficient matrix corresponds to the first polarization direction, and the lower half (last L rows) corresponds to the second polarization direction.

[0204] The upper half (first L rows) of the first coefficient matrix can be described as the coefficient matrix corresponding to the first polarization direction, representing the projection coefficients of the submatrix corresponding to the first polarization direction in the first downlink precoding matrix (i.e., the upper half of the first downlink precoding matrix) onto the spatial orthogonal basis (L spatial basis vectors).

[0205] The lower half (last L rows) of the first coefficient matrix can be described as the coefficient matrix corresponding to the second polarization direction, representing the projection coefficients of the submatrix corresponding to the second polarization direction in the first downlink precoding matrix (i.e., the lower half of the first downlink precoding matrix) onto the spatial orthogonal basis (L spatial basis vectors).

[0206] For a one-dimensional antenna array, the upper half (the first L rows) of the first coefficient matrix represents the first downlink precoding matrix. The upper half (first N rows) of the first coefficient matrix is ​​projected onto the spatial orthogonal basis as projection coefficients. Specifically, the i-th row of the upper half (first L rows) of the first coefficient matrix represents the first downlink precoding matrix. The upper half (first N rows) of the first coefficient matrix represents the projection coefficients onto the i-th spatial basis vector in the spatial orthogonal basis; the lower half (last L rows) of the first coefficient matrix represents the first downlink precoding matrix. The lower half (last N rows) of the first coefficient matrix is ​​projected onto the projection coefficients of the spatial orthogonal basis. Specifically, the i-th row (i.e., the L+i-th row in the lower half (last L rows) of the first coefficient matrix represents the first downlink precoding matrix. The projection coefficients of the lower half (last N rows) of the vector onto the i-th spatial basis vector in the spatial orthogonal basis.

[0207] For a two-dimensional antenna array, the upper half (the first L rows) of the first coefficient matrix represents the first downlink precoding matrix. The upper half (the first N1N2 rows) of the first coefficient matrix is ​​projected onto the spatial orthogonal basis as projection coefficients. Specifically, the i-th row of the upper half (the first L rows) of the first coefficient matrix represents the first downlink precoding matrix. The upper half (the first N1N2 rows) of the first coefficient matrix represents the projection coefficients onto the i-th spatial basis vector in the spatial orthogonal basis; the lower half (the last L rows) of the first coefficient matrix represents the first downlink precoding matrix. The lower half (the last N1N2 rows) of the first coefficient matrix is ​​projected onto the spatial orthogonal basis as projection coefficients. Specifically, the i-th row (i.e., the L+i-th row in the first coefficient matrix) of the lower half (the last L rows) represents the first downlink precoding matrix. The projection coefficients of the lower half (the last N1N2 rows) onto the i-th spatial basis vector in the spatial orthogonal basis.

[0208] Example 3:

[0209] If the antenna array of the network device is a dual-polarization array (such as a one-dimensional or two-dimensional dual-polarization array), the i-th row of the first coefficient matrix is ​​determined by the projection coefficients of the sub-matrices corresponding to the first polarization direction and the sub-matrices corresponding to the second polarization direction in the first downlink precoding matrix, which are respectively projected onto the i-th spatial basis vector in the spatial orthogonal basis.

[0210] For example, the coefficient matrix mentioned above Corresponding to the two polarization directions, the upper half (first L rows) of the coefficient matrix c corresponds to the first polarization direction, and the lower half (last L rows) corresponds to the second polarization direction. In this embodiment, the two polarization directions can correspond to the same coefficient matrix, that is... in, This is the first coefficient matrix, which is the coefficient matrix corresponding to both polarization directions. Let be the first vector, containing the inter-polarity coefficients of r data layers, and ⊙ denotes the Khatri-Rao product operation. It should be noted that the first coefficient matrix... It is determined by the projection coefficients of the submatrices corresponding to the first polarization direction and the submatrices corresponding to the second polarization direction in the first downlink precoding matrix, projected onto the spatial orthogonal basis, that is, by the coefficient matrix c. Specifically, the first coefficient matrix... The i-th row in the matrix is ​​determined by the projection coefficients of the submatrix corresponding to the first polarization direction and the submatrix corresponding to the second polarization direction in the first down row precoding matrix, which are projected onto the i-th spatial basis vector in the spatial orthogonal basis.

[0211] In Example 3, the terminal determines the first coefficient matrix. and the first vector c p .

[0212] According to Example 3, for each data layer, the projection coefficients in the two polarization directions can be proportional. In this case, the projection coefficients in the two polarization directions differ by a scaling factor (i.e., the inter-polarization coefficient). Optionally, the scaling factor corresponding to different data layers is different.

[0213] Alternatively, when r = 1, the first coefficient matrix can be described as the first coefficient vector.

[0214] Step S2104: The terminal quantizes the first coefficient matrix to determine the second coefficient matrix.

[0215] In some embodiments, according to Examples 1 and 2, the first coefficient matrix is ​​denoted as c. The terminal quantizes the first coefficient matrix c to determine the second coefficient matrix, denoted as Q(c). Here, Q(·) is a quantization function, which can represent uniform quantization or non-uniform quantization; it can represent absolute quantization or relative quantization.

[0216] Optionally, the terminal needs to report the second coefficient matrix Q(c) to the network device. The terminal reporting the second coefficient matrix Q(c) to the network device can be interpreted as the terminal reporting all elements in the second coefficient matrix Q(c), or reporting a portion of the elements in the second coefficient matrix Q(c) (e.g., non-zero elements or rows where not all elements are zero), or parameters used to determine the sparse matrix corresponding to the second coefficient matrix Q(c).

[0217] In some embodiments, according to embodiment 3, the first coefficient matrix is ​​denoted as Terminal to the first coefficient matrix Quantization is performed to determine the second coefficient matrix, denoted as... And, for the first vector c p Quantization is performed to determine the second vector, denoted as Q(c). p ).

[0218] Optionally, the terminal needs to report the second coefficient matrix to the network device. Second vector Q(c) p The terminal reports the second coefficient matrix to the network device. This can be interpreted as the terminal reporting the second coefficient matrix. All elements, or the reported second coefficient matrix Some elements in the matrix (e.g., non-zero elements or rows where not all elements are zero), or elements used to determine the second coefficient matrix. The parameters of the corresponding sparse matrix. The terminal reports the second vector Q(c) to the network device. p This can be interpreted as the terminal reporting the second vector Q(c) to the network device. p All elements in ).

[0219] Alternatively, when r = 1, the second coefficient matrix can be described as the second coefficient vector.

[0220] Step S2105: The terminal sends the second information to the network device.

[0221] In some embodiments, the second information is used by the network device to determine the third coefficient matrix, which is the second coefficient matrix or a sparse matrix corresponding to the second coefficient matrix.

[0222] Optionally, the terminal reports the second coefficient matrix Q(c) to the network device using the second information.

[0223] Optionally, the terminal reports the second coefficient matrix to the network device using the second information. Second vector Q(c) p ).

[0224] In some embodiments, according to Examples 1 and 2, the second information includes (or indicates) one of the following:

[0225] Second coefficient matrix;

[0226] Rows in the second coefficient matrix where not all elements are zero;

[0227] The row index corresponding to the element with the largest modulus in each column of the second coefficient matrix.

[0228] Optionally, if the second information contains the second coefficient matrix Q(c), then the network device obtains the second coefficient matrix Q(c), and the third coefficient matrix is ​​the second coefficient matrix Q(c).

[0229] Optionally, if the second information contains rows in the second coefficient matrix Q(c) where not all elements are zero (i.e., non-zero rows), then the network device obtains the second coefficient matrix Q(c) based on the non-zero rows, and the third coefficient matrix is ​​the second coefficient matrix Q(c).

[0230] Optionally, if the L wavenumber domain coordinates in the wavenumber domain coordinate list are arranged in descending order of the power corresponding to each wavenumber domain coordinate, then there may be a situation where the last row of the second coefficient matrix Q(c) is zero (0 < L < L). in, The terminal reports the non-zero part of the second coefficient matrix Q(c). That is, the first L-L0 rows of the second coefficient matrix Q(c). If the second information contains non-zero parts... Then the network device is based on the non-zero part Obtain the second coefficient matrix Q(c).

[0231] Optionally, if the second information contains the row index corresponding to the element with the largest modulus in each column of the second coefficient matrix Q(c), i.e., r row indices, then the network device determines the sparse matrix corresponding to the second coefficient matrix Q(c) based on the r row indices, and the third coefficient matrix is ​​the sparse matrix corresponding to the second coefficient matrix Q(c). The third coefficient matrix is ​​a sparse matrix with one non-zero element in each column. Specifically, each column of the sparse matrix corresponds to a row index, and the element at the corresponding row index position in each column of the sparse matrix is ​​1, while other elements are 0. For example, assume that the row index corresponding to the l-th column (l-th layer) is k. l Then the l-th column of the sparse matrix contains only the k-th column. l The kth (i.e., the kth) l The element in the l-th row is 1, and all other elements in the l-th column are 0; 1 ≤ l ≤ r, 1 ≤ k l ≤L.

[0232] In the above embodiments, the second information may only report the non-zero rows in the second coefficient matrix, or only report the row index (i.e., r row indices) corresponding to the element with the largest modulus in each column of the second coefficient matrix. Compared with reporting all elements in the second coefficient matrix, the feedback overhead of the second information can be reduced.

[0233] In some embodiments, according to embodiment 3, the second information includes (or indicates) a second vector, and one of the following:

[0234] Second coefficient matrix;

[0235] Rows in the second coefficient matrix where not all elements are zero;

[0236] The row index corresponding to the element with the largest modulus in each column of the second coefficient matrix.

[0237] Optionally, if the second information contains the second vector Q(c) p Then the network device obtains the second vector Q(c). p ).

[0238] Optionally, if the second information contains a second coefficient matrix Then the network device obtains the second coefficient matrix. The third coefficient matrix is ​​the second coefficient matrix.

[0239] Optionally, if the second information contains a second coefficient matrix If the elements in the matrix are not all zero (non-zero rows), then the network device obtains the second coefficient matrix based on the non-zero rows. The third coefficient matrix is ​​the second coefficient matrix.

[0240] Optionally, if the L wavenumber domain coordinates in the wavenumber domain coordinate list are arranged in descending order of the power corresponding to each wavenumber domain coordinate, then a second coefficient matrix may exist. The last line of the string, 0 < L, represents zero, that is... in, Terminal reports the second coefficient matrix The non-zero part That is, the second coefficient matrix The first L-L0 rows in the [database]. If the second information contains a non-zero portion. Then the network device is based on the non-zero part Obtain the second coefficient matrix

[0241] Optionally, if the second information contains a second coefficient matrix Given the row index corresponding to the element with the largest modulus in each column, i.e., r row indices, the network device determines the second coefficient matrix based on these r row indices. The corresponding sparse matrix, the third coefficient matrix is ​​the second coefficient matrix The corresponding sparse matrix. The third coefficient matrix is ​​a sparse matrix where each column has a non-zero element. Specifically, each column of the sparse matrix corresponds to a row index, and the element at the corresponding row index in each column of the sparse matrix is ​​1, while all other elements are 0. For example, suppose the row index corresponding to the l-th column (l-th layer) is k. l Then the l-th column of the sparse matrix contains only the k-th column. l The kth (i.e., the kth) l The element in the l-th row is 1, and all other elements in the l-th column are 0; 1 ≤ l ≤ r, 1 ≤ k l ≤L.

[0242] In the above embodiments, the second information may only report the non-zero rows in the second coefficient matrix, or only report the row index (i.e., r row indices) corresponding to the element with the largest modulus in each column of the second coefficient matrix. Compared with reporting all elements in the second coefficient matrix, the feedback overhead of the second information can be reduced.

[0243] Furthermore, for the antenna array of the network device to be a dual-polarization array, according to embodiment 3, it is only necessary to report a coefficient matrix that corresponds to both polarization directions and the inter-polarization coefficients of each data layer. Compared with embodiment 2, it is not necessary to report the coefficient matrix corresponding to each polarization direction separately. Therefore, the feedback overhead of the second information can be reduced.

[0244] Optionally, the network device receives the second information sent by the terminal and determines the third coefficient matrix based on the second information. Optionally, the third coefficient matrix is ​​the second coefficient matrix or a sparse matrix corresponding to the second coefficient matrix.

[0245] Alternatively, when r = 1, the third coefficient matrix can be described as the third coefficient vector.

[0246] In some embodiments, the transmission of the second information can be accomplished through at least one of the Physical Uplink Control Channel (PUCCH), Physical Uplink Shared Channel (PUSCH), Physical Sidelink Control Channel (PSCCH), and Physical Sidelink Shared Channel (PSSCH).

[0247] Step S2106: The network device determines the spatial orthogonal basis based on L wavenumber domain coordinates.

[0248] In some embodiments, the network device configures L wavenumber domain coordinates for the terminal, and the terminal determines a spatial orthogonal basis B based on the L wavenumber domain coordinates. Similarly, the network device determines the spatial orthogonal basis B based on the L wavenumber domain coordinates. The spatial orthogonal basis B includes L spatial basis vectors, and each of the L spatial basis vectors corresponds one-to-one with the L wavenumber domain coordinates. Each column in the spatial orthogonal basis B is a spatial basis vector, and the i-th spatial basis vector in the spatial orthogonal basis B corresponds to the i-th wavenumber domain coordinate in the L wavenumber domain coordinates.

[0249] Optionally, the alternative implementation of the network device determining the spatial orthogonal basis B based on L wavenumber domain coordinates is the same as the alternative implementation of the terminal determining the spatial orthogonal basis B based on L wavenumber domain coordinates. The alternative implementation of step S2106 can be found in the alternative implementation of step S2102 and other related parts of the specification, and will not be repeated here.

[0250] Step S2107: The network device determines the third coefficient matrix based on the second information.

[0251] The optional implementations of step S2107 can be found in the optional implementations of step S2105 and other related parts of the specification, and will not be repeated here.

[0252] For ease of description, the third coefficient matrix is ​​denoted as...

[0253] Optionally, the network device determines the third coefficient matrix based on the second information.

[0254] Optionally, the network device determines the third coefficient matrix based on the second information. Let Q(c) be the sparse matrix.

[0255] Optionally, the network device determines the second vector Q(c) based on the second information. p ) and the third coefficient matrix

[0256] Optionally, the network device determines the second vector Q(c) based on the second information. p ) and the third coefficient matrix for The corresponding sparse matrix.

[0257] Step S2108: The network device determines the second downlink precoding matrix based on the spatial orthogonal basis and the third coefficient matrix.

[0258] Network devices are based on the spatial orthogonal basis B and the third coefficient matrix. Determine the second downlink precoding matrix, denoted as

[0259] Alternatively, if the antenna array of the network device is a one-dimensional single-polarization array, N represents the number of antennas or antenna ports in the antenna array of the network device in one polarization direction. This is the rank of the channel matrix of the downlink channel, which is also the number of data layers.

[0260] Alternatively, if the antenna array of the network device is a one-dimensional dual-polarized array, Second downlink precoding matrix The upper half (first N rows) corresponds to the first polarization direction, and the lower half (last N rows) corresponds to the second polarization direction.

[0261] Alternatively, if the antenna array of the network device is a two-dimensional single-polarization array, N1 represents the number of antennas or antenna ports in the horizontal direction of the network device's antenna array in one polarization direction, and N2 represents the number of antennas or antenna ports in the vertical direction of the network device's antenna array in one polarization direction.

[0262] Optionally, if the antenna array of the network device is a two-dimensional dual-polarized array, Second downlink precoding matrix The upper half (the first N1N2 rows) corresponds to the first polarization direction, and the lower half (the last N1N2 rows) corresponds to the second polarization direction.

[0263] Alternatively, when r = 1, the second downlink precoding matrix can be described as the second downlink precoding vector.

[0264] In some embodiments, according to Example 1, if the antenna array of the network device is a single-polarization array (such as a one-dimensional or two-dimensional single-polarization array), then

[0265] Optionally, according to Embodiment 1, the third coefficient matrix

[0266] Optionally, according to Embodiment 1, the third coefficient matrix Let Q(c) be the sparse matrix.

[0267] In some embodiments, according to embodiment 2, if the antenna array of the network device is a dual-polarized array (such as a one-dimensional or two-dimensional dual-polarized array), then

[0268] Optionally, according to Embodiment 2, the third coefficient matrix

[0269] Optionally, according to Embodiment 2, the third coefficient matrix Let Q(c) be the sparse matrix.

[0270] Optionally, according to embodiment 3, if the antenna array of the network device is a dual-polarized array (such as a one-dimensional or two-dimensional dual-polarized array), then Q(c p ) is the second vector.

[0271] Optionally, according to Embodiment 3, the third coefficient matrix It is determined by the projection coefficients of the submatrix corresponding to the first polarization direction and the submatrix corresponding to the second polarization direction in the first downlink precoding matrix V, which are projected onto the spatial orthogonal basis.

[0272] Optionally, according to Embodiment 3, the third coefficient matrix for The corresponding sparse matrix.

[0273] In some embodiments, the network device performs downlink scheduling and / or data transmission based on a second downlink precoding matrix.

[0274] In the above embodiments, a unified codebook design scheme in the wavenumber domain is proposed. Compared with the existing Type 2 codebook scheme, the embodiments of this disclosure calculate the corresponding spatial orthogonal basis through the wavenumber domain coordinates configured in the network device, thereby providing more accurate spatial CSI and higher spectral efficiency, and also greatly reducing feedback overhead.

[0275] In some embodiments, the names of information, etc., are not limited to the names described in the embodiments. Terms such as "information", "message", "signal", "signaling", "report", "configuration", "feedback", "indication", "instruction", "command", "channel", "parameter", "domain", "field", "symbol", "symbol", "codebook", "codeword", "codepoint", and "bit" can be used interchangeably.

[0276] In some embodiments, the terms "codebook," "codeword," and "precoding matrix" can be used interchangeably. For example, a codebook can be a collection of one or more codewords / precoding matrices.

[0277] In some embodiments, the terms "uplink", "uplink", and "physical uplink" can be used interchangeably, as can the terms "downlink", "downlink", and "physical downlink", as well as the terms "sidelink", "sidelink", "sidelink communication", "sidelink communication", "direct connection", "direct link", "direct communication", and "direct link communication".

[0278] In some embodiments, the terms “downlink control information (DCI),” “downlink (DL) assignment,” “DL DCI,” “uplink (UL) grant,” and “UL DCI” can be used interchangeably.

[0279] In some embodiments, terms such as "physical downlink shared channel (PDSCH)" and "DL data" can be used interchangeably, as can terms such as "physical uplink shared channel (PUSCH)" and "UL data".

[0280] In some embodiments, the terms "data layer", "the number of layers", and "rank" can be used interchangeably.

[0281] In some embodiments, "acquire," "get," "obtain," "receive," "transmit," "bidirectional transmission," and "send and / or receive" can be used interchangeably and can be interpreted as receiving from other entities, acquiring from protocols, acquiring from higher layers, obtaining through self-processing, or autonomous implementation. Protocols include, for example, at least one of the 3GPP protocol, Wi-Fi protocol, and audio and / or video protocols.

[0282] In some embodiments, terms such as “send,” “transmit,” “report,” “distribute,” “transfer,” “bidirectional transmission,” “send and / or receive” can be used interchangeably.

[0283] In some embodiments, terms such as "certain," "preset," "default," "set," "indicated," "a certain," "any," and "first" can be used interchangeably. "Certain A," "preset A," "default A," "set A," "indicated A," "a certain A," "any A," and "first A" can be interpreted as A pre-defined in a protocol or the like, or as A obtained through setting, configuration, or instruction, or as specific A, a certain A, any A, or first A, but are not limited thereto.

[0284] The communication method involved in the embodiments of this disclosure may include at least one of steps S2101 to S2108. For example, step S2101 may be implemented as an independent embodiment, step S2101 + step S2102 may be implemented as an independent embodiment, step S2103 may be implemented as an independent embodiment, step S2105 may be implemented as an independent embodiment, step S2101 + step S2102 + step S2103 may be implemented as an independent embodiment, step S2101 + step S2102 + step S2103 + step S2104 + step S2105 may be implemented as an independent embodiment, step S2106 may be implemented as an independent embodiment, step S2107 may be implemented as an independent embodiment, step S2105 + S2107 may be implemented as an independent embodiment, and step S2105 + step S2106 + step S2107 + step S2108 may be implemented as an independent embodiment, but is not limited thereto.

[0285] In some embodiments, steps S2101 to S2107 may be performed in an alternate order or simultaneously.

[0286] In some embodiments, steps S2103 to S2108 are optional, and one or more of these steps may be omitted or substituted in different embodiments.

[0287] In some embodiments, steps S2101 to S2105 and steps S2107 to S2108 are optional, and one or more of these steps may be omitted or substituted in different embodiments.

[0288] In some embodiments, steps S2106 to S2108 are optional, and one or more of these steps may be omitted or substituted in different embodiments.

[0289] In some embodiments, steps S2101 to S2104 are optional, and one or more of these steps may be omitted or substituted in different embodiments.

[0290] In some embodiments, the steps and their optional implementations in other embodiments described before or after this embodiment, as well as other related parts in the specification, can be referred to, and will not be repeated here.

[0291] Figure 2B is an interactive schematic diagram of a communication method according to an embodiment of the present disclosure. As shown in Figure 2B, the embodiments of the present disclosure relate to a communication method, which includes:

[0292] Step S2201: The network device sends the first information to the terminal.

[0293] The optional implementation of step S2201 can be found in the optional implementation of step S2101 in Figure 2A and other related parts in the specification, which will not be repeated here.

[0294] Step S2202: The terminal determines the spatial orthogonal basis based on the L wavenumber domain coordinates indicated in the first information.

[0295] The optional implementation of step S2202 can be found in the optional implementation of step S2102 in Figure 2A and other related parts in the specification, which will not be repeated here.

[0296] Step S2203: The terminal determines the first coefficient vector based on the spatial orthogonal basis and the first downlink precoding vector.

[0297] In some embodiments, the network device sends a first reference signal (such as CSI-RS) to the terminal. The terminal measures the first reference signal sent by the network device, determines the channel matrix of the downlink channel, and determines a first downlink precoding vector, denoted as V, based on the channel matrix of the downlink channel. The rank r of the channel matrix is ​​1, corresponding to one data layer.

[0298] Alternatively, if the antenna array of the network device is a one-dimensional single-polarization array, N represents the number of antennas or antenna ports in the antenna array of the network device in one polarization direction.

[0299] Alternatively, if the antenna array of the network device is a one-dimensional dual-polarized array, In this context, the upper half (the first i elements) of the first downlink precoding vector V corresponds to the first polarization direction, and the lower half (the last i elements) corresponds to the second polarization direction.

[0300] Alternatively, if the antenna array of the network device is a two-dimensional single-polarization array, N1 represents the number of antennas or antenna ports in the horizontal direction of the network device's antenna array in one polarization direction, and N2 represents the number of antennas or antenna ports in the vertical direction of the network device's antenna array in one polarization direction.

[0301] Optionally, if the antenna array of the network device is a two-dimensional dual-polarized array, The upper half (the first N1N2 elements) of the first downlink precoding vector V corresponds to the first polarization direction, and the lower half (the last N1N2 elements) corresponds to the second polarization direction.

[0302] In some embodiments, the first downlink precoding vector V is projected onto a spatial orthogonal basis B to determine the first coefficient vector. The following three embodiments illustrate the first coefficient vector.

[0303] Example 1:

[0304] If the antenna array of the network device is a single-polarization array (such as a one-dimensional or two-dimensional single-polarization array), the i-th element in the first coefficient vector represents the projection coefficient of the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis.

[0305] For example, Let be the first coefficient vector. Here, i is an integer from 1 to L.

[0306] Example 2:

[0307] If the antenna array of the network device is a dual-polarization array (such as a one-dimensional or two-dimensional dual-polarization array), the i-th element in the first coefficient vector represents the projection coefficient of the sub-vector corresponding to the first polarization direction in the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis, and the L+i-th element represents the projection coefficient of the sub-vector corresponding to the second polarization direction in the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis.

[0308] For example, Let I be the first coefficient vector, and let I2 be the identity matrix of size 2×2. The upper half (first L elements) of the first coefficient vector corresponds to the first polarization direction, and the lower half (last L elements) corresponds to the second polarization direction.

[0309] The upper half (first L elements) of the first coefficient vector can be described as the coefficient vector corresponding to the first polarization direction, representing the projection coefficients of the sub-vector corresponding to the first polarization direction in the first downlink precoding vector (i.e., the upper half of the first downlink precoding vector) onto the spatial orthogonal basis (L spatial basis vectors).

[0310] The lower half (the last L elements) of the first coefficient vector can be described as the coefficient vector corresponding to the second polarization direction, representing the projection coefficients of the sub-vector corresponding to the second polarization direction in the first downlink precoding vector (that is, the lower half of the first downlink precoding vector) onto the spatial orthogonal basis (L spatial basis vectors).

[0311] For a one-dimensional antenna array, the upper half (the first L elements) of the first coefficient vector represents the first downlink precoding vector. The upper half (first N elements) of the first coefficient vector is projected onto the spatial orthogonal basis as projection coefficients. Specifically, the i-th element in the upper half (first L elements) of the first coefficient vector represents the first downlink precoding vector. The upper half (first N elements) of the first coefficient vector is projected onto the i-th spatial basis vector in the spatial orthogonal basis as projection coefficients; the lower half (last L elements) of the first coefficient vector represents the first downlink precoding vector. The projection coefficients of the lower half (the last N elements) of the first coefficient vector onto the spatial orthogonal basis are specifically defined as follows: the i-th element (i.e., the L+i-th element in the first coefficient vector) of the lower half (the last L elements) of the first coefficient vector represents the first downlink precoding vector. The projection coefficients of the lower half (the last N elements) of the vector onto the i-th spatial basis vector in the spatial orthogonal basis.

[0312] For a two-dimensional antenna array, the upper half (the first L elements) of the first coefficient vector represents the first downlink precoding vector. The upper half (the first N1N2 elements) of the first coefficient vector is projected onto the spatial orthogonal basis as projection coefficients. Specifically, the i-th element in the upper half (the first L elements) of the first coefficient vector represents the first downlink precoding vector. The upper half (the first N1N2 elements) of the first coefficient vector is projected onto the i-th spatial basis vector in the spatial orthogonal basis as projection coefficients; the lower half (the last L elements) of the first coefficient vector represents the first downlink precoding vector. The lower half (the last N1N2 elements) of the first coefficient vector is projected onto the spatial orthogonal basis as projection coefficients. Specifically, the i-th element (i.e., the L+i-th element in the first coefficient vector) of the lower half (the last L elements) represents the first downlink precoding vector. The projection coefficients of the lower half (the last N1N2 elements) onto the i-th spatial basis vector in the spatial orthogonal basis.

[0313] Example 3:

[0314] If the antenna array of the network device is a dual-polarization array (such as a one-dimensional or two-dimensional dual-polarization array), the i-th element in the first coefficient vector is determined by the projection coefficients of the sub-vectors corresponding to the first polarization direction and the sub-vectors corresponding to the second polarization direction in the first downlink precoding vector, which are respectively projected onto the i-th spatial basis vector in the spatial orthogonal basis.

[0315] For example, the coefficient vector mentioned above Corresponding to the two polarization directions, the upper half (the first L elements) of the coefficient vector c corresponds to the first polarization direction, and the lower half (the last L elements) corresponds to the second polarization direction. In this embodiment, the two polarization directions can correspond to the same coefficient vector, that is... in, This is the first coefficient vector, which is the coefficient vector corresponding to both polarization directions. Let be the first vector, containing the inter-polarization coefficients of a data layer, where ⊙ represents the Khatri-Rao product operation. It should be noted that the first coefficient vector... It is determined by the projection coefficients of the sub-vectors corresponding to the first polarization direction and the sub-vectors corresponding to the second polarization direction in the first downlink precoding vector, projected onto the spatial orthogonal basis, that is, by the coefficient vector c. Specifically, the first coefficient vector... The i-th element is determined by the projection coefficients of the sub-vectors corresponding to the first polarization direction and the sub-vectors corresponding to the second polarization direction in the first downlink precoding vector, which are projected onto the i-th spatial basis vector in the spatial orthogonal basis.

[0316] In Example 3, the terminal determines the first coefficient vector. and the first vector c p .

[0317] According to Example 3, for this data layer, the projection coefficients in the two polarization directions can be proportional. In this case, the projection coefficients in the two polarization directions differ by a proportionality coefficient (i.e., the inter-polarization coefficient).

[0318] Step S2204: The terminal quantizes the first coefficient vector to determine the second coefficient vector.

[0319] In some embodiments, according to Examples 1 and 2, the first coefficient vector is denoted as c. The terminal quantizes the first coefficient vector c to determine the second coefficient vector, denoted as Q(c). Here, Q(·) is a quantization function, which can represent uniform quantization or non-uniform quantization; it can represent absolute quantization or relative quantization.

[0320] Optionally, the terminal needs to report the second coefficient vector Q(c) to the network device. The terminal reporting the second coefficient vector Q(c) to the network device can be interpreted as the terminal reporting all elements in the second coefficient vector Q(c), or reporting a portion of the elements in the second coefficient vector Q(c) (e.g., non-zero elements), or parameters used to determine the sparse vector corresponding to the second coefficient vector Q(c).

[0321] In some embodiments, according to embodiment 3, the first coefficient vector is denoted as Terminal for the first coefficient vector Quantization is performed to determine the second coefficient vector, denoted as... And, for the first vector c p Quantization is performed to determine the second vector, denoted as Q(c). p ).

[0322] Optionally, the terminal needs to report the second coefficient vector to the network device. Second vector Q(c) p The terminal reports the second coefficient vector to the network device. This can be interpreted as the terminal reporting the second coefficient vector. All elements, or the reported second coefficient vector Some elements (e.g., non-zero elements) or used to determine the second coefficient vector The parameters of the corresponding sparse vector. The terminal reports the second vector Q(c) to the network device. p This can be interpreted as the terminal reporting the second vector Q(c) to the network device. p All elements in ).

[0323] Step S2205: The terminal sends the second information to the network device.

[0324] In some embodiments, the second information is used by the network device to determine a third coefficient vector, which is the second coefficient vector or a sparse vector corresponding to the second coefficient vector.

[0325] Optionally, the terminal reports the second coefficient vector Q(c) to the network device using the second information.

[0326] Optionally, the terminal reports the second coefficient vector to the network device using the second information. Second vector Q(c) p ).

[0327] In some embodiments, according to Examples 1 and 2, the second information includes (or indicates) one of the following:

[0328] Second coefficient vector;

[0329] The non-zero elements in the second coefficient vector;

[0330] The index of the element with the largest modulus in the second coefficient vector.

[0331] Optionally, if the second information contains the second coefficient vector Q(c), then the network device obtains the second coefficient vector Q(c), and the third coefficient vector is the second coefficient vector Q(c).

[0332] Optionally, if the second information contains non-zero elements in the second coefficient vector Q(c), then the network device obtains the second coefficient vector Q(c) based on the non-zero elements, and the third coefficient vector is the second coefficient vector Q(c).

[0333] Optionally, if the L wavenumber domain coordinates in the wavenumber domain coordinate list are arranged in descending order of the power corresponding to each wavenumber domain coordinate, then there may be a situation where the last 0 < L < L elements in the second coefficient vector Q(c) are zero, that is... in, The terminal reports the non-zero part of the second coefficient vector Q(c). That is, the first L-L0 elements in the second coefficient vector Q(c). If the second information contains a non-zero portion... Then the network device is based on the non-zero part Obtain the second coefficient vector Q(c).

[0334] Optionally, if the second information contains the index corresponding to the element with the largest modulus in the second coefficient vector Q(c), i.e., an index, then the network device determines the sparse vector corresponding to the second coefficient vector Q(c) based on this index, and the third coefficient vector is the sparse vector corresponding to the second coefficient vector Q(c). The third coefficient vector is a sparse vector with one non-zero element. Specifically, the element corresponding to the index in the sparse vector is 1, and all other elements are 0.

[0335] In the above embodiments, the second information may only report the non-zero elements in the second coefficient vector, or only report the index corresponding to the element with the largest modulus in the second coefficient vector. Compared with reporting all elements in the second coefficient vector, the feedback overhead of the second information can be reduced.

[0336] In some embodiments, according to embodiment 3, the second information includes (or indicates) a second vector, and one of the following:

[0337] Second coefficient vector;

[0338] The non-zero elements in the second coefficient vector;

[0339] The index of the element with the largest modulus in the second coefficient vector.

[0340] Optionally, if the second information contains the second vector Q(c) p Then the network device obtains the second vector Q(c). p ).

[0341] Optionally, if the second information contains a second coefficient vector Then the network device obtains the second coefficient vector. The third coefficient vector is the second coefficient vector.

[0342] Optionally, if the second information contains a second coefficient vector If the non-zero elements are in the vector, then the network device obtains the second coefficient vector based on the non-zero elements. The third coefficient vector is the second coefficient vector.

[0343] Optionally, if the L wavenumber domain coordinates in the wavenumber domain coordinate list are arranged in descending order according to the power corresponding to each wavenumber domain coordinate, then a second coefficient vector may exist. The last 0 < L0 < L elements in the array are zero, that is... in, Terminal reports second coefficient vector The non-zero part That is, the second coefficient vector The first L-L0 elements in the array. If the second information contains a non-zero portion. Then the network device is based on the non-zero part Obtain the second coefficient vector

[0344] Optionally, if the second information contains a second coefficient vector The index corresponding to the element with the largest modulus value in the vector is used to determine the second coefficient vector by the network device. The corresponding sparse vector, the third coefficient vector is the second coefficient vector The corresponding sparse vector. The third coefficient vector is a sparse vector with one non-zero element. Specifically, the element at the corresponding index in the sparse vector is 1, and all other elements are 0.

[0345] In the above embodiments, the second information may only report the non-zero elements in the second coefficient vector, or only report the index corresponding to the element with the largest modulus in the second coefficient vector. Compared with reporting all elements in the second coefficient vector, the feedback overhead of the second information can be reduced.

[0346] Furthermore, for the antenna array of the network device to be a dual-polarization array, according to embodiment 3, it is only necessary to report a coefficient vector corresponding to both polarization directions and a polarization coefficient of the data layer. Compared with embodiment 2, it is not necessary to report the coefficient vector corresponding to each polarization direction separately. Therefore, the feedback overhead of the second information can be reduced.

[0347] Optionally, the network device receives the second information sent by the terminal and determines the third coefficient vector based on the second information. Optionally, the third coefficient vector is the second coefficient vector or the sparse vector corresponding to the second coefficient vector.

[0348] In some embodiments, the transmission of the second information can be accomplished by at least one of PUCCH, PUSCH, PSCCH, and PSSCH.

[0349] Step S2206: The network device determines the spatial orthogonal basis based on L wavenumber domain coordinates.

[0350] In some embodiments, the network device configures L wavenumber domain coordinates for the terminal. The terminal determines a spatial orthogonal basis B based on the L wavenumber domain coordinates. Similarly, the network device determines the spatial orthogonal basis B based on the L wavenumber domain coordinates. The spatial orthogonal basis B includes L spatial basis vectors, and each of the L spatial basis vectors corresponds one-to-one with one of the L wavenumber domain coordinates. Each column in the spatial orthogonal basis B is a spatial basis vector, and the i-th spatial basis vector in the spatial orthogonal basis B corresponds to the i-th wavenumber domain coordinate among the L wavenumber domain coordinates.

[0351] Optionally, the alternative implementation of the network device determining the spatial orthogonal basis B based on L wavenumber domain coordinates is the same as the alternative implementation of the terminal determining the spatial orthogonal basis B based on L wavenumber domain coordinates. The alternative implementation of step S2206 can be found in the alternative implementation of step S2202 and other related parts of the specification, and will not be repeated here.

[0352] Step S2207: The network device determines the third coefficient vector based on the second information.

[0353] The optional implementations of step S2207 can be found in the optional implementations of step S2205 and other related parts of the specification, and will not be repeated here.

[0354] For ease of description, the third coefficient vector is denoted as...

[0355] Optionally, the network device determines the third coefficient vector based on the second information.

[0356] Optionally, the network device determines the third coefficient vector based on the second information. Let Q(c) be the sparse vector.

[0357] Optionally, the network device determines the second vector Q(c) based on the second information. p ) and the third coefficient vector

[0358] Optionally, the network device determines the second vector Q(c) based on the second information. p ) and the third coefficient vector for The corresponding sparse vector.

[0359] Step S2208: The network device determines the second downlink precoding vector based on the spatial orthogonal basis and the third coefficient vector.

[0360] Network devices are based on the spatial orthogonal basis B and the third coefficient vector. Determine the second downlink precoding vector, denoted as

[0361] Alternatively, if the antenna array of the network device is a one-dimensional single-polarization array, N represents the number of antennas or antenna ports in the antenna array of the network device in one polarization direction.

[0362] Alternatively, if the antenna array of the network device is a one-dimensional dual-polarized array, Second downlink precoding vector The upper half (the first N elements) corresponds to the first polarization direction, and the lower half (the last N elements) corresponds to the second polarization direction.

[0363] Alternatively, if the antenna array of the network device is a two-dimensional single-polarization array, N1 represents the number of antennas or antenna ports in the horizontal direction of the network device's antenna array in one polarization direction, and N2 represents the number of antennas or antenna ports in the vertical direction of the network device's antenna array in one polarization direction.

[0364] Optionally, if the antenna array of the network device is a two-dimensional dual-polarized array, Second downlink precoding vector The upper half (the first N1N2 elements) corresponds to the first polarization direction, and the lower half (the last N1N2 elements) corresponds to the second polarization direction.

[0365] In some embodiments, according to Example 1, if the antenna array of the network device is a single-polarization array (such as a one-dimensional or two-dimensional single-polarization array), then

[0366] Optionally, according to Embodiment 1, the third coefficient vector

[0367] Optionally, according to Embodiment 1, the third coefficient vector Let Q(c) be the sparse vector.

[0368] In some embodiments, according to embodiment 2, if the antenna array of the network device is a dual-polarized array (such as a one-dimensional or two-dimensional dual-polarized array), then

[0369] Optionally, according to Embodiment 2, the third coefficient vector

[0370] Optionally, according to Embodiment 2, the third coefficient vector Let Q(c) be the sparse vector.

[0371] Optionally, according to embodiment 3, if the antenna array of the network device is a dual-polarized array (such as a one-dimensional or two-dimensional dual-polarized array), then Q(c p ) is the second vector.

[0372] Optionally, according to Embodiment 3, the third coefficient vector It is determined by the projection coefficients of the sub-vectors corresponding to the first polarization direction and the sub-vectors corresponding to the second polarization direction in the first downlink precoding vector V, which are projected onto the spatial orthogonal basis.

[0373] Optionally, according to Embodiment 3, the third coefficient vector for The corresponding sparse vector.

[0374] In some embodiments, the network device performs downlink scheduling and / or data transmission based on a second downlink precoding vector.

[0375] In the above embodiments, a unified codebook design scheme in the wavenumber domain is proposed. Compared with the existing Type 2 codebook scheme, the embodiments of this disclosure calculate the spatial orthogonal basis by configuring the wavenumber domain coordinates of the network device, thereby providing more accurate spatial CSI and higher spectral efficiency, and also greatly reducing feedback overhead.

[0376] The communication method involved in the embodiments of this disclosure may include at least one of steps S2201 to S2208. For example, step S2201 may be implemented as an independent embodiment, step S2201 + step S2202 may be implemented as an independent embodiment, step S2203 may be implemented as an independent embodiment, step S2205 may be implemented as an independent embodiment, step S2201 + step S2202 + step S2203 may be implemented as an independent embodiment, step S2201 + step S2202 + step S2203 + step S2204 + step S2205 may be implemented as an independent embodiment, step S2206 may be implemented as an independent embodiment, step S2207 may be implemented as an independent embodiment, step S2205 + S2207 may be implemented as an independent embodiment, and step S2205 + step S2206 + step S2207 + step S2208 may be implemented as an independent embodiment, but is not limited thereto.

[0377] In some embodiments, steps S2201 to S2207 may be performed in an alternate order or simultaneously.

[0378] In some embodiments, steps S2203 to S2208 are optional, and one or more of these steps may be omitted or substituted in different embodiments.

[0379] In some embodiments, steps S2201 to S2205 and steps S2207 to S2208 are optional, and one or more of these steps may be omitted or substituted in different embodiments.

[0380] In some embodiments, steps S2206 to S2208 are optional, and one or more of these steps may be omitted or substituted in different embodiments.

[0381] In some embodiments, steps S2201 to S2204 are optional, and one or more of these steps may be omitted or substituted in different embodiments.

[0382] In some embodiments, the steps and their optional implementations in other embodiments described before or after this embodiment, as well as other related parts in the specification, can be referred to, and will not be repeated here.

[0383] Figure 3 is an interactive schematic diagram of a communication method according to an embodiment of the present disclosure. As shown in Figure 3, the embodiments of the present disclosure relate to a communication method, which includes:

[0384] Step S3101: The network device sends first information to the terminal. The first information is used to indicate L wavenumber domain coordinates.

[0385] The optional implementation of step S3101 can be found in the optional implementation of step S2101 in Figure 2A and other related parts in the specification, which will not be repeated here.

[0386] Optionally, the terminal receives the first information sent by the network device.

[0387] Optionally, the L wavenumber domain coordinates are the L wavenumber domain coordinates with the highest power in the wavenumber domain power distribution of the downlink channel; or, the L wavenumber domain coordinates are the wavenumber domain coordinates with power greater than a threshold in the wavenumber domain power distribution of the downlink channel. Wherein, L is a positive integer.

[0388] Optionally, the method further includes: the terminal sending a second reference signal to the network device. The second reference signal is used by the network device to determine the wavenumber domain power distribution of the downlink channel. For example, the second reference signal is an SRS.

[0389] Optionally, the network device measures the second reference signal transmitted by the terminal to determine the channel matrix of the uplink channel, and determines the wavenumber domain power distribution of the downlink channel based on the uplink channel channel matrix. The network device then determines the aforementioned L wavenumber domain coordinates based on the wavenumber domain power distribution of the downlink channel.

[0390] Optionally, each of the L wavenumber domain coordinates is normalized to the wavenumber domain. Alternatively, each wavenumber domain coordinate can be normalized to the wavenumber domain quantization interval, thereby reducing overhead.

[0391] Step S3102: The terminal determines the spatial orthogonal basis based on the L wavenumber domain coordinates.

[0392] The optional implementation of step S3102 can be found in the optional implementation of step S2102 in Figure 2A and other related parts in the specification, which will not be repeated here.

[0393] Alternatively, if the antenna array of the network device is a one-dimensional array, then the spatial orthogonal basis can be represented as a matrix. Where N represents the number of antennas or antenna ports in one polarization direction of the network device's antenna array. Let κ be the i-th spatial basis vector in a spatial orthogonal basis. i Let r represent the i-th wavenumber domain coordinate among L wavenumber domain coordinates, where r = [r1 r2 … r N ] T r n This represents the coordinates of the nth antenna or antenna port in the antenna array, where n = 1, 2, ..., N.

[0394] Alternatively, if the antenna array of the network device is a two-dimensional array, then the spatial orthogonal basis can be represented as a matrix. Where N1 is the number of antennas or antenna ports in the horizontal direction of the network device's antenna array in one polarization direction, and N2 is the number of antennas or antenna ports in the vertical direction of the network device's antenna array in one polarization direction. Let be the i-th spatial basis vector in a spatial orthogonal basis, (k h,i ,k v,i () represents the i-th wavenumber field coordinate in L wavenumber field coordinates. This represents the coordinates of the antenna or antenna port in the n2th row and n1st column of the antenna array, where n1 = 1, 2, ..., N1 and n2 = 1, 2, ..., N2.

[0395] In the above embodiments, the network device configures the wavenumber domain coordinates of the channel for the terminal. The terminal can calculate the corresponding spatial orthogonal basis based on the wavenumber domain coordinates configured by the network device. Therefore, the network device does not need to configure some candidate spatial orthogonal bases for the terminal, thereby reducing overhead. The saved overhead can be used to quantize the projection coefficients. High-precision quantization coefficients will bring more accurate CSI.

[0396] Optionally, after determining the spatial orthogonal basis, the terminal determines the first coefficient matrix based on the spatial orthogonal basis and the first downlink precoding matrix, quantizes the first coefficient matrix, determines the second coefficient matrix, and then sends second information to the network device. The second information is used by the network device to determine the third coefficient matrix, which is the second coefficient matrix or the sparse matrix corresponding to the second coefficient matrix.

[0397] Optionally, the network device receives the second information sent by the terminal and determines the third coefficient matrix based on the second information.

[0398] Optionally, the network device determines the spatial orthogonal basis based on L wavenumber domain coordinates.

[0399] Optionally, the network device determines the second downlink precoding matrix based on the spatial orthogonal basis and the third coefficient matrix.

[0400] Optionally, if the antenna array of the network device is a single-polarization array (such as a one-dimensional or two-dimensional single-polarization array), the i-th row of the first coefficient matrix represents the projection coefficients of the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis; or, if the antenna array of the network device is a dual-polarization array (such as a one-dimensional or two-dimensional dual-polarization array), the i-th row of the first coefficient matrix represents the projection coefficients of the sub-matrix of the first downlink precoding matrix corresponding to the first polarization direction onto the i-th spatial basis vector in the spatial orthogonal basis, and the L+i-th row represents the projection coefficients of the sub-matrix of the first downlink precoding matrix corresponding to the second polarization direction onto the i-th spatial basis vector in the spatial orthogonal basis; where i is an integer from 1 to L.

[0401] Optionally, the second information may include one of the following:

[0402] Second coefficient matrix;

[0403] Rows in the second coefficient matrix where not all elements are zero;

[0404] The row index corresponding to the element with the largest modulus in each column of the second coefficient matrix.

[0405] Optionally, if the antenna array of the network device is a dual-polarization array, the i-th row of the first coefficient matrix is ​​determined by the projection coefficients of the sub-matrices corresponding to the first polarization direction and the sub-matrices corresponding to the second polarization direction in the first downlink precoding matrix, which are respectively projected onto the i-th spatial basis vector in the spatial orthogonal basis; where i is an integer from 1 to L.

[0406] Optionally, the terminal determines a first vector, quantizes the first vector, and obtains a second vector. The first vector contains inter-polarization coefficients from multiple data layers (r data layers).

[0407] Optionally, the second information includes a second vector and one of the following:

[0408] Second coefficient matrix;

[0409] Rows in the second coefficient matrix where not all elements are zero;

[0410] The row index corresponding to the element with the largest modulus in each column of the second coefficient matrix.

[0411] Optionally, according to the above embodiments, the second downlink precoding matrix is ​​represented as follows: I2 is a 2×2 identity matrix, B is a spatial orthogonal basis, r is the rank, and Q(c p ) is the second vector. This is the third coefficient matrix.

[0412] Optionally, if the second information contains a second coefficient matrix, or rows in the second coefficient matrix where not all elements are zero (non-zero rows), the network device determines the second coefficient matrix based on the second information.

[0413] Optionally, if the second information contains the row index corresponding to the element with the largest modulus in each column of the second coefficient matrix, the network device determines the sparse matrix corresponding to the second coefficient matrix based on the second information. In the sparse matrix, the element at the position corresponding to the row index in each column is 1, and the other elements are 0.

[0414] Optionally, if the second information contains a second vector, the network device determines the second vector based on the second information.

[0415] Optionally, the network device sends a first reference signal to the terminal, the first reference signal being used by the terminal to determine a first downlink precoding matrix. Optionally, the terminal measures the first reference signal sent by the network device to determine the channel matrix of the downlink channel, and determines the first downlink precoding matrix based on the channel matrix of the downlink channel. For example, the first reference signal is CSI-RS.

[0416] Optionally, after determining the spatial orthogonal basis, the terminal determines the first coefficient vector based on the spatial orthogonal basis and the first downlink precoding vector, quantizes the first coefficient vector, determines the second coefficient vector, and then sends the second information to the network device. The second information is used by the network device to determine the third coefficient vector, which is the second coefficient vector or the sparse vector corresponding to the second coefficient vector.

[0417] Optionally, the network device receives the second information sent by the terminal and determines the third coefficient vector based on the second information.

[0418] Optionally, the network device determines the spatial orthogonal basis based on L wavenumber domain coordinates.

[0419] Optionally, the network device determines the second downlink precoding vector based on the spatial orthogonal basis and the third coefficient vector.

[0420] Optionally, if the antenna array of the network device is a single-polarization array, the i-th element in the first coefficient vector represents the projection coefficient of the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis; or, if the antenna array of the network device is a dual-polarization array, the i-th element in the first coefficient vector represents the projection coefficient of the sub-vector of the first downlink precoding vector corresponding to the first polarization direction onto the i-th spatial basis vector in the spatial orthogonal basis, and the L+i-th element represents the projection coefficient of the sub-vector of the first downlink precoding vector corresponding to the second polarization direction onto the i-th spatial basis vector in the spatial orthogonal basis; where i is an integer from 1 to L.

[0421] Optionally, the second information may include one of the following:

[0422] Second coefficient vector;

[0423] Non-zero elements in the second coefficient vector;

[0424] The index of the element with the largest modulus in the second coefficient vector.

[0425] Optionally, if the antenna array of the network device is a dual-polarization array, the i-th element in the first coefficient vector is determined by the projection coefficients of the sub-vectors corresponding to the first polarization direction and the sub-vectors corresponding to the second polarization direction in the first downlink precoding vector, which are respectively projected onto the i-th spatial basis vector in the spatial orthogonal basis; where i is an integer from 1 to L.

[0426] Optionally, the terminal determines a first vector, quantizes the first vector, and obtains a second vector. The first vector contains inter-polarization coefficients of a data layer.

[0427] Optionally, the second information includes a second vector and one of the following:

[0428] Second coefficient vector;

[0429] Non-zero elements in the second coefficient vector;

[0430] The index of the element with the largest modulus in the second coefficient vector.

[0431] Optionally, according to the above embodiments, the second downlink precoding vector is represented as follows: I2 is a 2×2 identity matrix, B is a spatial orthogonal basis, and Q(c p ) is the second vector. This is the third coefficient vector.

[0432] Optionally, if the second information contains a second coefficient vector or a non-zero element in the second coefficient vector, the network device determines the second coefficient vector based on the second information.

[0433] Optionally, if the second information contains the index corresponding to the element with the largest modulus in the second coefficient vector, the network device determines the sparse vector corresponding to the second coefficient vector based on the second information. The element in the sparse vector corresponding to the index is 1, and all other elements are 0.

[0434] Optionally, if the second information contains a second vector, the network device determines the second vector based on the second information.

[0435] Optionally, the network device sends a first reference signal to the terminal, the first reference signal being used by the terminal to determine a first downlink precoding vector. Optionally, the terminal measures the first reference signal sent by the network device to determine the channel matrix of the downlink channel, and determines the first downlink precoding vector based on the channel matrix of the downlink channel. For example, the first reference signal is CSI-RS.

[0436] Through the above embodiments, the network device determines the precoding vector or matrix for downlink transmission.

[0437] In some embodiments, the steps and their optional implementations in other embodiments described before or after this embodiment, as well as other related parts in the specification, can be referred to, and will not be repeated here.

[0438] In some embodiments, this embodiment can be combined with other embodiments. For example, this embodiment can be combined with one or more steps S2103 to S2108 in FIG2A, or this embodiment can be combined with one or more steps S2203 to S2208 in FIG2B.

[0439] Figure 4 is an interactive schematic diagram of a communication method according to an embodiment of the present disclosure. As shown in Figure 4, the embodiments of the present disclosure relate to codebook design in the wavenumber domain, and the above method includes:

[0440] Step S4101: gNB configures a wavenumber domain coordinate list for UE.

[0441] Optionally, the wavenumber domain coordinate list corresponds to all paths (or clusters) or the highest-powered path (or cluster) in the wavenumber domain representation of the channel between the gNB and the UE. For ease of description, the number of wavenumber domain coordinates included in the wavenumber domain coordinate list is L.

[0442] If the gNB-side antenna array is a one-dimensional array, then each element in the wavenumber domain coordinate list is a scalar.

[0443] Optionally, the list of wavenumber domain coordinates can be represented as Where -k0≤k i ≤k0, i=1,2,...,L.

[0444] Optionally, each element (wavenumber domain coordinate) in the list of wavenumber domain coordinates can be normalized to the wavenumber k0, that is, the list can be represented as in,

[0445] Optionally, each element (wavenumber domain coordinate) in the list of wavenumber domain coordinates can be normalized to the quantization interval Δ, that is, the list can be represented as in, or

[0446] Optionally, the value of Δ can be predefined by the protocol or explicitly configured to the UE by the gNB. Optionally, Where A is the aperture of the one-dimensional array on the gNB side.

[0447] If the gNB-side antenna array is a two-dimensional array, then each element in the wavenumber domain coordinate list is a binary tuple.

[0448] Optionally, the list of wavenumber domain coordinates can be represented as in, i = 1, 2, ..., L.

[0449] Optionally, each element (wavenumber domain coordinate) in the list of wavenumber domain coordinates can be normalized to the wavenumber k0, that is, the list can be represented as in,

[0450] Optionally, each element (wavenumber domain coordinate) in the list of wavenumber domain coordinates can be normalized to Δ. h and Δ v In other words, a list can be represented as in, or or

[0451] Optionally, Δ h and Δ v The value can be predefined by the protocol or explicitly configured to the UE by the gNB. Optionally, Where A h and A v These are the horizontal and vertical apertures of the two-dimensional array on the gNB side, respectively.

[0452] Optionally, the gNB configures a list of wavenumber domain coordinates for the UE via configuration signaling.

[0453] Optionally, the gNB configures a list of wavenumber domain coordinates and a wavenumber domain quantization interval Δ for the UE via configuration signaling.

[0454] Optionally, the gNB configures the wavenumber domain coordinate list and the aperture A of the gNB-side one-dimensional array for the UE via configuration signaling.

[0455] Optionally, the gNB configures a list of wavenumber domain coordinates and a wavenumber domain quantization interval for the UE via configuration signaling, including the horizontal quantization interval Δ. hand the quantization interval Δ in the vertical direction v .

[0456] Optionally, the gNB configures the wavenumber domain coordinate list and the aperture of the gNB-side two-dimensional array for the UE via configuration signaling, including the horizontal aperture A. h and vertical aperture A v .

[0457] Optionally, the configuration signaling can be at least one of DCI, MAC CE, and RRC.

[0458] Optionally, the gNB utilizes channel reciprocity to obtain a list of wavenumber domain coordinates.

[0459] Optionally, the gNB measures the SRS transmitted by the UE to obtain the uplink channel, and uses the reciprocity of the uplink and downlink channels to derive the downlink channel, obtaining the power distribution of the downlink channel in the wavenumber domain, determining the wavenumber domain coordinates with higher power (denoted as L), and arranging them into a list. Optionally, the coordinates are arranged in descending order according to the power distribution corresponding to each wavenumber domain coordinate.

[0460] Step S4102: The UE calculates the corresponding spatial orthogonal basis according to the wavenumber domain coordinate list.

[0461] Optionally, the UE receives a list of wavenumber domain coordinates.

[0462] If the gNB-side antenna array is a one-dimensional array, then the spatial orthogonal basis can be represented as a matrix. Where N represents the number of antennas or antenna ports in one polarization direction of the gNB-side antenna array. Let r be the i-th spatial basis vector, i = 1, 2, ..., L. Where r = [r1 r2 ... r...] N ] T This represents the coordinates of each antenna or antenna port in the gNB-side antenna array, i.e., rn is the coordinate of the nth antenna or antenna port, where n = 1, 2, ..., N.

[0463] In particular, for a uniform linear array, r n = (n-1)d, where d is the spacing between adjacent antennas or antenna ports.

[0464] If the gNB-side antenna array is a two-dimensional array, then the spatial orthogonal basis can be represented as a matrix. Where N1 represents the number of antennas or antenna ports in the horizontal direction of the gNB-side antenna array in one polarization direction, and N2 represents the number of antennas or antenna ports in the vertical direction of the gNB-side antenna array in one polarization direction. If the antenna indexing order in the array is column-first, then row-first, then the i-th spatial basis vector can be represented as... Let represent the Kronecker product of two matrices. Represents the coordinates of the antenna or antenna port in the n2th row and n1st column of the gNB-side antenna array (or described as the coordinates of the n1th antenna or antenna port in the horizontal direction and the n2th antenna or antenna port in the vertical direction), where n1 = 1, 2, ..., N1, n2 = 1, 2, ..., N2.

[0465] In particular, for uniform arrays, Where d h d represents the horizontal spacing between adjacent antennas or antenna ports in the gNB-side antenna array. v The spacing between adjacent antennas or antenna ports in the vertical direction of the gNB-side antenna array.

[0466] Step S4103: The UE obtains the spatial channel matrix of the downlink channel by measuring the CSI-RS, and calculates the downlink precoding vector or matrix based on the spatial channel matrix of the downlink channel, denoted as V.

[0467] Step S4104: The UE calculates the corresponding coefficient vector or matrix (denoted as c) based on the spatial orthogonal basis and the downlink precoding vector or matrix, and quantizes the coefficient vector or matrix.

[0468] Step S4105: The UE converts the quantized coefficient vector or matrix (denoted as...) Feedback is sent to gNB.

[0469] The spatial orthogonal basis is obtained through step S4102.

[0470] The downlink precoding vector (or matrix) is obtained through step S4103.

[0471] Optionally, the i-th element in the coefficient vector corresponds to the i-th coordinate in the wavenumber domain coordinate list, and to the i-th spatial basis vector b in the spatial orthogonal basis. i correspond.

[0472] Optionally, the i-th row of the coefficient matrix corresponds to the i-th coordinate in the wavenumber domain coordinate list and to the i-th spatial basis vector in the spatial orthogonal basis.

[0473] Optionally, the i-th element and the L+i-th element in the coefficient vector correspond to the i-th coordinate in the wavenumber domain coordinate list and the i-th spatial basis vector in the spatial orthogonal basis.

[0474] Optionally, the i-th row and L+i-th row of the coefficient matrix correspond to the i-th coordinate in the wavenumber domain coordinate list and the i-th spatial basis vector in the spatial orthogonal basis.

[0475] Where Q(·) is the quantization function, which can represent uniform quantization or non-uniform quantization; it can represent absolute quantization or relative quantization.

[0476] Alternatively, if the antenna array on the gNB side is a single-polarization array, then in, It refers to rank.

[0477] Optionally, when the quantized coefficient vector or matrix When the last 0 < L < L is zero, that is... in, UE can report only the non-zero part This can reduce feedback overhead.

[0478] Optionally, for The UE can report only the row number (or row index or row number) of the element with the largest modulus in each column (corresponding to each layer), for a total of r row indices (or row numbers), thereby reducing feedback overhead.

[0479] Optionally, if the antenna array on the gNB side is a dual-polarized array, then Where I2 is a 2×2 identity matrix.

[0480] Optionally, if the antenna array on the gNB side is a dual-polarization array, then the two polarization directions can correspond to the same coefficient vector or matrix, that is... in The vector or matrix of coefficients corresponding to both polarization directions. represents the polarization coefficients between each layer, and ⊙ represents the Khatri-Rao product of the two matrices. Optionally, the UE will... and c p After quantization of a total of (L+1)r coefficients (i.e.) and Q(c p Report to gNB.

[0481] Optionally, for The UE can report only the row number (or row index or row number) of the element with the largest modulus in each column (corresponding to each layer), for a total of r row indices (or row numbers). Therefore, the UE reports a total of r row indices (corresponding to each layer). ) and r inter-polarity coefficients (corresponding to c p ).

[0482] Optionally, the above feedback can be accomplished using at least one of PUCCH, PUSCH, PSCCH, and PSSCH.

[0483] Step S4106: gNB calculates the corresponding spatial orthogonal basis based on the wavenumber domain coordinate list.

[0484] For an alternative implementation of step S4106, please refer to step S4102.

[0485] Step S4107: gNB calculates the downlink precoding vector or matrix based on the spatial orthogonal basis and the quantized coefficient vector or matrix, denoted as...

[0486] Optionally, if the antenna array on the gNB side is a single-polarization array, then

[0487] Optionally, for coefficient vectors or matrices If the UE reports the row index, then It is a sparse matrix. Assume the row index of the l-th layer is k. l ,So Only the kth column is in the lth column l The kth (i.e., the kth) l The element in the l-th row is 1, and all other elements in the l-th column are 0; 1 ≤ l ≤ r, 1 ≤ k l ≤L.

[0488] Optionally, if the antenna array on the gNB side is a dual-polarized array, then

[0489] Optionally, if the two polarization directions correspond to the same coefficient vector or matrix, the downlink precoding vector (or matrix) can be determined as follows:

[0490] Optionally, for If the UE reports r row indexes, then It is a sparse matrix. Assume the row index of the l-th layer is k. l ,So Only the kth column is in the lth column l The kth (i.e., the kth) l The element in the l-th row is 1, and all other elements in the l-th column are 0; 1 ≤ l ≤ r, 1 ≤ k l ≤L.

[0491] Optionally, gNB with As a spatial CSI, it performs downlink scheduling and data transmission.

[0492] Optionally, steps S4101 to S4106 can be performed in an alternate order or simultaneously.

[0493] This disclosure proposes a unified codebook design scheme in the wavenumber domain. Compared with the existing Type 2 codebook scheme, the codebook design scheme proposed in this disclosure can not only provide more accurate spatial CSI and higher spectral efficiency, but also greatly reduce feedback overhead.

[0494] In some embodiments, the steps and their optional implementations in other embodiments described before or after this embodiment, as well as other related parts in the specification, can be referred to, and will not be repeated here.

[0495] This disclosure also proposes an apparatus (also referred to as a communication device, etc.) for implementing any of the above methods. For example, an apparatus is proposed that includes units or modules for implementing the steps performed by the terminal in any of the above methods. Furthermore, another apparatus is proposed that includes units or modules for implementing the steps performed by a network device (e.g., an access network device, a core network functional node, a core network device, etc.) in any of the above methods.

[0496] It should be understood that the division of units or modules in the above device is only a logical functional division. In actual implementation, they can be fully or partially integrated into a single physical entity, or they can be physically separated. Furthermore, the units or modules in the device can be implemented by a processor calling software: for example, the device includes a processor connected to a memory containing instructions. The processor calls the instructions stored in the memory to implement any of the above methods or to implement the functions of the units or modules in the above device. The processor can be, for example, a general-purpose processor, such as a Central Processing Unit (CPU) or a microprocessor, and the memory can be internal or external to the device. Alternatively, the units or modules in the device can be implemented in the form of hardware circuits. The functionality of some or all of the units or modules can be achieved through the design of these hardware circuits, which can be understood as one or more processors. For example, in one implementation, the hardware circuit is an application-specific integrated circuit (ASIC). The functionality of some or all of the units or modules is achieved through the design of the logical relationships between the components within the circuit. In another implementation, the hardware circuit can be implemented using a programmable logic device (PLD). Taking a field-programmable gate array (FPGA) as an example, it can include a large number of logic gates. The connection relationships between the logic gates are configured through configuration files, thereby achieving the functionality of some or all of the units or modules. All units or modules of the above device can be implemented entirely through processor-called software, entirely through hardware circuits, or partially through processor-called software with the remaining parts implemented through hardware circuits.

[0497] In this embodiment, the processor is a circuit with signal processing capabilities. In one implementation, the processor can be a circuit with instruction read and execute capabilities, such as a Central Processing Unit (CPU), a microprocessor, a graphics processing unit (GPU) (which can be understood as a microprocessor), or a digital signal processor (DSP). In another implementation, the processor can implement certain functions through the logical relationships of hardware circuits. The logical relationships of the aforementioned hardware circuits are fixed or reconfigurable. For example, the processor is a hardware circuit implemented using an application-specific integrated circuit (ASIC) or a programmable logic device (PLD), such as an FPGA. In a reconfigurable hardware circuit, the process of the processor loading a configuration document and configuring the hardware circuit can be understood as the process of the processor loading instructions to implement the functions of some or all of the above units or modules. Furthermore, it can also be a hardware circuit designed for artificial intelligence, which can be understood as an ASIC, such as a Neural Network Processing Unit (NPU), a Tensor Processing Unit (TPU), or a Deep Learning Processing Unit (DPU).

[0498] Figure 5A is a schematic diagram of the terminal structure proposed in an embodiment of this disclosure. Terminal 5100 is used to execute any of the above methods. In some embodiments, as shown in Figure 5A, terminal 5100 may include at least one of a transceiver module 5101, a processing module 5102, etc. In some embodiments, the transceiver module is used to receive first information sent by a network device, the first information indicating L wavenumber domain coordinates. The processing module is used to determine a spatial orthogonal basis based on the L wavenumber domain coordinates, the spatial orthogonal basis including L spatial basis vectors, the L spatial basis vectors corresponding one-to-one with the L wavenumber domain coordinates. Optionally, the transceiver module is used to execute at least one of the communication steps (e.g., steps S2101, S2105, S2201, S2205, but not limited thereto) performed by the terminal in any of the above methods, which will not be elaborated further here. Optionally, the above processing module is used to execute at least one of the other steps executed by the terminal in any of the above methods (e.g., steps 2102, S2103, S2104, S2202, S2203, S2204, but not limited thereto), which will not be elaborated here.

[0499] Figure 5B is a schematic diagram of the structure of a network device proposed in an embodiment of this disclosure. The network device 5200 is used to execute any of the above methods. In some embodiments, as shown in Figure 5B, the network device 5200 may include at least one of a transceiver module 5201, a processing module 5202, etc. In some embodiments, the transceiver module is used to send first information to a terminal, the first information indicating L wavenumber domain coordinates, where L is a positive integer, the L wavenumber domain coordinates being used to determine a spatial orthogonal basis, the spatial orthogonal basis including L spatial basis vectors, the L spatial basis vectors corresponding one-to-one with the L wavenumber domain coordinates. Optionally, the transceiver module is used to execute at least one of the communication steps (e.g., steps S2101, S2105, S2201, S2205, but not limited thereto) performed by the network device in any of the above methods, which will not be elaborated further here. Optionally, the above processing module is used to execute at least one of the other steps executed by the network device in any of the above methods (e.g., steps S2106, S2107, S2108, S2206, S2207, S2208, but not limited thereto), which will not be elaborated here.

[0500] In some embodiments, the transceiver module may include a transmitting module and / or a receiving module, which may be separate or integrated. Optionally, the transceiver module may be interchangeable with a transceiver.

[0501] In some embodiments, the processing module may be a single module or may include multiple sub-modules. Optionally, the multiple sub-modules may each perform all or part of the steps required by the processing module.

[0502] In some embodiments, the processing module can be replaced by the processor, and the transceiver module can be replaced by the transceiver.

[0503] Figure 6A is a schematic diagram of the structure of the communication device 6100 proposed in an embodiment of this disclosure. The communication device 6100 can be a network device (e.g., access network device, core network device, etc.), a terminal (e.g., user equipment, etc.), a chip, chip system, or processor that supports the network device in implementing any of the above methods, or a chip, chip system, or processor that supports the terminal in implementing any of the above methods. The communication device 6100 can be used to implement the methods described in the above method embodiments; for details, please refer to the descriptions in the above method embodiments.

[0504] As shown in Figure 6A, the communication device 6100 is used to execute any of the above methods. In some embodiments, the communication device 6100 includes one or more processors 6101. The processor 6101 may be a general-purpose processor or a special-purpose processor, such as a baseband processor or a central processing unit. The baseband processor may be used to process communication protocols and communication data, and the central processing unit may be used to control communication devices (e.g., base stations, baseband chips, terminal devices, terminal device chips, DUs or CUs, etc.), execute programs, and process program data. Optionally, the communication device 6100 is used to execute any of the above methods. Optionally, one or more processors 6101 are used to invoke instructions to cause the communication device 6100 to execute any of the above methods.

[0505] In some embodiments, the communication device 6100 further includes one or more transceivers 6102. When the communication device 6100 includes one or more transceivers 6102, the transceiver 6102 performs at least one of the communication steps such as sending and / or receiving in the above method (e.g., steps S2101, S2105, S2201, S2205, but not limited thereto), and the processor 6101 performs at least one of other steps (e.g., steps S2102, S2103, S2104, S2106, S2107, S2108, S2202, S2203, S2204, S2206, S2207, S2208, but not limited thereto). In optional embodiments, the transceiver may include a receiver and / or a transmitter, which may be separate or integrated together. Optionally, terms such as transceiver, transceiver unit, transceiver, transceiver circuit, interface circuit, and interface can be used interchangeably; terms such as transmitter, transmitter unit, transmitter, and transmitter circuit can be used interchangeably; and terms such as receiver, receiver unit, receiver, and receiver circuit can be used interchangeably.

[0506] In some embodiments, the communication device 6100 further includes one or more memories 6103 for storing data and / or instructions. Optionally, one or more processors 6101 are used to invoke instructions stored in the memory 6103 to cause the communication device 6100 to perform any of the above methods. Optionally, all or part of the memory 6103 may also be located outside the communication device 6100. In an optional embodiment, the communication device 6100 may include one or more interface circuits 6104. Optionally, the interface circuit 6104 is connected to the memory 6103 and can be used to receive data and / or instructions from the memory 6103 or other devices, and can be used to send data and / or instructions to the memory 6103 or other devices. For example, the interface circuit 6104 can read data and / or instructions stored in the memory 6103 and send the data and / or instructions to the processor 6101.

[0507] The communication device 6100 described in the above embodiments may be a network device or a terminal, but the scope of the communication device 6100 described in this disclosure is not limited thereto, and the structure of the communication device 6100 may not be limited by FIG. 6A. The communication device may be a standalone device or a part of a larger device. For example, the communication device may be: (1) a standalone integrated circuit IC, or chip, or chip system or subsystem; (2) a collection of one or more ICs, optionally, the IC collection may also include storage components for storing data, programs and / or instructions; (3) an ASIC, such as a modem; (4) a module that can be embedded in other devices; (5) a receiver, terminal device, smart terminal device, cellular phone, wireless device, handheld device, mobile unit, vehicle device, network device, cloud device, artificial intelligence device, etc.; (6) others, etc.

[0508] Figure 6B is a schematic diagram of the structure of chip 6200 according to an embodiment of this disclosure. For cases where the communication device 6100 can be a chip or a chip system, please refer to the schematic diagram of chip 6200 shown in Figure 6B, but it is not limited thereto.

[0509] Chip 6200 includes one or more processors 6201. Chip 6200 is used to perform any of the methods described above.

[0510] In some embodiments, chip 6200 further includes one or more interface circuits 6202. Optionally, terms such as interface circuit, interface, and transceiver pin can be used interchangeably. In some embodiments, chip 6200 further includes one or more memories 6203 for storing data and / or instructions. Optionally, all or part of the memories 6203 may be located outside of chip 6200. Optionally, interface circuit 6202 is connected to memory 6203, and interface circuit 6202 can be used to receive data and / or instructions from memory 6203 or other devices, and interface circuit 6202 can be used to send data and / or instructions to memory 6203 or other devices. For example, interface circuit 6202 can read data and / or instructions stored in memory 6203 and send the data and / or instructions to processor 6201.

[0511] In some embodiments, the interface circuit 6202 performs at least one of the communication steps such as sending and / or receiving in the above method (e.g., steps S2101, S2105, S2201, S2205, but not limited thereto). The interface circuit 6202 performing the communication steps such as sending and / or receiving in the above method refers, for example, to the interface circuit 6202 performing data and / or instruction interaction between the processor 6201, the chip 6200, the memory 6203, or the transceiver device. In some embodiments, the processor 6201 performs at least one of other steps (e.g., steps S2102, S2103, S2104, S2106, S2107, S2108, S2202, S2203, S2204, S2206, S2207, S2208, but not limited thereto).

[0512] The modules and / or devices described in the various embodiments, such as virtual devices, physical devices, and chips, can be combined or separated arbitrarily as needed. Optionally, some or all steps can also be performed collaboratively by multiple modules and / or devices, which is not limited here.

[0513] This disclosure also proposes a storage medium storing instructions that, when executed on a communication device, cause the communication device to perform any of the above methods. Optionally, the storage medium is an electronic storage medium. Optionally, the storage medium is a computer-readable storage medium, but not limited thereto; it may also be a storage medium readable by other devices. Optionally, the storage medium may be a non-transitory storage medium, but not limited thereto; it may also be a temporary storage medium.

[0514] This disclosure also proposes a program product, including a program and / or instructions, which, when executed by a communication device, cause the communication device to perform any of the above methods. Optionally, the program product is a computer program product. Optionally, the program product is stored on the storage medium.

[0515] This disclosure also proposes a computer program that, when run on a computer, causes the computer to perform any of the above methods.

Claims

1. A communication method, characterized in that, The method, executed by a terminal, includes: Receive first information sent by the network device, the first information being used to indicate L wavenumber domain coordinates, where L is a positive integer; Based on the L wavenumber domain coordinates, a spatial orthogonal basis is determined. The spatial orthogonal basis includes L spatial basis vectors, and the L spatial basis vectors correspond one-to-one with the L wavenumber domain coordinates.

2. The method according to claim 1, characterized in that, The method further includes: Based on the spatial orthogonal basis and the first downlink precoding matrix or the first downlink precoding vector, determine the first coefficient matrix or the first coefficient vector; Quantize the first coefficient matrix or the first coefficient vector to determine the second coefficient matrix or the second coefficient vector; Send second information to the network device, the second information being used by the network device to determine a third coefficient matrix or a third coefficient vector, the third coefficient matrix being the second coefficient matrix or a sparse matrix corresponding to the second coefficient matrix, and the third coefficient vector being the second coefficient vector or a sparse vector corresponding to the second coefficient vector.

3. The method according to claim 2, characterized in that, The antenna array of the network device is a single-polarization array. The i-th row of the first coefficient matrix represents the projection coefficients of the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis; or, the i-th element of the first coefficient vector represents the projection coefficients of the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis. The antenna array is a dual-polarization array. The i-th row of the first coefficient matrix represents the projection coefficients of the sub-matrix corresponding to the first polarization direction in the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis. The L+i-th row represents the projection coefficients of the sub-matrix corresponding to the second polarization direction in the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis. Alternatively, the i-th element of the first coefficient vector represents the projection coefficient of the sub-vector corresponding to the first polarization direction in the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis, and the L+i-th element represents the projection coefficient of the sub-vector corresponding to the second polarization direction in the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis. The antenna array is a dual-polarization array. The i-th row of the first coefficient matrix is ​​determined by the projection coefficients of the sub-matrices corresponding to the first polarization direction and the sub-matrices corresponding to the second polarization direction in the first downlink precoding matrix, which are respectively projected onto the i-th spatial basis vector in the spatial orthogonal basis. Alternatively, the i-th element of the first coefficient vector is determined by the projection coefficients of the sub-vectors corresponding to the first polarization direction and the sub-vectors corresponding to the second polarization direction in the first downlink precoding vector, which are respectively projected onto the i-th spatial basis vector in the spatial orthogonal basis. Where i is an integer from 1 to L.

4. The method according to claim 2 or 3, characterized in that, The second information includes one of the following: The second coefficient matrix; The second coefficient vector; The rows in the second coefficient matrix where not all elements are zero; The non-zero elements in the second coefficient vector; The row index corresponding to the element with the largest modulus in each column of the second coefficient matrix; The index of the element with the largest modulus in the second coefficient vector; Wherein, the antenna array of the network device is a single-polarization array, and the i-th row of the first coefficient matrix represents the projection coefficients of the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis; or, the i-th element of the first coefficient vector represents the projection coefficients of the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis. Alternatively, the antenna array is a dual-polarization array, and the i-th row of the first coefficient matrix represents the projection coefficients of the submatrix corresponding to the first polarization direction of the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis. The projection coefficients on the spatial basis vectors, the L+ith row represents the projection coefficients of the sub-matrix in the first downlink precoding matrix corresponding to the second polarization direction projected onto the i-th spatial basis vector in the spatial orthogonal basis, or, the i-th element in the first coefficient vector represents the projection coefficients of the sub-vector in the first downlink precoding vector corresponding to the first polarization direction projected onto the i-th spatial basis vector in the spatial orthogonal basis, and the L+ith element represents the projection coefficients of the sub-vector in the first downlink precoding vector corresponding to the second polarization direction projected onto the i-th spatial basis vector in the spatial orthogonal basis; or, The second information includes a second vector and one of the following: The second coefficient matrix; The second coefficient vector; The rows in the second coefficient matrix where not all elements are zero; The non-zero elements in the second coefficient vector; The row index corresponding to the element with the largest modulus in each column of the second coefficient matrix; The index of the element with the largest modulus in the second coefficient vector; Wherein, the second vector is a quantized vector of the first vector, the first vector contains one or more inter-polarization coefficients of the data layer, the antenna array is a dual-polarization array, the i-th row of the first coefficient matrix is ​​determined by the projection coefficients of the sub-matrices of the first downlink precoding matrix corresponding to the first polarization direction and the sub-matrices corresponding to the second polarization direction projected onto the i-th spatial basis vector in the spatial orthogonal basis, or the i-th element of the first coefficient vector is determined by the projection coefficients of the sub-vectors of the first downlink precoding vector corresponding to the first polarization direction and the sub-vectors corresponding to the second polarization direction projected onto the i-th spatial basis vector in the spatial orthogonal basis.

5. The method according to any one of claims 2-4, characterized in that, The method further includes: Measure the first reference signal transmitted by the network device to determine the channel matrix of the downlink channel; The first downlink precoding matrix or the first downlink precoding vector is determined based on the channel matrix of the downlink channel.

6. The method according to any one of claims 1-5, characterized in that, The L wavenumber domain coordinates are the L wavenumber domain coordinates with the highest power in the wavenumber domain power distribution of the downlink channel; or, the L wavenumber domain coordinates are the wavenumber domain coordinates with power greater than a threshold in the wavenumber domain power distribution of the downlink channel.

7. The method according to claim 6, characterized in that, The method further includes: A second reference signal is sent to the network device, the second reference signal being used by the network device to determine the wavenumber domain power distribution of the downlink channel.

8. The method according to any one of claims 1-7, characterized in that, Each of the wavenumber domain coordinates is normalized to the wavenumber. λ is the wavelength; or, each of the wavenumber domain coordinates is normalized to the wavenumber domain quantization interval.

9. The method according to any one of claims 1-8, characterized in that, The antenna array of the network device is a one-dimensional array, and the spatial orthogonal basis is represented as follows: Where N is the number of antennas or antenna ports in the antenna array in one polarization direction. Let κ be the i-th spatial basis vector in the spatial orthogonal basis. i This represents the i-th wavenumber domain coordinate among the L wavenumber domain coordinates, where r = [r1 r2 ... r...]. N ] T r n This represents the coordinates of the nth antenna or antenna port in the antenna array, where n = 1, 2, ..., N; or, The antenna array of the network device is a two-dimensional array, and the spatial orthogonal basis is represented as follows: Wherein, N1 is the number of antennas or antenna ports in the horizontal direction of the antenna array in one polarization direction, and N2 is the number of antennas or antenna ports in the vertical direction of the antenna array in one polarization direction. Let be the i-th spatial basis vector in the spatial orthogonal basis, (κ) h,i ,κ v,i () represents the i-th wavenumber domain coordinate among the L wavenumber domain coordinates. The coordinates of the antenna or antenna port in the n2th row and n1th column of the antenna array are given, where n1 = 1, 2, ..., N1 and n2 = 1, 2, ..., N2.

10. A communication method, characterized in that, Performed by a network device, the method includes: Send first information to the terminal. The first information is used to indicate L wavenumber domain coordinates, where L is a positive integer. The L wavenumber domain coordinates are used to determine a spatial orthogonal basis. The spatial orthogonal basis includes L spatial basis vectors, and the L spatial basis vectors correspond one-to-one with the L wavenumber domain coordinates.

11. The method according to claim 10, characterized in that, The method further includes: Receive the second information sent by the terminal; A third coefficient matrix or a third coefficient vector is determined based on the second information. The third coefficient matrix is ​​the second coefficient matrix or a sparse matrix corresponding to the second coefficient matrix. The third coefficient vector is the second coefficient vector or a sparse vector corresponding to the second coefficient vector. The second coefficient matrix is ​​a matrix obtained by quantizing the first coefficient matrix. The first coefficient matrix is ​​determined by the terminal based on the spatial orthogonal basis and the first downlink precoding matrix. The second coefficient vector is a vector obtained by quantizing the first coefficient vector. The first coefficient vector is determined by the terminal based on the spatial orthogonal basis and the first downlink precoding vector. The second downlink precoding matrix or the second downlink precoding vector is determined based on the spatial orthogonal basis and the third coefficient matrix or the third coefficient vector.

12. The method according to claim 11, characterized in that, The antenna array of the network device is a single-polarization array. The i-th row of the first coefficient matrix represents the projection coefficients of the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis; or, the i-th element of the first coefficient vector represents the projection coefficients of the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis. The antenna array is a dual-polarization array. The i-th row of the first coefficient matrix represents the projection coefficients of the sub-matrix corresponding to the first polarization direction in the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis. The L+i-th row represents the projection coefficients of the sub-matrix corresponding to the second polarization direction in the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis. Alternatively, the i-th element of the first coefficient vector represents the projection coefficient of the sub-vector corresponding to the first polarization direction in the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis, and the L+i-th element represents the projection coefficient of the sub-vector corresponding to the second polarization direction in the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis. The antenna array is a dual-polarization array. The i-th row of the first coefficient matrix is ​​determined by the projection coefficients of the sub-matrices corresponding to the first polarization direction and the sub-matrices corresponding to the second polarization direction in the first downlink precoding matrix, which are respectively projected onto the i-th spatial basis vector in the spatial orthogonal basis. Alternatively, the i-th element of the first coefficient vector is determined by the projection coefficients of the sub-vectors corresponding to the first polarization direction and the sub-vectors corresponding to the second polarization direction in the first downlink precoding vector, which are respectively projected onto the i-th spatial basis vector in the spatial orthogonal basis. Where i is an integer from 1 to L.

13. The method according to claim 11 or 12, characterized in that, The second information includes one of the following: The second coefficient matrix; The second coefficient vector; The rows in the second coefficient matrix where not all elements are zero; The non-zero elements in the second coefficient vector; The row index corresponding to the element with the largest modulus in each column of the second coefficient matrix; The index of the element with the largest modulus in the second coefficient vector; Wherein, the antenna array of the network device is a single-polarization array, and the i-th row of the first coefficient matrix represents the projection coefficients of the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis; or, the i-th element of the first coefficient vector represents the projection coefficients of the first downlink precoding vector onto the i-th spatial basis vector in the spatial orthogonal basis. Alternatively, the antenna array is a dual-polarization array, and the i-th row of the first coefficient matrix represents the projection coefficients of the submatrix corresponding to the first polarization direction of the first downlink precoding matrix onto the i-th spatial basis vector in the spatial orthogonal basis. The projection coefficients on the spatial basis vectors, the L+ith row represents the projection coefficients of the sub-matrix in the first downlink precoding matrix corresponding to the second polarization direction projected onto the i-th spatial basis vector in the spatial orthogonal basis, or, the i-th element in the first coefficient vector represents the projection coefficients of the sub-vector in the first downlink precoding vector corresponding to the first polarization direction projected onto the i-th spatial basis vector in the spatial orthogonal basis, and the L+ith element represents the projection coefficients of the sub-vector in the first downlink precoding vector corresponding to the second polarization direction projected onto the i-th spatial basis vector in the spatial orthogonal basis; or, The second information includes a second vector and one of the following: The second coefficient matrix; The second coefficient vector; The rows in the second coefficient matrix where not all elements are zero; The non-zero elements in the second coefficient vector; The row index corresponding to the element with the largest modulus in each column of the second coefficient matrix; The index of the element with the largest modulus in the second coefficient vector; Wherein, the second vector is a quantized vector of the first vector, the first vector contains one or more inter-polarization coefficients of the data layer, the antenna array is a dual-polarization array, the i-th row of the first coefficient matrix is ​​determined by the projection coefficients of the sub-matrices of the first downlink precoding matrix corresponding to the first polarization direction and the sub-matrices corresponding to the second polarization direction projected onto the i-th spatial basis vector in the spatial orthogonal basis, or the i-th element of the first coefficient vector is determined by the projection coefficients of the sub-vectors of the first downlink precoding vector corresponding to the first polarization direction and the sub-vectors corresponding to the second polarization direction projected onto the i-th spatial basis vector in the spatial orthogonal basis.

14. The method according to claim 13, characterized in that, The second downlink precoding matrix is ​​represented as follows I2 is a 2×2 identity matrix, B is the spatial orthogonal basis, r is the rank, and Q(c p ) is the second vector, The third coefficient matrix, ⊙ represents the Kronecker product operation, and ⊙ represents the Khatri-Rao product operation; or, The second downlink precoding vector is represented as I2 is a 2×2 identity matrix, B is the spatial orthogonal basis, and Q(c p ) is the second vector, This is the third coefficient vector.

15. The method according to claim 13 or 14, characterized in that, When the second information contains the row index corresponding to the element with the largest modulus in each column of the second coefficient matrix, the third coefficient matrix is ​​a sparse matrix corresponding to the second coefficient matrix, and the element corresponding to the row index in each column of the sparse matrix is ​​1, and the other elements are 0; or, If the second information contains the index corresponding to the element with the largest modulus in the second coefficient vector, the third coefficient vector is a sparse vector corresponding to the second coefficient vector, where the element at the index position in the sparse vector is 1, and all other elements are 0.

16. The method according to any one of claims 11-15, characterized in that, The method further includes: A first reference signal is sent to the terminal, the first reference signal being used by the terminal to determine the first downlink precoding matrix or the first downlink precoding vector.

17. The method according to any one of claims 10-16, characterized in that, The L wavenumber domain coordinates are the L wavenumber domain coordinates with the highest power in the wavenumber domain power distribution of the downlink channel; or, the L wavenumber domain coordinates are the wavenumber domain coordinates with power greater than a threshold in the wavenumber domain power distribution of the downlink channel.

18. The method according to claim 17, characterized in that, The method further includes: The channel matrix of the uplink channel is determined by measuring the second reference signal sent by the terminal. Based on the channel matrix of the uplink channel, the wavenumber domain power distribution of the downlink channel is determined.

19. The method according to any one of claims 10-18, characterized in that, Each of the wavenumber domain coordinates is normalized to the wavenumber. λ is the wavelength; or, each of the wavenumber domain coordinates is normalized to the wavenumber domain quantization interval.

20. The method according to any one of claims 10-19, characterized in that, The antenna array of the network device is a one-dimensional array, and the spatial orthogonal basis is represented as follows: Where N is the number of antennas or antenna ports in the antenna array in one polarization direction. Let κ be the i-th spatial basis vector in the spatial orthogonal basis. i This represents the i-th wavenumber domain coordinate among the L wavenumber domain coordinates, where r = [r1 r2 …r n ] T r n This represents the coordinates of the nth antenna or antenna port in the antenna array, where n = 1, 2, ..., N; or, The antenna array of the network device is a two-dimensional array, and the spatial orthogonal basis is represented as follows: Wherein, N1 is the number of antennas or antenna ports in the horizontal direction of the antenna array in one polarization direction, and N2 is the number of antennas or antenna ports in the vertical direction of the antenna array in one polarization direction. Let be the i-th spatial basis vector in the spatial orthogonal basis, (κ) h,i ,κ v,i () represents the i-th wavenumber domain coordinate among the L wavenumber domain coordinates. The coordinates of the antenna or antenna port in the n2th row and n1th column of the antenna array are given, where n1 = 1, 2, ..., N1 and n2 = 1, 2, ..., N2.

21. A communication method, characterized in that, The method includes: The network device sends first information to the terminal, the first information being used to indicate L wavenumber domain coordinates, where L is a positive integer; The terminal determines a spatial orthogonal basis based on the L wavenumber domain coordinates. The spatial orthogonal basis includes L spatial basis vectors, and the L spatial basis vectors correspond one-to-one with the L wavenumber domain coordinates.

22. A communication device, characterized in that, The communication device is used to perform the communication method according to any one of claims 1-9 and 10-20.

23. A communication system, characterized in that, The device includes a terminal and a network device, wherein the terminal is configured to implement the communication method according to any one of claims 1-9, and the network device is configured to implement the communication method according to any one of claims 10-20.

24. A storage medium storing instructions, characterized in that, When the instruction is executed on the communication device, the communication device performs the communication method as described in any one of claims 1-9 and 10-20.

25. A program product comprising at least one of a program and instructions, characterized in that, When at least one of the programs or instructions is executed by the communication device, it implements the steps of the method according to any one of claims 1-9 and 10-20.

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