Communication method and apparatus

Abstract

A communication method and apparatus, relating to the technical field of communications, and capable of increasing the density of codebook sets and improving the uplink coverage performance. The method comprises: a terminal device receiving first indication information; and performing precoding on a signal on the basis of a first precoding matrix, wherein the first indication information is used for indicating the first precoding matrix; the first precoding matrix is comprised in a first precoding matrix set, each precoding matrix in the first precoding matrix set is a matrix of N rows and 1 column, and N is the number of antenna ports of the terminal device; the first precoding matrix set comprises some or all of precoding matrices in a second precoding matrix set, the second precoding matrix set comprises X precoding matrices, X is determined on the basis of N and the number of phases corresponding to a modulation mode, and X is greater than 4; elements in a first row of each precoding matrix in the second precoding matrix set are 1, and elements in a second row to an N-th row are determined on the basis of the phases corresponding to the modulation mode.

Description

Communication methods and devices

[0001] This application claims priority to Chinese Patent Application No. 202411957589.4, filed with the State Intellectual Property Office of China on December 25, 2024, entitled "Communication Method and Apparatus", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of communication technology, and in particular to communication methods and apparatus. Background Technology

[0003] In a communication system, network devices can determine the codebook set based on the number of antenna ports of the terminal devices, and determine the uplink channel based on the uplink reference signal transmitted by the terminal devices or the reciprocity of the uplink channel. Then, they can determine the precoding matrix from the codebook set based on the uplink channel. Furthermore, the network devices can send downlink control information (DCI) to the terminal devices. The DCI may include a transmitted precoding matrix indicator (TPMI), which is used to indicate the precoding matrix. Correspondingly, the terminal devices can add digital precoding to the transmitted signal based on the precoding matrix to adjust the channels at both ends of the transmission and reception, thereby improving uplink coverage performance.

[0004] Although terminal devices can determine the precoding matrix based on the above methods to achieve communication with network devices, uplink coverage performance still needs to be improved. Summary of the Invention

[0005] This application provides a communication method and apparatus that can increase the density of the codebook set and improve uplink coverage performance.

[0006] Firstly, this application provides a communication method that can be executed by a terminal device. Unless otherwise specified, "terminal device" in this application can refer to the terminal device itself, a component within the terminal device (e.g., a processor, chip, or chip system), or a logic module or software capable of implementing all or part of the terminal device's functions. The method includes: the terminal device receiving first indication information; and precoding a signal according to a first precoding matrix. The first indication information indicates the first precoding matrix; the first precoding matrix is ​​contained in a first precoding matrix set, where the precoding matrices in the first precoding matrix set are N x 1 matrices, and N is the number of antenna ports of the terminal device; the first precoding matrix set includes some or all of the precoding matrices in a second precoding matrix set, where the second precoding matrix set includes X precoding matrices, where X is determined based on N and the number of phases corresponding to the modulation scheme, and X is greater than 4; the elements in the first row of the precoding matrices in the second precoding matrix set are 1, and the elements in the second to Nth rows are determined based on the phases corresponding to the modulation scheme; N and X are both positive integers.

[0007] Based on the first aspect, the terminal device can precode the signal according to the first precoding matrix in the first precoding matrix set, which may include a second precoding matrix set. On one hand, the precoding matrices in the second precoding matrix set can be determined according to the phase corresponding to the modulation scheme, making the directions of the precoding matrices in the second precoding matrix set more dense, thus improving uplink coverage performance. On the other hand, the direction of signal transmission by the terminal device varies in different communication scenarios. Because the directions of the precoding matrices in the second precoding matrix set are more dense, the determined first precoding matrix can better meet the communication needs of the terminal device, improving communication reliability and thus enhancing communication performance.

[0008] In one possible implementation, X is the (N-1)th power of the number of phases corresponding to the modulation scheme.

[0009] In one possible implementation, the elements of the k-th row of the precoding matrix in the second precoding matrix set are determined according to one of the phases corresponding to the modulation scheme, k = 2, 3, ..., N.

[0010] Based on the two possible implementations mentioned above, the elements of the k-th row in the determined precoding matrix can traverse all phases in the phase corresponding to the modulation scheme, which can make the directions corresponding to the precoding matrices in the second precoding matrix set more dense and improve uplink coverage performance.

[0011] In one possible implementation, the precoding matrices in the second precoding matrix set include a first matrix and a second matrix. The absolute value of the difference between the phase corresponding to the element in each row of the first matrix and the phase corresponding to the element in a row of the second matrix is ​​the first phase difference. The first matrix and the second matrix are both A-row, 1-column matrices, where A is a positive integer less than or equal to N / 2.

[0012] Based on this possible implementation, the directions corresponding to the precoding matrices in the determined second precoding matrix set can be made as uniform as possible, which can improve uplink coverage performance. In addition, the second possible design results in a smaller number of precoding matrices in the determined second precoding matrix set, which can reduce the storage requirements of the second precoding matrix set.

[0013] Where the first precoding matrix set includes all the precoding matrices in the second precoding matrix set, the overhead of the first indication information can be reduced.

[0014] In one possible implementation, the first phase difference is contained in a first set; wherein the first set is determined according to the phase corresponding to the modulation scheme, or the first set is predefined.

[0015] Optionally, the terminal device may receive fourth indication information from the network device, which is used to indicate the first set.

[0016] Based on this possible implementation, if the first set is predefined, the terminal device can directly determine the first set, and then determine the precoding matrix based on the phase difference in the first set, which can reduce the workload of the terminal device and reduce transmission overhead. If the first set is determined according to the phase corresponding to the modulation scheme, the first set can be dynamically determined according to the actual communication situation, which can improve the flexibility and versatility of determining the first set.

[0017] In one possible implementation, the first set includes the absolute value of the difference between any two phases corresponding to the modulation scheme.

[0018] Based on this possible implementation, a feasible solution is provided for determining the first set. The precoding matrix is ​​determined according to the difference between any two phases in the phase corresponding to the modulation method. This can make the direction of the determined precoding matrix as uniform as possible, which can improve uplink coverage performance.

[0019] In one possible implementation, the first indication information is used to indicate the index of the first precoding matrix in the first set of precoding matrices; or, the terminal device receives second indication information, which is used to indicate a subset of precoding matrices, and the first indication information is used to indicate the index of the first precoding matrix in the subset of precoding matrices.

[0020] Based on this possible implementation, on the one hand, the terminal device can determine a subset of the precoding matrix through the second indication information and indicate the index of the first precoding matrix in the subset through the first indication information. That is, the first precoding matrix can be determined through a two-level indication method, which can reduce the number of bits occupied by the first indication information and reduce transmission overhead. At the same time, when the first indication information is located in the DCI, modifications to the first indication information can be avoided as much as possible, thereby avoiding the addition of new DCI types. On the other hand, the first indication information can directly indicate the index of the first precoding matrix in the first precoding matrix set. That is, the terminal device can determine the first precoding matrix through a single-level indication method. In the case of two-level indication, the update cycle of the second indication information is relatively long, and the first indication information can indicate a precoding matrix in a subset of the precoding matrix for a period of time, which is equivalent to the precoding matrix in the first precoding matrix set becoming sparse. However, in the case of single-level indication, the first indication information can always indicate a precoding matrix in the first precoding matrix set, which can improve transmission performance and uplink coverage performance.

[0021] In one possible implementation, the beam angles corresponding to the precoding matrices in the precoding matrix subset are located within a preset range.

[0022] Based on this possible implementation, multiple subsets of precoding matrices can be determined from the first set of precoding matrices according to the beam angle corresponding to the precoding matrix, such that the directions corresponding to precoding matrices belonging to the same set of precoding matrices are similar. This allows network devices to roughly determine the subset of precoding matrices in which the first precoding matrix is ​​located by combining the orientation of the terminal device when determining the first precoding matrix, thereby improving the accuracy of determining the first precoding matrix and thus improving the reliability of communication.

[0023] In one possible implementation, the number of precoding matrices in the precoding matrix subset is less than or equal to 2 to the power of K, where K is the number of bits occupied by the first indication information.

[0024] Based on this possible implementation, the first indication information can be used to indicate any precoding matrix in the precoding matrix subset, providing a feasible solution for determining the precoding matrix subset.

[0025] In this system, the first precoding matrix set contains a large number of precoding matrices. Using the first indication information to indicate the first precoding matrix in the first precoding matrix set would increase the number of bits occupied by the first indication information, significantly impacting the communication protocol and increasing the signaling overhead of the network device. If the first indication information is used to indicate the first precoding matrix in a subset of precoding matrices, this can be achieved by adding second indication information, keeping the number of bits occupied by the first indication information unchanged, simplifying implementation, and reducing complexity. Furthermore, the communication system contains multiple terminal devices with varying capabilities. For example, one or more terminal devices may not support precoding signals using the precoding matrices in the first precoding matrix set described in this application. Using the first indication information to indicate the first precoding matrix in a subset of precoding matrices provides better compatibility with terminal devices that do not support precoding signals using the precoding matrices in the first precoding matrix set.

[0026] In one possible implementation, the precoding matrix subset includes a third matrix and a fourth matrix. The absolute value of the difference between the phase corresponding to the element in each row of the third matrix and the phase corresponding to the element in each row of the fourth matrix is ​​the second phase difference. Both the third matrix and the fourth matrix are B-row, 1-column matrices, where B is a positive integer and B is less than or equal to N / 2.

[0027] Based on this possible implementation, the terminal device can determine the third and fourth matrices according to the second phase difference, and then determine the precoding matrix in the precoding matrix subset. This can make the corresponding directions of the precoding matrices in the precoding matrix subset as uniform as possible, thereby improving uplink coverage performance.

[0028] In one possible implementation, the second phase difference is determined based on the phase corresponding to the modulation scheme; or, the second phase difference is predefined.

[0029] Optionally, the terminal device may receive a fifth indication information from the network device, which is used to indicate the second phase difference.

[0030] Based on this possible implementation, if the second phase difference is predefined, the terminal device can directly determine the second phase difference, and then determine the precoding matrix based on the second phase difference, which can reduce the workload of the terminal device and reduce transmission overhead. If the second phase difference is determined according to the phase corresponding to the modulation method, the terminal device can dynamically determine the second phase difference according to the actual communication situation, which can improve the flexibility and versatility of determining the second phase difference.

[0031] In one possible implementation, the second phase difference is the absolute value of the difference between any two phases corresponding to the modulation scheme.

[0032] Based on this possible implementation, a feasible scheme is provided for determining the second phase difference.

[0033] In one possible implementation, the precoding matrix subset includes C precoding matrices in the second precoding matrix set, wherein the angle between each of the C precoding matrices and the fifth matrix is ​​the sum of the first angle and one of the angle intervals between the first and second precoding matrices. The fifth matrix is ​​any precoding matrix in the second precoding matrix set, and the first angle is the minimum angle between each precoding matrix in the second precoding matrix set other than the fifth matrix and the fifth matrix.

[0034] Based on this possible implementation, the terminal device can determine C precoding matrices from the second precoding matrix set as a subset of precoding matrices. Since the angle between each of the C precoding matrices and the fifth matrix is ​​the sum of the first angle and one of the angle intervals from one or more angle intervals, the directions corresponding to the C precoding matrices can be made as uniform as possible, which can improve uplink coverage performance.

[0035] In one possible implementation, the terminal device receives third indication information from the network device; wherein the third indication information is used to instruct the terminal device to precode the signal using a precoding matrix from the first set of precoding matrices.

[0036] Optionally, the third indication information is used to indicate whether the terminal device uses a precoding matrix from the first precoding matrix set to precode the signal; or, the third indication information is used to indicate whether the terminal device uses a precoding matrix from the first precoding matrix set or a subset of precoding matrices to precode the signal.

[0037] Based on this possible implementation, the terminal device can determine the set of precoding matrices specifically used for precoding, which can improve the effectiveness of information exchange between the terminal device and the network device. In addition, since the terminal device and the network device can determine the same set of precoding matrices based on the third indication information, they can determine the same first precoding matrix, which can improve the reliability of communication.

[0038] In one possible implementation, the terminal device sends its capability information to the network device; wherein the capability information is used to indicate whether the terminal device supports precoding the signal using precoding matrices in the first set of precoding matrices.

[0039] Based on this possible implementation, the terminal device can use capability information to indicate to the network device whether it supports using a precoding matrix from the first precoding matrix set to precode the signal. This can minimize the possibility of the network device instructing the terminal device to use a precoding matrix from the first precoding matrix set to precode the signal, but the terminal device is unable to determine the precoding matrix. This can reduce resource waste and improve communication reliability.

[0040] In one possible implementation, the first precoding matrix set further includes a third precoding matrix set; wherein the third precoding matrix set includes partially phase-intervention coding matrices; wherein one or more elements in the partially phase-intervention coding matrices are 0.

[0041] Based on this possible implementation, partial phase interference coding matrices can be used to reduce the requirements on the antenna capabilities of terminal devices (e.g., when the antenna capabilities of terminal devices are poor, the correlation between different antennas is high, and simultaneous transmission of signals will lead to strong interference). By sacrificing some of the spatial diversity gain brought by multiple antennas and obtaining more independent channels, the reliability of communication can be improved.

[0042] In one possible implementation, when the first precoding matrix set includes some precoding matrices from the second precoding matrix set, the partial precoding matrices are Z precoding matrices from the precoding matrices in the second precoding matrix set excluding the fourth precoding matrix set. The first value corresponding to the z-th precoding matrix among the Z precoding matrices is greater than or equal to the first value corresponding to any precoding matrix in the second precoding matrix set excluding the Z precoding matrices and the fourth precoding matrix set. The first value corresponding to the precoding matrix is ​​determined based on the precoding matrix and the fourth precoding matrix set; z = 1, 2, ..., Z, where Z is a positive integer.

[0043] The number of precoding matrices in the fourth precoding matrix set is less than the number of precoding matrices in the second precoding matrix set.

[0044] In one possible implementation, the first precoding matrix set also includes a fourth precoding matrix set.

[0045] Based on the two possible implementations mentioned above, the first precoding matrix set can include some precoding matrices (i.e., Z precoding matrices) from the second precoding matrix set, in addition to the fourth precoding matrix set. This can make the directions corresponding to the precoding matrices in the first precoding matrix set more dense, thereby improving uplink coverage performance.

[0046] In one possible implementation, the first value corresponding to the precoding matrix is ​​the sum of the cosine values ​​of the angles between the precoding matrix and the precoding matrices in the fourth set of precoding matrices; or, the first value corresponding to the precoding matrix is ​​the weighted average of the cosine values ​​of the angles between the precoding matrix and the precoding matrices in the fourth set of precoding matrices; or, the first value corresponding to the precoding matrix is ​​the maximum value among the angles between the precoding matrix and the precoding matrices in the fourth set of precoding matrices.

[0047] Based on this possible implementation, the terminal device can determine Z precoding matrices according to the cosine of the angle between the precoding matrices in the second precoding matrix set and the precoding matrices in the fourth precoding matrix set. This results in a larger angle between the direction corresponding to each of the Z determined precoding matrices and the direction corresponding to the precoding matrices in the fourth precoding matrix set, which can make the directions corresponding to the precoding matrices in the first precoding matrix set more dispersed, thereby improving uplink coverage performance.

[0048] Secondly, this application provides a communication method that can be executed by a network device. Unless otherwise specified, "network device" in this application can refer to the network device itself, a component within the network device (e.g., a processor, chip, or chip system), or a logic module or software capable of implementing all or part of the network device's functions. The method includes: the network device acquiring first indication information; wherein the first indication information is used to indicate a first precoding matrix; the first precoding matrix is ​​contained in a first precoding matrix set; and transmitting the first indication information. The precoding matrices in the first precoding matrix set are N x 1 matrices, where N is the number of antenna ports of the terminal device; the first precoding matrix set includes some or all of the precoding matrices in a second precoding matrix set, which includes X precoding matrices, where X is determined based on N and the number of phases corresponding to the modulation scheme, and X is greater than 4; the elements in the first row of the precoding matrices in the second precoding matrix set are 1, and the elements in the second to Nth rows are determined based on the phases corresponding to the modulation scheme; N and X are both positive integers.

[0049] Based on the second aspect, the network device can precode the signal according to the first precoding matrix in the first precoding matrix set, which may include the second precoding matrix set. On one hand, the precoding matrices in the second precoding matrix set can be determined according to the phase corresponding to the modulation scheme, making the directions of the precoding matrices in the second precoding matrix set more dense, thus improving uplink coverage performance. On the other hand, the direction of signal transmission by the terminal device varies in different communication scenarios. Because the directions of the precoding matrices in the second precoding matrix set are more dense, the determined first precoding matrix can better meet the communication needs of the terminal device, improving communication reliability and thus enhancing communication performance.

[0050] In one possible implementation, X is the (N-1)th power of the number of phases corresponding to the modulation scheme.

[0051] In one possible implementation, the elements of the k-th row of the precoding matrix in the second precoding matrix set are determined according to one of the phases corresponding to the modulation scheme, k = 2, 3, ..., N.

[0052] Based on the two possible implementations mentioned above, the elements of the k-th row in the determined precoding matrix can traverse all phases in the phase corresponding to the modulation scheme, which can make the directions corresponding to the precoding matrices in the second precoding matrix set more dense and improve uplink coverage performance.

[0053] In one possible implementation, the precoding matrices in the second precoding matrix set include a first matrix and a second matrix. The absolute value of the difference between the phase corresponding to the element in each row of the first matrix and the phase corresponding to the element in a row of the second matrix is ​​the first phase difference. The first matrix and the second matrix are both A-row, 1-column matrices, where A is a positive integer less than or equal to N / 2.

[0054] Based on this possible implementation, the directions corresponding to the precoding matrices in the determined second precoding matrix set can be made as uniform as possible, which can improve uplink coverage performance. Furthermore, since the number of terminal devices in the second precoding matrix set determined by the above method is relatively small, the storage requirements for the second precoding matrix set can be reduced.

[0055] Where the first precoding matrix set includes all the precoding matrices in the second precoding matrix set, the overhead of the first indication information can be reduced.

[0056] In one possible implementation, the first phase difference is contained in a first set; wherein the first set is determined according to the phase corresponding to the modulation scheme, or the first set is predefined.

[0057] Optionally, the network device may send a fourth indication message to the terminal device, the fourth indication message being used to indicate the first set.

[0058] Based on this possible implementation, if the first set is predefined, the network device can directly determine the first set, and then determine the precoding matrix based on the phase difference in the first set, which can reduce the workload of the network device and reduce transmission overhead. If the first set is determined according to the phase corresponding to the modulation scheme, the first set can be dynamically determined according to the actual communication situation, which can improve the flexibility and versatility of determining the first set.

[0059] In one possible implementation, the first set includes the absolute value of the difference between any two phases corresponding to the modulation scheme.

[0060] Based on this possible implementation, a feasible solution is provided for determining the first set. The precoding matrix is ​​determined according to the difference between any two phases in the phase corresponding to the modulation method. This can make the direction of the determined precoding matrix as uniform as possible, which can improve uplink coverage performance.

[0061] In one possible implementation, the first indication information is used to indicate the index of the first precoding matrix in the first set of precoding matrices; or, the network device sends a second indication information, which is used to indicate a subset of precoding matrices, and the first indication information is used to indicate the index of the first precoding matrix in the subset of precoding matrices.

[0062] Based on this possible implementation, on the one hand, the terminal device can determine a subset of the precoding matrix through the second indication information and indicate the index of the first precoding matrix in the subset through the first indication information. That is, the first precoding matrix can be determined through a two-level indication method, which can reduce the number of bits occupied by the first indication information and reduce transmission overhead. At the same time, when the first indication information is located in the DCI, modifications to the first indication information can be avoided as much as possible, thereby avoiding the addition of new DCI types. On the other hand, the first indication information can directly indicate the index of the first precoding matrix in the first precoding matrix set. That is, the terminal device can determine the first precoding matrix through a single-level indication method. In the case of two-level indication, the update cycle of the second indication information is relatively long, and the first indication information can indicate a precoding matrix in a subset of the precoding matrix for a period of time, which is equivalent to the precoding matrix in the first precoding matrix set becoming sparse. However, in the case of single-level indication, the first indication information can always indicate a precoding matrix in the first precoding matrix set, which can improve transmission performance and uplink coverage performance.

[0063] In one possible implementation, the beam angles corresponding to the precoding matrices in the precoding matrix subset are located within a preset range.

[0064] Based on this possible implementation, multiple subsets of precoding matrices can be determined from the first set of precoding matrices according to the beam angle corresponding to the precoding matrix, so that the directions corresponding to the precoding matrices belonging to the same set of precoding matrices are similar. When determining the first precoding matrix, the network device can roughly determine the subset of precoding matrices in which the first precoding matrix is ​​located by combining the orientation of the terminal device, which can improve the accuracy of determining the first precoding matrix and thus improve the reliability of communication.

[0065] In one possible implementation, the number of precoding matrices in the precoding matrix subset is less than or equal to 2 to the power of K, where K is the number of bits occupied by the first indication information.

[0066] Based on this possible implementation, the first indication information can be used to indicate any precoding matrix in the precoding matrix subset, providing a feasible solution for determining the precoding matrix subset.

[0067] In this system, the first precoding matrix set contains a large number of precoding matrices. Using the first indication information to indicate the first precoding matrix in the first precoding matrix set would increase the number of bits occupied by the first indication information, significantly impacting the communication protocol and increasing the signaling overhead of the network device. If the first indication information is used to indicate the first precoding matrix in a subset of precoding matrices, this can be achieved by adding second indication information, keeping the number of bits occupied by the first indication information unchanged, simplifying implementation, and reducing complexity. Furthermore, the communication system contains multiple terminal devices with varying capabilities. For example, one or more terminal devices may not support precoding signals using the precoding matrices in the first precoding matrix set described in this application. Using the first indication information to indicate the first precoding matrix in a subset of precoding matrices provides better compatibility with terminal devices that do not support precoding signals using the precoding matrices in the first precoding matrix set.

[0068] In one possible implementation, the precoding matrix subset includes a third matrix and a fourth matrix. The absolute value of the difference between the phase corresponding to the element in each row of the third matrix and the phase corresponding to the element in each row of the fourth matrix is ​​the second phase difference. Both the third matrix and the fourth matrix are B-row, 1-column matrices, where B is a positive integer and B is less than or equal to N / 2.

[0069] Based on this possible implementation, network devices can determine the third and fourth matrices according to the second phase difference, and then determine the precoding matrices in the precoding matrix subset. This can make the corresponding directions of the precoding matrices in the precoding matrix subset as uniform as possible, thereby improving uplink coverage performance.

[0070] In one possible implementation, the second phase difference is determined based on the phase corresponding to the modulation scheme; or, the second phase difference is predefined.

[0071] Optionally, the network device may send a fifth indication message to the terminal device, which is used to indicate the second phase difference.

[0072] Based on this possible implementation, if the second phase difference is predefined, the network device can directly determine the second phase difference, and then determine the precoding matrix based on the second phase difference, which can reduce the workload of the network device and reduce transmission overhead. If the second phase difference is determined according to the phase corresponding to the modulation scheme, the network device can dynamically determine the second phase difference according to the actual communication situation, which can improve the flexibility and versatility of determining the second phase difference.

[0073] In one possible implementation, the second phase difference is the absolute value of the difference between any two phases corresponding to the modulation scheme.

[0074] Based on this possible implementation, a feasible scheme is provided for determining the second phase difference.

[0075] In one possible implementation, the precoding matrix subset includes C precoding matrices in the second precoding matrix set, wherein the angle between each of the C precoding matrices and the fifth matrix is ​​the sum of the first angle and one of the angle intervals from one or more angle intervals, the fifth matrix is ​​any precoding matrix in the second precoding matrix set, and the first angle is the minimum value of the angle between each precoding matrix other than the fifth matrix in the second precoding matrix set and the fifth matrix.

[0076] Based on this possible implementation, the terminal device can determine C precoding matrices from the second precoding matrix set as a subset of precoding matrices. Since the angle between each of the C precoding matrices and the fifth matrix is ​​the sum of the first angle and one of the angle intervals from one or more angle intervals, the directions corresponding to the C precoding matrices can be made as uniform as possible, which can improve uplink coverage performance.

[0077] In one possible implementation, the network device sends a third instruction message; wherein the third instruction message instructs the terminal device to precode the signal using a precoding matrix from the first set of precoding matrices.

[0078] Optionally, the third indication information is used to indicate whether the terminal device uses a precoding matrix from the first precoding matrix set to precode the signal; or, the third indication information is used to indicate whether the terminal device uses a precoding matrix from the first precoding matrix set or a subset of precoding matrices to precode the signal.

[0079] Based on this possible implementation, network devices can indicate to terminal devices the set of precoding matrices containing the precoding matrices used for precoding, which can improve the effectiveness of information exchange between terminal devices and network devices. In addition, since terminal devices and network devices can determine the same set of precoding matrices based on the third indication information, they can determine the same first precoding matrix, which can improve the reliability of communication.

[0080] In one possible implementation, the network device receives capability information from the terminal device; wherein the capability information is used to indicate whether the terminal device supports precoding the signal using precoding matrices in a first set of precoding matrices.

[0081] Based on this possible implementation, network devices can determine whether terminal devices support using precoding matrices from the first precoding matrix set to precode signals through capability information. This can minimize situations where the network device instructs the terminal device to use a precoding matrix from the first precoding matrix set to precode signals, but the terminal device is unable to determine the precoding matrix. This can reduce resource waste and improve communication reliability.

[0082] In one possible implementation, the first precoding matrix set further includes a third precoding matrix set; wherein the third precoding matrix set includes partially phase-intervention coding matrices; wherein one or more elements in the partially phase-intervention coding matrices are 0.

[0083] Based on this possible implementation, partial phase interference coding matrices can be used to reduce the requirements on the antenna capabilities of terminal devices (e.g., when the antenna capabilities of terminal devices are poor, the correlation between different antennas is high, and simultaneous transmission of signals will lead to strong interference). By sacrificing some of the spatial diversity gain brought by multiple antennas and obtaining more independent channels, the reliability of communication can be improved.

[0084] In one possible implementation, when the first precoding matrix set includes some precoding matrices from the second precoding matrix set, the partial precoding matrices are Z precoding matrices from the precoding matrices in the second precoding matrix set excluding the fourth precoding matrix set. The first value corresponding to the z-th precoding matrix among the Z precoding matrices is greater than or equal to the first value corresponding to any precoding matrix in the second precoding matrix set excluding the Z precoding matrices and the fourth precoding matrix set. The first value corresponding to the precoding matrix is ​​determined based on the precoding matrix and the fourth precoding matrix set; z = 1, 2, ..., Z, where Z is a positive integer.

[0085] The number of precoding matrices in the fourth precoding matrix set is less than the number of precoding matrices in the second precoding matrix set.

[0086] In one possible implementation, the first precoding matrix set also includes a fourth precoding matrix set.

[0087] Based on the two possible implementations mentioned above, the first precoding matrix set can include some precoding matrices (i.e., Z precoding matrices) from the second precoding matrix set, in addition to the fourth precoding matrix set. This can make the directions corresponding to the precoding matrices in the first precoding matrix set more dense, thereby improving uplink coverage performance.

[0088] In one possible implementation, the first value corresponding to the precoding matrix is ​​the sum of the cosine values ​​of the angles between the precoding matrix and the precoding matrices in the fourth set of precoding matrices; or, the first value corresponding to the precoding matrix is ​​the weighted average of the cosine values ​​of the angles between the precoding matrix and the precoding matrices in the fourth set of precoding matrices; or, the first value corresponding to the precoding matrix is ​​the maximum value among the angles between the precoding matrix and the precoding matrices in the fourth set of precoding matrices.

[0089] Based on this possible implementation, the terminal device can determine Z precoding matrices according to the cosine of the angle between the precoding matrices in the second precoding matrix set and the precoding matrices in the fourth precoding matrix set. This results in a larger angle between the direction corresponding to each of the Z determined precoding matrices and the direction corresponding to the precoding matrices in the fourth precoding matrix set, which can make the directions corresponding to the precoding matrices in the first precoding matrix set more dispersed, thereby improving uplink coverage performance.

[0090] Thirdly, embodiments of this application provide a communication device that can be applied to the terminal device described in the first aspect to realize the functions performed by the terminal device. The communication device can be the terminal device itself, or it can be a chip, chip system, or system-on-a-chip (SoC) of the terminal device. The communication device can execute the functions performed by the terminal device through hardware or through corresponding software. The hardware or software includes one or more modules corresponding to the functions described above. For example, a transceiver module and a processing module. The transceiver module can independently complete the following transceiver operations or cooperate with the processing module to complete the following transceiver operations; correspondingly, the processing module can independently complete the following processing operations or cooperate with the transceiver module to complete the following processing operations, without limitation.

[0091] For example, a transceiver module is used to receive first indication information; wherein the first indication information is used to indicate a first precoding matrix; the first precoding matrix is ​​contained in a first precoding matrix set, and the precoding matrices in the first precoding matrix set are N-row, 1-column matrices, where N is the number of antenna ports of the terminal device; the first precoding matrix set includes some or all of the precoding matrices in a second precoding matrix set, the second precoding matrix set includes X precoding matrices, where X is determined according to N and the number of phases corresponding to the modulation method, and X is greater than 4; the elements in the first row of the precoding matrices in the second precoding matrix set are 1, and the elements in the second to Nth rows are determined according to the phases corresponding to the modulation method; N and X are both positive integers. A processing module is used to precode the signal according to the first precoding matrix.

[0092] Optionally, the transceiver module and processing module of the communication device in the third aspect may also perform the corresponding functions in the first aspect or any possible design of the first aspect, as detailed in the method examples, and the beneficial effects that can be achieved can also be found in the foregoing related content.

[0093] Fourthly, embodiments of this application provide a communication device that can be applied to the network device described in the second aspect to realize the functions performed by the network device. The communication device can be a network device, or a chip, chip system, or system-on-a-chip (SoC) of the network device. The communication device can execute the functions performed by the network device through hardware or through corresponding software. The hardware or software includes one or more modules corresponding to the functions described above. For example, a transceiver module and a processing module. The transceiver module can independently complete the following transceiver operations or cooperate with the processing module to complete the following transceiver operations; correspondingly, the processing module can independently complete the following processing operations or cooperate with the transceiver module to complete the following processing operations, without limitation.

[0094] For example, a processing module is used to acquire first indication information; wherein, the first indication information is used to indicate a first precoding matrix; the first precoding matrix is ​​contained in a first precoding matrix set, the precoding matrix in the first precoding matrix set is an N-row, 1-column matrix, where N is the number of antenna ports of the terminal device; the first precoding matrix set includes some or all of the precoding matrices in a second precoding matrix set, the second precoding matrix set includes X precoding matrices, where X is determined according to N and the number of phases corresponding to the modulation method, and X is greater than 4; the elements of the first row of the precoding matrix in the second precoding matrix set are 1, and the elements of the second to Nth rows are determined according to the phases corresponding to the modulation method; N and X are both positive integers; and a transceiver module is used to transmit the first indication information.

[0095] Optionally, the transceiver module and processing module of the communication device in the fourth aspect may also perform the corresponding functions in the second aspect or any possible design of the second aspect, as detailed in the method examples, and the beneficial effects that can be achieved can also be found in the foregoing related content.

[0096] Fifthly, embodiments of this application provide a communication device, which includes one or more processors; the one or more processors are configured to run computer programs or instructions, such that when the one or more processors execute the computer instructions or instructions, the communication method described in any one of the first to second aspects is performed.

[0097] In one possible design, the communication device further includes one or more memories coupled to one or more processors, the memories used to store the aforementioned computer programs or instructions. In one possible implementation, the memories are located outside the communication device. In another possible implementation, the memories are located inside the communication device. In embodiments of this application, the processor and memory may also be integrated into a single device, i.e., the processor and memory may be integrated together. In one possible implementation, the communication device further includes a transceiver for receiving and / or transmitting information.

[0098] In one possible design, the communication device further includes one or more communication interfaces coupled to one or more processors, and the communication interfaces are used to communicate with other modules outside the communication device.

[0099] In a sixth aspect, embodiments of this application provide a communication device, which includes an interface circuit and a logic circuit; the interface circuit is used to input and / or output information; the logic circuit is used to execute the communication method as described in any one of the first to second aspects, and to process and / or generate information based on the information.

[0100] In a seventh aspect, embodiments of this application provide a computer-readable storage medium storing computer instructions or programs that, when executed on a computer, cause the communication method described in any one of the first to second aspects to be performed.

[0101] Eighthly, embodiments of this application provide a computer program product containing computer instructions that, when run on a computer, causes the communication method described in any one of the first to second aspects to be executed.

[0102] Ninthly, embodiments of this application provide a computer program that, when run on a computer, causes the communication method described in any one of the first to second aspects to be executed.

[0103] In a tenth aspect, embodiments of this application provide a chip, including: a processor coupled to a memory, the memory being used to store programs or instructions, wherein when the program or instructions are executed by the processor, the communication method as described in the first to second aspects is executed.

[0104] The technical effects of any of the design methods in aspects three through ten are similar to those in aspects one through two, and will not be elaborated upon further.

[0105] Eleventhly, embodiments of this application provide a communication system that may include communication means for performing the communication as described in the first aspect or any possible design of the first aspect, and communication means for performing the communication as described in the second aspect or any possible design of the second aspect. Attached Figure Description

[0106] Figure 1 is a schematic diagram of a signal precoding process provided in an embodiment of this application;

[0107] Figure 2 is a schematic diagram of a communication system provided in an embodiment of this application;

[0108] Figure 3 is a schematic diagram of signaling interaction between a terminal device and a network device according to an embodiment of this application;

[0109] Figure 4 is a schematic diagram of the structure of a communication device provided in an embodiment of this application;

[0110] Figure 5 is a flowchart illustrating a communication method provided in an embodiment of this application;

[0111] Figure 6 is a flowchart illustrating another communication method provided in an embodiment of this application;

[0112] Figure 7 is a structural schematic diagram of a terminal device provided in an embodiment of this application;

[0113] Figure 8 is a schematic diagram of the structure of a network device provided in an embodiment of this application;

[0114] Figure 9 is a schematic diagram of another communication device provided in an embodiment of this application. Detailed Implementation

[0115] Before describing the embodiments of this application, the technical terms involved in the embodiments of this application will be described.

[0116] Multiple-input multiple-output (MIMO): Massive MIMO is a technology proposed by the New Radio (NR) standard to improve spatial resolution, increase spatial multiplexing dimensions, and obtain array gain. In 3GPP Release 18, the 6425MHz–7125MHz frequency band was defined as the U6G licensed band. Compared to carrier frequencies such as 2.6GHz and 3.5GHz, the U6G band has a higher carrier frequency and a larger available bandwidth. Since the path loss of signal propagation is proportional to the square of the carrier frequency, the higher the carrier frequency, the greater the path loss, resulting in poorer signal coverage.

[0117] Terminal devices can enhance uplink coverage by precoding the signal.

[0118] Precoding: In NR MIMO systems, terminal devices can adjust the channel between the transmitter and receiver by adding digital precoding to the transmitted signal. This reduces interference between parallel data streams during demodulation by the network device, thereby improving demodulation performance. The process of adding digital precoding to the transmitted signal is called precoding.

[0119] Optionally, the specific steps for the terminal device to precode the transmitted signal can be shown in Figure 1:

[0120] Step 101: The network device sends a radio resource control (RRC) signaling message to the terminal device; correspondingly, the terminal device receives the RRC signaling message from the network device.

[0121] The RRC signaling may include physical uplink shared channel (PUSCH) configuration information.

[0122] Optionally, the PUSCH configuration information may include a `transformPrecoder` field. This field instructs the terminal device to use orthogonal frequency division multiplexing (OFDM) with discrete Fourier transform (DFT) spread spectrum (DFT-S-OFDM) for signal transmission. In other words, the terminal device can map the transmitted signal onto a DFT-S-OFDM waveform for signal transmission.

[0123] Understandably, the NR standard requires terminal devices to support both cyclically prefixed (CP)-OFDM and DFT-S-OFDM waveforms simultaneously. DFT-S-OFDM is designed for coverage-constrained scenarios and is only suitable for single-stream transmission. However, DFT-S-OFDM has a lower peak-to-average power ratio (PAPR), meaning that at the same average transmit power, DFT-S-OFDM has a lower PAPR than CP-OFDM. This makes the power amplifier corresponding to DFT-S-OFDM less likely to enter the nonlinear region, thus reducing the likelihood of nonlinear signal distortion. Since nonlinear distortion incurs additional losses, a lower PAPR and less nonlinear distortion mean less loss for the same transmit power, improving coverage performance. Therefore, network devices can instruct terminal devices to use DFT-S-OFDM waveforms to transmit signals, thereby enhancing coverage performance.

[0124] Step 102: The terminal device sends an uplink reference signal to the network device; correspondingly, the network device receives the uplink reference signal from the terminal device.

[0125] The terminal device can determine the transmission resources based on the PUSCH configuration information and send uplink reference signals on those transmission resources.

[0126] For example, the uplink reference signal can be a sounding reference signal (SRS).

[0127] Among them, the terminal device can send uplink reference signals to the network device based on the DFT-S-OFDM waveform.

[0128] Step 103: The network device determines the status information of the uplink channel based on the uplink reference signal.

[0129] Among them, network devices can measure uplink reference signals, obtain measurement results, and determine uplink channel status information based on the measurement results.

[0130] Understandably, network devices can also send downlink reference signals to terminal devices. Correspondingly, the terminal devices measure the downlink reference signals, obtain measurement results, and report these results to the network devices. Furthermore, the network devices can determine the downlink channel state information based on the measurement results, and determine the uplink channel state information based on the reciprocity of the uplink and downlink channels.

[0131] Step 104: The network device sends a DCI to the terminal device; correspondingly, the terminal device receives the DCI from the network device.

[0132] The network device can select a precoding matrix from the predefined set of uplink codebooks for DFT-S-OFDM waveforms based on the uplink channel status information, and indicate the precoding matrix via TPMI.

[0133] In this application, the codebook set can also be understood as a precoding matrix set.

[0134] DCI may include a TPMI index, which indicates the precoding matrix selected by the network device.

[0135] Step 105: The terminal device determines the precoding matrix based on TPMI.

[0136] The terminal device can precode the transmitted signal according to the precoding matrix and then transmit the precoded transmitted signal.

[0137] Based on the content shown in Figure 1, the network device can determine the precoding matrix from the uplink codebook set corresponding to the DFT-S-OFDM waveform according to the uplink channel state information. The precoding matrix in the uplink codebook set corresponding to the DFT-S-OFDM waveform is an N-row, 1-column matrix, where N is the number of antenna ports of the terminal device. The uplink codebook set corresponding to the DFT-S-OFDM waveform can include the following cases:

[0138] In the first case, as shown in Table 1, N can be 2 (abbreviated as 2T), and TPMI can occupy three bits. That is, the network device can use TPMI to indicate the index of any precoding matrix in Table 1 (there are 2 empty indices). Among them, the first two precoding matrices are partially coherent codebooks (also called antenna selection codebooks or partial phase interferometry coding matrices), and the last four precoding matrices are fully coherent codebooks (also called fully phase interferometry coding matrices). The fully phase interferometry coding matrix is ​​based on the first antenna port, and each other antenna port is determined according to the values ​​of the four constellation points (i.e., the values ​​of the constellation points corresponding to the quadrature phase shift keying (QPSK) modulation mode: [1, -1, j, -j]).

[0139] Table 1. Dual-antenna port single-layer transmission precoding matrix

[0140] In the second case, as shown in Table 2, N can be 4 (abbreviated as 4T), and TPMI can occupy five bits. That is, the network device can use TPMI to indicate the index of any precoding matrix in Table 2 (there are 4 empty indices). Among them, the first 12 precoding matrices are partial phase interferometry (PPI) coding matrices, and the last 16 precoding matrices are full phase interferometry (MPI) coding matrices. The MPI coding matrix is ​​based on the first antenna port, and each other antenna port is determined according to the values ​​of four constellation points (i.e., the values ​​of the constellation points corresponding to the QPSK modulation method: [1, -1, j, -j]).

[0141] Table 2. Single-layer transmission precoding matrix for 4 antenna ports

[0142] In the third case, as shown in Table 3, N can be 8 (abbreviated as 8T), and TPMI can occupy four bits. That is, the network device can use TPMI to indicate the index of any precoding matrix in Table 3. The precoding matrices in Table 3 are all total phase interferometry (TPI) coding matrices. The TPI coding matrix is ​​based on the first antenna port, and each other antenna port is determined according to the values ​​of four constellation points (i.e., the values ​​of the constellation points corresponding to the QPSK modulation scheme: [1, -1, j, -j]).

[0143] Table 3. Single-layer transmission precoding matrix for 8 antenna ports

[0144] Among them, the codebook set corresponding to the DFT-S-OFDM waveform supports a maximum of 4 uplink transmit antennas. Table 3 shows the codebook set corresponding to the cyclic prefixed (CP)-OFDM waveform when the number of uplink transmit antennas is 8.

[0145] In summary, although terminal devices can determine the precoding matrix based on the above methods to achieve communication with network devices, the density (or precision) of the above codebook sets is insufficient, and the uplink coverage performance still needs to be improved.

[0146] Therefore, this application provides a communication method, which includes: a terminal device receiving first indication information; and precoding a signal according to a first precoding matrix. The first indication information indicates the first precoding matrix; the first precoding matrix is ​​contained in a first precoding matrix set, wherein the precoding matrices in the first precoding matrix set are N x 1 matrices, where N is the number of antenna ports of the terminal device; the first precoding matrix set includes some or all of the precoding matrices in a second precoding matrix set, wherein the second precoding matrix set includes X precoding matrices, where X is determined based on N and the number of phases corresponding to the modulation scheme, and X is greater than 4; the elements in the first row of the precoding matrices in the second precoding matrix set are 1, and the elements in the second to Nth rows are determined based on the phases corresponding to the modulation scheme; N and X are both positive integers.

[0147] In this embodiment, the terminal device can precode a signal according to a first precoding matrix in a first precoding matrix set, which may include a second precoding matrix set. On one hand, the precoding matrices in the second precoding matrix set can be determined based on the phase corresponding to the modulation scheme, making the directions of the precoding matrices in the second precoding matrix set more dense and improving uplink coverage performance. On the other hand, the direction of signal transmission by the terminal device varies in different communication scenarios. Because the directions of the precoding matrices in the second precoding matrix set are more dense, the determined first precoding matrix can better meet the communication needs of the terminal device, improving communication reliability and thus enhancing communication performance.

[0148] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0149] The communication method provided in this application embodiment can be used in any communication system, such as a 3GPP communication system, for example, a long term evolution (LTE) system, a fifth generation (5G) mobile communication system, a hybrid LTE and 5G network system, an NR system, an NR vehicle-to-everything (V2X) system, a device-to-device (D2D) communication system, a machine-to-machine (M2M) communication system, an Internet of Things (IoT) system, a narrow band Internet of Things (NB-IoT) system, a global system for mobile communications (GSM), an enhanced data rate for GSM evolution (EDGE) system, a wideband code division multiple access (WCDMA) system, a code division multiple access (CDMA2000) system, and a time division-synchronization code division multiple access (TDMA) system. Access, TD-SCDMA, enhanced mobile broadband (eMBB), ultra-reliable and low-latency communication (URLLC), enhanced machine-type communication (eMTC), and various types of future communication systems are not restricted. Non-terrestrial network (NTN) systems (such as satellite communication systems) and non-3GPP communication systems are also included.

[0150] The communication method provided in this application can be applied to various communication scenarios. For example, it can be applied to one or more of the following communication scenarios: coding of control channels, coding of data channels, etc., without limitation.

[0151] The communication system provided in the embodiments of this application will be described below using Figure 2 as an example.

[0152] Figure 2 is a schematic diagram of a communication system provided in an embodiment of this application. As shown in Figure 2, the communication system may include at least one terminal device and at least one network device.

[0153] In Figure 2, the terminal device can be located within the beam / cell coverage area of ​​the network device, and the network device can provide communication services to the terminal device. For example, the network device can use channel coding to encode downlink data and then transmit it to the terminal device via air interface after constellation modulation (i.e., the network device is the terminal device, and the terminal device is the network device); the terminal device can also use channel coding to encode uplink data and then transmit it to the network device via air interface after constellation modulation (i.e., the terminal device is the terminal device, and the network device is the network device). It is understood that when network devices communicate with each other, or when terminal devices communicate with each other, communication can also be based on channel coding; that is, both the terminal device and the network device can be network devices or both can be terminal devices, without restriction.

[0154] The terminal device in Figure 2 can be a device with wireless transceiver capabilities or a chip or chip system that can be configured on the device. It allows users to access the network and is used to provide voice and / or data connectivity to users. The terminal device can also be called user equipment (UE), subscriber unit, terminal, mobile station (MS), or mobile terminal (MT), etc.

[0155] For example, the terminal device can be a mobile phone, a tablet computer, or a computer with wireless transceiver capabilities. Terminal equipment can also be user stations, mobile stations, remote stations, remote terminal equipment, mobile terminal equipment, user terminal equipment, wireless communication equipment, user agents, user devices, cellular phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), handheld devices with wireless communication capabilities, computing devices, processing devices connected to wireless modems, in-vehicle equipment, wearable devices, terminal equipment in the Internet of Things (IoT), home appliances, virtual reality (VR) terminals, augmented reality (AR) terminals, wireless terminals in industrial control, wireless terminals in autonomous driving, wireless terminals in telemedicine, wireless terminals in smart grids, wireless terminals in smart cities, wireless terminals in smart homes, vehicles with vehicle-to-vehicle (V2V) communication capabilities, intelligent connected vehicles, and UAV-to-UAV communication. Unmanned aerial vehicles (UAVs) with U2U communication capabilities, terminal devices in future networks, or terminal devices in future evolved public land mobile networks (PLMNs) are not subject to restrictions.

[0156] In Figure 2, the network device can be any device deployed in the access network capable of wireless communication with terminal devices. It can also be a chip or chip system that can be configured within the aforementioned device, a logical node or logical module, or a function implemented in software. Its main responsibilities include air interface-side wireless physical control, resource scheduling, wireless resource management, quality of service management, data compression and encryption, wireless access control, and mobility management. Specifically, the network device can be either a wired access device or a wireless access device.

[0157] For example, a network device can consist of one or more access network (AN) / radio access network (RAN) nodes. AN / RAN nodes can be various types of base stations, such as: satellite base stations, evolved Node Bs (gNBs), transmission reception points (TRPs), evolved Node Bs (eNBs), radio network controllers (RNCs), Node Bs (NBs), base station controllers (BSCs), base transceiver stations (BTSs), home base stations (e.g., home evolved Node Bs, or home Node Bs (HNBs), macro base stations, micro base stations, pico base stations, small cells, relay stations, balloon stations, drone stations, wireless backhaul nodes, base band units (BBUs), or wireless fidelity (Wi-Fi) access points (APs), etc. It is understood that network devices can be terrestrial devices or non-terrestrial devices (such as satellites, drones, high-altitude communication equipment, etc.). Furthermore, in communication systems employing different wireless access technologies, the names of network devices with base station functions may differ, and this application does not impose any restrictions on this.

[0158] In another example, the network equipment may include a BBU and a remote radio unit (RRU). The BBU and RRU can be located in different places; for example, the RRU can be moved remotely to a high-traffic area, while the BBU is located in the central equipment room. The BBU and RRU can also be located in the same equipment room. The BBU and RRU can also be different components under the same rack.

[0159] In another example, the network device can be a device that includes centralized unit (CU) nodes, distributed unit (DU) nodes, or both CU and DU nodes. For instance, the network device can be logically divided into CUs and DUs, with some protocol layer functions centrally controlled by the CU, and the remaining partial or complete protocol layer functions distributed in the DU, which is centrally controlled by the CU. The CU and DU can be separate entities or included in the same network element, such as a BBU. Furthermore, the centralized unit (CU) can be further divided into a control plane (CU-CP) and a user plane (CU-UP).

[0160] In another example, the network device may also be a device that includes a radio unit (RU), or a device that includes a CU, a DU, and a RU. The RU may be included in a radio frequency device or radio frequency unit, such as an RRU, an active antenna unit (AAU), or a remote radio head (RRH).

[0161] It is understood that CU (or CU-CP and CU-UP), DU, or RU may have different names in different systems, but those skilled in the art will understand their meaning. For example, in an open radio access network (O-RAN) system, CU can also be called O-CU (open CU), DU can also be called O-DU, CU-CP can also be called O-CU-CP, CU-UP can also be called O-CU-UP, and RU can also be called O-RU. For ease of description, this application uses CU, CU-CP, CU-UP, DU, and RU as examples. Any of the units among CU (or CU-CP, CU-UP), DU, and RU in this application can be implemented through software modules, hardware modules, or a combination of software modules and hardware modules.

[0162] Based on the above description of the terminal device and network device, optionally, the communication method provided in the embodiments of this application can be implemented by the aforementioned terminal device or network device, or by components of the terminal device or network device, such as by application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or software (such as program code in memory) deployed in the terminal device or network device, without limitation.

[0163] Optionally, in this embodiment, the network device and the terminal device can interact with each other through the protocol layer. For example, as shown in Figure 3, the network device can interact with the terminal device via RRC signaling through the RRC layer. Alternatively, the network device and the terminal device can implement physical channel transmission through the physical (PHY) layer. For instance, the network device can send one or more of the following to the terminal device through the PHY layer: a physical downlink control channel (PDCCH) or a physical downlink shared channel (PDSCH); or the terminal device can send one or more of the following to the network device through the PHY layer: a physical uplink control channel (PUCCH) or a PUSCH.

[0164] In specific implementation, as shown in Figure 2, each terminal device and network device can adopt the composition structure shown in Figure 4, or include the components shown in Figure 4. Figure 4 is a schematic diagram of the structure of a communication device 400 provided in an embodiment of this application. The communication device 400 can be a terminal device or a chip or system-on-a-chip in a terminal device; it can also be a network device or a chip or system-on-a-chip in a network device. As shown in Figure 4, the communication device 400 includes a processor 401, a transceiver 402, and a communication line 403.

[0165] Furthermore, the communication device 400 may also include a memory 404. The processor 401, memory 404, and transceiver 402 can be connected via a communication line 403.

[0166] The processor 401 can be a central processing unit (CPU), a general-purpose processor, a network processor (NP), a digital signal processor (DSP), a microprocessor, a microcontroller, a programmable logic device (PLD), or any combination thereof. The processor 401 can also be other devices with processing capabilities, such as circuits, devices, or software modules, without limitation.

[0167] Transceiver 402 is used to communicate with other devices or other communication networks. These other communication networks can be Ethernet, radio access network (RAN), wireless local area network (WLAN), etc. Transceiver 402 can be a module, circuit, transceiver, or any device capable of enabling communication.

[0168] Communication line 403 is used to transmit information between the components included in communication device 400.

[0169] Memory 404 is used to store instructions. These instructions can be computer programs.

[0170] The memory 404 can be a read-only memory (ROM) or other type of static storage device that can store static information and / or instructions; it can also be a random access memory (RAM) or other type of dynamic storage device that can store information and / or instructions; it can also be an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical discs, laser discs, optical discs, digital universal optical discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, etc., without limitation.

[0171] The memory 404 may exist independently of the processor 401 or may be integrated with the processor 401. The memory 404 may be used to store instructions, program code, or some data. The memory 404 may be located within or outside the communication device 400, without limitation. The processor 401 is used to execute the instructions stored in the memory 404 to implement the communication method provided in the following embodiments of this application.

[0172] In one example, processor 401 may include one or more CPUs, such as CPU0 and CPU1 in Figure 4.

[0173] As an optional implementation, the communication device 400 may include multiple processors, for example, in addition to the processor 401 in FIG4, it may also include a processor 407.

[0174] As an optional implementation, the communication device 400 also includes an output device 405 and an input device 406. For example, the input device 406 is a device such as a keyboard, mouse, microphone, or joystick, and the output device 405 is a device such as a display screen or speaker.

[0175] The communication device 400 may be a desktop computer, a laptop computer, a web server, a mobile phone, a tablet computer, a wireless terminal, an embedded device, a chip system, or a device with a similar structure to that shown in Figure 4. Furthermore, the composition shown in Figure 4 does not constitute a limitation on the communication device. In addition to the components shown in Figure 4, the communication device may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0176] In this embodiment of the application, the chip system may be composed of chips or may include chips and other discrete devices.

[0177] Furthermore, the actions, terms, etc., involved in the various embodiments of this application can be referenced interchangeably without limitation. The message names or parameter names in the messages exchanged between the various devices in the embodiments of this application are merely examples, and other names may be used in specific implementations without limitation.

[0178] The communication method provided in the embodiments of this application will be described below with reference to the communication system shown in Figure 2 and Figure 5. The terminal device can be any terminal device or network device in the communication system shown in Figure 2, and the network device can also be any terminal device or network device in the communication system shown in Figure 2. The terminal device or network device described in the following embodiments may include the components shown in Figure 4.

[0179] Figure 5 is a flowchart of a communication method provided in an embodiment of this application. As shown in Figure 5, the method may include:

[0180] Step 501: The network device obtains the first instruction information.

[0181] The first indication information is used to indicate the first precoding matrix. For example, the first indication information can be TPMI.

[0182] Optionally, the first indication information may be located in the DCI, or the first indication information may be located in the RRC message, or the first indication information may be located in the system message, without restriction.

[0183] The first precoding matrix is ​​contained in the first precoding matrix set, that is, the first precoding matrix can be any precoding matrix in the first precoding matrix set.

[0184] In this first set of precoding matrices, the precoding matrices are N x 1 matrices, where N is the number of antenna ports of the terminal device (N can also be understood as the number of antennas of the terminal device). This first set of precoding matrices can be called an encryption precoding matrix set or an encryption book set. Encryption can be understood as increasing the density of the directions corresponding to the precoding matrices.

[0185] Where N is a positive integer. For example, N can be 2, or N can be 4, or N can be 8, or N can be 16.

[0186] The first set of precoding matrices includes some or all of the precoding matrices in the second set of precoding matrices.

[0187] In the first example, the first set of precoding matrices may include all the precoding matrices in the second set of precoding matrices.

[0188] In the first example, the first precoding matrix set can be called the enhanced precoding matrix set, or the enhanced codebook set.

[0189] In the second example, the first set of precoding matrices may include some of the precoding matrices in the second set of precoding matrices. For example, the first set of precoding matrices may include Z precoding matrices from the second set of precoding matrices. The specific method for determining the Z precoding matrices can be found in the description of the Z precoding matrices below, and will not be repeated here.

[0190] The second precoding matrix set includes X precoding matrices, where X is determined based on N and the number of phases corresponding to the modulation scheme. X is a positive integer.

[0191] Where X is greater than 4. For example, a modulation scheme with a number of phases less than or equal to 4 can correspond to N greater than 2; or, when N is less than or equal to 2, the modulation scheme with a number of phases greater than 4 can correspond to N greater than 4.

[0192] The phases corresponding to different modulation methods are different. For example, in the case of QPSK modulation, the phases corresponding to QPSK can be [0, π / 2, π, 3π / 2], so the number of phases corresponding to QPSK can be 4. Alternatively, in the case of 8-phase shift keying (PSK) modulation, the phases corresponding to 8PSK can be [0, π / 4, π / 2, 3π / 4, π, 5π / 4, 3π / 2, 7π / 4], so the number of phases corresponding to 8PSK can be 8.

[0193] It is understandable that each phase of the modulation method can correspond to a value of a constellation point.

[0194] In one example, taking the phase of QPSK as [0,π / 2,π,3π / 2], the value of the constellation point corresponding to 0 can be 1, the value of the constellation point corresponding to π / 2 can be j, the value of the constellation point corresponding to π can be -1, and the value of the constellation point corresponding to 3π / 2 can be -j. That is to say, the value of the constellation point corresponding to QPSK can be [1,-1,j,-j].

[0195] In another example, taking the phase of 8PSK as [0,π / 4,π / 2,3π / 4,π,5π / 4,3π / 2,7π / 4], the value of the constellation point corresponding to 0 can be 1, the value of the constellation point corresponding to π / 2 can be j, the value of the constellation point corresponding to π can be -1, the value of the constellation point corresponding to 3π / 2 can be -j, and the value of the constellation point corresponding to π / 4 can be... The value of the constellation point corresponding to 3π / 4 can be... The value of the constellation point corresponding to 5π / 4 can be... The value of the constellation point corresponding to 7π / 4 can be... In other words, the constellation point value corresponding to 8PSK can be

[0196] In the second set of precoding matrices, the elements in the first row of the precoding matrix are 1 (or it can be described as the precoding matrix based on the elements in the first row), and the elements in the second to Nth rows are determined according to the phase corresponding to the modulation scheme.

[0197] Since each phase corresponding to the modulation scheme can correspond to a constellation point value, the elements in rows 2 to N are determined according to the phase corresponding to the modulation scheme. Alternatively, the elements in rows 2 to N can be described as being determined according to the constellation point value corresponding to the modulation scheme. For details, please refer to the description of the second precoding matrix set below; it will not be repeated here.

[0198] Step 502: The network device sends a first instruction message to the terminal device; correspondingly, the terminal device receives the first instruction message from the network device.

[0199] The terminal device can determine the first precoding matrix based on the first instruction information.

[0200] Step 503: The terminal device precodes the signal according to the first precoding matrix.

[0201] For example, the terminal device can multiply the first precoding matrix with the signal to perform signal precoding.

[0202] Furthermore, the terminal device can send pre-coded signals.

[0203] Based on the communication method shown in Figure 5, the terminal device can precode the signal according to the first precoding matrix in the first precoding matrix set, which may include a second precoding matrix set. On one hand, the precoding matrices in the second precoding matrix set can be determined according to the phase corresponding to the modulation scheme, making the directions of the precoding matrices in the second precoding matrix set more dense, thus improving uplink coverage performance. On the other hand, the direction of signal transmission by the terminal device varies in different communication scenarios. Because the directions of the precoding matrices in the second precoding matrix set are more dense, the determined first precoding matrix can better meet the communication needs of the terminal device, improving communication reliability and thus enhancing communication performance.

[0204] Based on the description of the second precoding matrix set in step 501, this application provides two possible designs to determine the second precoding matrix set. In the first possible design, the number X of precoding matrices in the second precoding matrix set can be determined according to the number N of antenna ports of the terminal device and the number of phases corresponding to the modulation method. In the second possible design, the number X of precoding matrices in the second precoding matrix set can be determined according to N, the number of phases corresponding to the modulation method, A, and the size of the first set.

[0205] Where A is a positive integer less than or equal to N / 2. For example, if N is 8, A can be 4, or A can be 2, or A can be 1. Alternatively, if N is 4, A can be 2, or A can be 1.

[0206] The size of the first set can be understood as the number of elements in the first set. The specific method for determining the first set is described below and will not be repeated here.

[0207] The first possible design is described in detail below:

[0208] Optionally, X can be the (N-1)th power of the number of phases corresponding to the modulation scheme. X is a positive integer.

[0209] For example, if N is 2 and the modulation method corresponds to 8 phases, X can be 8; or, if N is 4 and the modulation method corresponds to 8 phases, X can be 8. 3 Alternatively, taking N as 8 and the modulation scheme corresponding to 8 phases as an example, X can be 8. 7 Alternatively, taking N as 16 and the modulation scheme corresponding to 8 phases as an example, X can be 8. 15 Alternatively, taking N as 4 and the modulation method corresponding to 4 phases as an example, X can be 4. 3Alternatively, taking N as 8 and the modulation scheme corresponding to 4 phases as an example, X can be 4. 7 Alternatively, taking N as 16 and the modulation method corresponding to 4 phases as an example, X can be 4. 15 .

[0210] Optionally, the elements in the first row of the precoding matrix in the second precoding matrix set can be 1, and the elements in the k-th row of the precoding matrix in the second precoding matrix set can be determined according to one of the phases corresponding to the modulation scheme; or, the elements in the first row of the precoding matrix in the second precoding matrix set can be 1, and the elements in the k-th row of the precoding matrix in the second precoding matrix set can be the value of one of the constellation points corresponding to the modulation scheme.

[0211] Where k = 2, 3, ..., N.

[0212] For example, taking QPSK modulation as an example, the value of the constellation point corresponding to QPSK can be [1,-1,j,-j]. Assuming N is 4, the element in the first row of the precoding matrix can be 1, the element in the second row can be one of 1, -1, j, or -j, the element in the third row can be one of 1, -1, j, or -j, and the element in the fourth row can be one of 1, -1, j, or -j.

[0213] In this context, elements in different rows of the precoding matrix can be the same or different, without restriction.

[0214] This application provides two possible implementations to determine the second precoding matrix set. In the first possible implementation, the modulation scheme is QPSK; in the second possible implementation, the modulation scheme is 8PSK.

[0215] The first possible implementation is described in detail below:

[0216] In the case of QPSK modulation, the phase corresponding to QPSK can be [0,π / 2,π,3π / 2], and the value of the constellation point corresponding to QPSK can be [1,-1,j,-j].

[0217] Since X is greater than 4, this application provides two possible embodiments to determine the second precoding matrix set corresponding to different N when the modulation scheme is QPSK.

[0218] In a first possible embodiment, taking N=4 as an example, the elements in the first row of the precoding matrix in the second precoding matrix set can be 1, the elements in the second row can be one of 1, -1, j, -j, the elements in the third row can be one of 1, -1, j, -j, and the elements in the fourth row can be one of 1, -1, j, -j. Therefore, the second precoding matrix set can include 64 (i.e., 4...) 3 ) precoding matrices (e.g., precoding matrix 0 to precoding matrix 63).

[0219] For example, precoding matrix 0 in the second precoding matrix set can be Precoding matrix 1 can be Precoding matrix 2 can be Precoding matrix 3 can be Precoding matrix 4 can be Precoding matrix 5 can be Precoding matrix 6 can be Precoding matrix 7 can be The precoding matrix 8 can be Precoding matrix 9 can be …, the precoding matrix 63 can be…

[0220] In a second possible embodiment, taking N=8 as an example, the elements in the first row of the precoding matrix in the second precoding matrix set can be 1; the elements in the second row can be one of 1, -1, j, or -j; the elements in the third row can be one of 1, -1, j, or -j; the elements in the fourth row can be one of 1, -1, j, or -j; the elements in the fifth row can be one of 1, -1, j, or -j; the elements in the sixth row can be one of 1, -1, j, or -j; and the elements in the seventh row can be one of 1, -1, j, or -j. Therefore, the second precoding matrix set can include 16384 (i.e., 4...) 7 ) precoding matrices (e.g., precoding matrix 0 to precoding matrix 16383).

[0221] For example, precoding matrix 0 in the second precoding matrix set can be Precoding matrix 1 can be Precoding matrix 2 can be Precoding matrix 3 can be Precoding matrix 4 can be Precoding matrix 5 can be Precoding matrix 6 can be Precoding matrix 7 can be The precoding matrix 8 can be Precoding matrix 9 can be …, the precoding matrix 16383 can be…

[0222] In the second possible implementation, the modulation scheme can be 8PSK. The phase corresponding to 8PSK can be [0,π / 4,π / 2,3π / 4,π,5π / 4,3π / 2,7π / 4]. Therefore, the values ​​of the constellation points corresponding to 8PSK can be [1,-1,j,-j].

[0223] In the case of 8PSK modulation, this application provides three possible embodiments to determine the second precoding matrix set corresponding to different N.

[0224] In a first possible embodiment, taking N=2 as an example, the elements in the first row of the precoding matrix in the second precoding matrix set can be 1, and the elements in the second row can be 1, -1, j, -j, ... If one of them is true, then the second precoding matrix set can include 8 (i.e., 8... 1 There are 10 precoding matrices (e.g., precoding matrix 0 to precoding matrix 7).

[0225] For example, precoding matrix 0 in the second precoding matrix set can be Precoding matrix 1 can be Precoding matrix 2 can be Precoding matrix 3 can be Precoding matrix 4 can be The precoding matrix 5 can be... Precoding matrix 6 can be Precoding matrix 7 can be

[0226] In a second possible embodiment, taking N=4 as an example, the elements in the first row of the precoding matrix in the second precoding matrix set can be 1, and the elements in each of the second and third rows can be 1, -1, j, -j, ... If one of them is true, then the second precoding matrix set can include 512 (i.e., 8... 3 There are 5 precoding matrices (e.g., precoding matrix 0 to precoding matrix 511).

[0227] For example, precoding matrix 0 in the second precoding matrix set can be Precoding matrix 1 can be Precoding matrix 2 can be Precoding matrix 3 can be Precoding matrix 4 can be Precoding matrix 5 can be Precoding matrix 6 can be Precoding matrix 7 can be The precoding matrix 8 can be Precoding matrix 9 can be Precoding matrix 10 can be Precoding matrix 11 can be Precoding matrix 12 can be Precoding matrix 13 can be Precoding matrix 14 can be …, the precoding matrix 511 can be

[0228] In a third possible embodiment, taking N=8 as an example, the elements in the first row of the precoding matrix in the second precoding matrix set can be 1, and the elements in each row from the second to the seventh row can be 1, -1, j, -j, ... If one of them is true, then the second precoding matrix set can include 2097152 (i.e., 8...). 7 ) precoding matrices (e.g., precoding matrix 0 to precoding matrix 2097151).

[0229] For example, precoding matrix 0 in the second precoding matrix set can be Precoding matrix 1 can be Precoding matrix 2 can be Precoding matrix 3 can be Precoding matrix 4 can be Precoding matrix 5 can be Precoding matrix 6 can be Precoding matrix 7 can be …, the precoding matrix 2097151 can be…

[0230] Based on the first possible design, the elements of the k-th row in the determined precoding matrix can traverse all phases corresponding to the modulation scheme, which can make the directions corresponding to the precoding matrices in the second precoding matrix set more dense, thereby improving uplink coverage performance.

[0231] In the second possible design, the number X of precoding matrices in the second precoding matrix set can be determined based on N, the number of phases corresponding to the modulation scheme, A, and the size of the first set.

[0232] The first set may include one or more phase differences. Optionally, the first set may be determined based on the phase corresponding to the modulation scheme, or the first set may be predefined.

[0233] For example, the first set may include the absolute value of the difference between any two phases corresponding to the modulation scheme. These two phases may be the same phase.

[0234] For example, taking 8PSK modulation as an example, the phase corresponding to QPSK can be [0,π / 4,π / 2,3π / 4,π,5π / 4,3π / 2,7π / 4], and the first set can include {0,π / 4,π / 2,π / 2,3π / 4,π,5π / 4,3π / 2,7π / 4}.

[0235] For example, taking QPSK as the modulation method, the phase corresponding to QPSK can be [0,π / 2,π,3π / 2], and the first set can include {0,π / 2,π,3π / 2}.

[0236] Optionally, the network device may send a fourth indication message to the terminal device; correspondingly, the terminal device may receive the fourth indication message from the network device. The fourth indication message is used to indicate the first set.

[0237] Understandably, when the first set is predefined, the terminal device or network device can directly determine the first set, and then determine the number of precoding matrices in the second precoding matrix set based on the phase difference in the first set. This reduces the workload of the terminal device or network device and lowers transmission overhead. When the first set is determined based on the phase corresponding to the modulation scheme, the first set can be dynamically determined according to the actual communication situation, improving the flexibility and versatility of determining the first set.

[0238] Optionally, X can be the product of (A-1) powers of the number of phases corresponding to the modulation method and the size of the first set, that is, X can be the A power of the number of phases corresponding to the modulation method.

[0239] For example, taking N as 8 and the modulation method corresponding to 4 phases as an example, assuming A is 4 and the size of the first set is 4, we can determine that X can be 256 (i.e., 4). 3 *4 = 256, or, 4 4 =256).

[0240] Optionally, the precoding matrices in the second set of precoding matrices may include the first matrix and the second matrix, both of which are A-row, 1-column matrices.

[0241] The first matrix may include elements from row A of the precoding matrix, and the second matrix may include elements from row A of the precoding matrix excluding those from the first matrix.

[0242] For example, the first matrix may include elements of any row A in the precoding matrix, or the first matrix may include elements of any consecutive rows A in the precoding matrix; similarly, the second matrix may include elements of any row A in the precoding matrix other than the first matrix, or the second matrix may include elements of any consecutive rows A in the precoding matrix other than the first matrix.

[0243] For example, when A is N / 2, the first matrix may include the elements of the first N / 2 rows of the precoding matrix, and the second matrix may include the elements of the last N / 2 rows of the precoding matrix.

[0244] For example, when A is N / 4, the first matrix may include elements from row 1 to row N / 4 of the precoding matrix, and the second matrix may include elements from row (N / 4+1) to row N / 2 of the precoding matrix. Alternatively, the first matrix may include elements from row 1 to row N / 4 of the precoding matrix, and the second matrix may include elements from row (N / 2+1) to row 3N / 4 of the precoding matrix. Alternatively, the first matrix may include elements from row 1 to row N / 4 of the precoding matrix, and the second matrix may include elements from row (3N / 4+1) to row N of the precoding matrix. Alternatively, the first matrix may include elements from row (N / 4+1) to row N / 2 of the precoding matrix, and the second matrix may include elements from row (N / 2+1) to row 3N / 4 of the precoding matrix. Alternatively, the first matrix may include elements from row (N / 4+1) to row (N / 2) of the precoding matrix, and the second matrix may include elements from row (3N / 4+1) to row (N) of the precoding matrix. Alternatively, the first matrix may include elements from row (N / 2+1) to row (3N / 4) of the precoding matrix, and the second matrix may include elements from row (3N / 4+1) to row (N) of the precoding matrix.

[0245] It is understood that the elements included in the first matrix and the elements included in the second matrix can be interchanged. The above is merely an example and does not limit this application. For example, the first matrix may include elements from row 1 to row N / 4 of the precoding matrix, and the second matrix may include elements from row (N / 4+1) to row N / 2 of the precoding matrix. Alternatively, the first matrix may include elements from row (N / 4+1) to row N / 2 of the precoding matrix, and the second matrix may include elements from row 1 to row N / 4 of the precoding matrix.

[0246] Optionally, the precoding matrix may also include a sixth matrix, which may include elements from row A of the precoding matrix other than the first and second matrices. Similarly, the precoding matrix may also include a seventh matrix, and so on; please refer to the description of the sixth matrix for details.

[0247] The sixth matrix may include elements from any row A of the precoding matrix other than the first and second matrices, or the sixth matrix may include elements from any consecutive rows A of the precoding matrix other than the first and second matrices.

[0248] For example, with A being N / 4, the precoding matrix may include a first matrix, a second matrix, a sixth matrix, and a seventh matrix. The first matrix may include elements from row 1 to row N / 4 of the precoding matrix; the second matrix may include elements from row (N / 4+1) to row N / 2 of the precoding matrix; the sixth matrix may include elements from row (N / 2+1) to row 3N / 4 of the precoding matrix; and the seventh matrix may include elements from row (3N / 4+1) to row N of the precoding matrix.

[0249] Alternatively, the first matrix may include elements from row 1 to row N / 4 of the precoding matrix, the second matrix may include elements from row (N / 2+1) to row 3N / 4 of the precoding matrix, the sixth matrix may include elements from row (N / 4+1) to row N / 2 of the precoding matrix, and the seventh matrix may include elements from row (3N / 4+1) to row N of the precoding matrix.

[0250] Alternatively, the first matrix may include elements from row 1 to row N / 4 of the precoding matrix, the second matrix may include elements from row (3N / 4+1) to row N of the precoding matrix, the sixth matrix may include elements from row (N / 4+1) to row N / 2 of the precoding matrix, and the seventh matrix may include elements from row (N / 2+1) to row 3N / 4 of the precoding matrix.

[0251] It is understood that the elements included in the sixth matrix and the elements included in the seventh matrix can be interchanged. The above is merely an example and does not impose any limitations on this application. For example, the sixth matrix may include elements from row (N / 2+1) to row 3N / 4 of the precoding matrix, and the seventh matrix may include elements from row (3N / 4+1) to row N of the precoding matrix. Alternatively, the sixth matrix may include elements from row (3N / 4+1) to row N of the precoding matrix, and the seventh matrix may include elements from row (N / 2+1) to row 3N / 4 of the precoding matrix.

[0252] The absolute difference between the phase of each element in the first matrix and the phase of each element in the second matrix is ​​the first phase difference. Similarly, the absolute difference between the phase of each element in the first matrix and the phase of each element in the sixth matrix is ​​the first phase difference.

[0253] For example, the absolute value of the difference between the phase corresponding to the element in row a of the first matrix and the phase corresponding to the element in row a of the second matrix can be the first phase. Alternatively, the absolute value of the difference between the phase corresponding to the element in row a of the first matrix and the phase corresponding to the element in row A-a+1 of the second matrix can be the first phase. a = 1, 2, ..., A.

[0254] Similarly, the absolute value of the difference between the phase corresponding to the element in row a of the first matrix and the phase corresponding to the element in row a of the sixth matrix can be considered the first phase. Alternatively, the absolute value of the difference between the phase corresponding to the element in row a of the first matrix and the phase corresponding to the element in row A-a+1 of the sixth matrix can be considered the first phase. a = 1, 2, ..., A.

[0255] It is understandable that each element in a row of the first matrix can correspond to an element in a row of the second matrix. For example, assuming both the first and second matrices have 4 rows, an element in the first row of the first matrix can correspond to an element in any row of the second matrix (e.g., an element in the first row of the first matrix can correspond to an element in the first row of the second matrix, or an element in the first row of the first matrix can correspond to an element in the second row of the second matrix, or an element in the first row of the first matrix can correspond to an element in the third row of the second matrix, or an element in the first row of the first matrix can correspond to an element in the fourth row of the second matrix), and an element in the second row of the first matrix can correspond to an element in the second matrix. The element in the x-th row is the element in the second matrix, where x is any row in the second matrix other than the row in the first matrix that corresponds to the element in the first row (e.g., if the element in the first row of the first matrix corresponds to the element in the first row of the second matrix, then the element in the second row of the first matrix can correspond to the element in the second row of the second matrix, or the element in the second row of the first matrix can correspond to the element in the third row of the second matrix, or the element in the second row of the first matrix can correspond to the element in the fourth row of the second matrix), and so on. This way, we can determine the element in the second matrix that corresponds to the element in each row of the first matrix.

[0256] The relationship between the first matrix and the sixth matrix can be referred to the above description of the relationship between the first matrix and the second matrix, and will not be repeated here.

[0257] The first phase difference can be included in the first set. The first set can be referred to the description of the first set above, and will not be repeated here.

[0258] It is understood that the first set may include multiple phase differences, and the first phase difference may be one of these multiple phase differences. At least two of the multiple precoding matrices may have different first phase differences. For example, taking a first set that includes four phase differences (such as phase difference 0, phase difference 1, phase difference 2, and phase difference 3), assume that the second precoding matrix set can include precoding matrix 0, precoding matrix 1, precoding matrix 2, and precoding matrix 3. In precoding matrix 0, the absolute value of the difference between the phase corresponding to an element in a row of the first matrix and the phase corresponding to an element in a row of the second matrix is ​​phase difference 0 (at this time, the first phase difference is phase difference 0); in precoding matrix 1, the absolute value of the difference between the phase corresponding to an element in a row of the first matrix and the phase corresponding to an element in a row of the second matrix is ​​phase difference 1 (at this time, the first phase difference is phase difference 1); in precoding matrix 2, the absolute value of the difference between the phase corresponding to an element in a row of the first matrix and the phase corresponding to an element in a row of the second matrix is ​​phase difference 2 (at this time, the first phase difference is phase difference 2); in precoding matrix 3, the absolute value of the difference between the phase corresponding to an element in a row of the first matrix and the phase corresponding to an element in a row of the second matrix is ​​phase difference 3 (at this time, the first phase difference is phase difference 3).

[0259] The following uses the first and second matrices as examples to illustrate how the first and second matrices are determined. This method can also be applied to the determination of the sixth and seventh matrices, as well as other matrices included in the precoding matrix, which will not be elaborated upon in this application.

[0260] In determining the precoding matrix, the elements in the first row of the first matrix can be set to 1, and the elements in each row from the second row to the Ath row can be determined according to one phase corresponding to the modulation scheme. Then, the second matrix can be determined according to the first phase difference and the first matrix (that is, the sum of the phase corresponding to the element in the first row of the first matrix and the first phase difference is the phase corresponding to the element in the second row of the second matrix, or the difference between the phase corresponding to the element in the first row of the first matrix and the first phase difference is the phase corresponding to the element in the second row of the second matrix). Furthermore, the precoding matrix can be determined according to the first matrix and the second matrix.

[0261] The determination of the first matrix can refer to the description of the determination of the precoding matrix in the first possible design above. That is, N can be replaced with A to determine multiple first matrices, which will not be elaborated here.

[0262] In this application, taking the absolute value of the difference between the phase corresponding to the element in the a-th row of the first matrix and the phase corresponding to the element in the a-th row of the second matrix as the first phase difference as an example, two possible implementations are provided to determine the second precoding matrix set corresponding to different N:

[0263] In the first possible implementation, N can be 4, and the precoding matrices in the second set of precoding matrices can include the first matrix and the second matrix, both of which have 2 rows.

[0264] In one example, taking QPSK modulation as an example, the phase corresponding to QPSK can be [0,π / 2,π,3π / 2]. Therefore, the first set can include {0,π / 2,π,3π / 2}. The constellation point value corresponding to QPSK can be [1,-1,j,-j]. The element in the first row of the first matrix can be 1, and the element in the second row can be one of 1, -1, j, or -j. Therefore, the first matrix 0 can be... The first matrix 1 can be... The first matrix 2 can be... The first matrix 3 can be... When the first phase difference is 0, the second matrix 0 corresponding to the first matrix 0 can be... Then, the precoding matrix 0 can be The second matrix 1 corresponding to the first matrix 1 can be... Then the precoding matrix 1 can be The second matrix 2 corresponding to the first matrix 2 can be... Then the precoding matrix 2 can be The second matrix 3 corresponding to the first matrix 3 can be... Then the precoding matrix 3 can be Similarly, when the first phase difference is π / 2, the second matrix 0 corresponding to the first matrix 0 can be... Then, the precoding matrix 0 can be The second matrix 1 corresponding to the first matrix 1 can be... Then the precoding matrix 1 can be The second matrix 2 corresponding to the first matrix 2 can be... Then the precoding matrix 2 can be The second matrix 3 corresponding to the first matrix 3 can be... Then the precoding matrix 3 can be Similarly, when the first phase difference is π, the second matrix corresponding to the first matrix can be determined, and the precoding matrix can be determined; when the first phase difference is 3π / 2, the second matrix corresponding to the first matrix can be determined, and the precoding matrix can be determined; thus, all precoding matrices in the second precoding matrix set can be determined.

[0265] In another example, taking 8PSK modulation as an example, the phase corresponding to 8PSK can be [0,π / 4,π / 2,3π / 4,π,5π / 4,3π / 2,7π / 4]. Therefore, the first set can include {0,π / 4,π / 2,π / 2,3π / 4,π,5π / 4,3π / 2,7π / 4}, and the constellation point values ​​corresponding to 8PSK can be [1,-1,j,-j,]. The elements in the first row of the first matrix can be 1, and the elements in the second row can be 1, -1, j, -j, ... If one of them is true, then the first matrix 0 can be... The first matrix 1 can be... The first matrix 2 can be... The first matrix 3 can be... The first matrix 4 can be... The first matrix 5 can be... The first matrix 6 can be... The first matrix 7 can be... The second matrix corresponding to the first matrix when the first phase difference is 0, π / 4, π / 2, π / 2, 3π / 4, π, 5π / 4, 3π / 2, or 7π / 4 can be determined sequentially, and the precoding matrix can be determined. The specific determination method can be referred to the example above. Thus, all precoding matrices in the second precoding matrix set can be determined.

[0266] Based on the first possible implementation, when N is 4 and A is 2, the precoding matrix in the second precoding matrix set corresponding to N is 4 can include a first matrix and a second matrix. The determination of the first matrix is ​​the same as the determination of the precoding matrix in the second precoding matrix set corresponding to N is 2. The second matrix can be determined based on the first matrix and the first phase difference.

[0267] In the second possible implementation, N can be 8, and the precoding matrices in the second precoding matrix set can include the first matrix and the second matrix, both of which have 4 rows. Alternatively, the precoding matrices in the second precoding matrix set can include the first matrix, the second matrix, the sixth matrix, and the seventh matrix, all of which have 2 rows.

[0268] The precoding matrices in the second set of precoding matrices include the first matrix and the second matrix. The method for determining the first matrix and the second matrix can be referred to in the first possible implementation, which will not be elaborated here.

[0269] The precoding matrices in the second precoding matrix set may include the first matrix, the second matrix, the sixth matrix, and the seventh matrix. This application proposes a possible embodiment, taking QPSK modulation as an example. The phase corresponding to QPSK can be [0, π / 2, π, 3π / 2]. Therefore, the first set may include {0, π / 2, π, 3π / 2}. The constellation point values ​​corresponding to QPSK can be [1, -1, j, -j]. The elements in the first row of the first matrix can be 1, and the elements in the second row can be one of 1, -1, j, or -j. Therefore, the first matrix 0 can be... The first matrix 1 can be... The first matrix 2 can be... The first matrix 3 can be... When the first phase difference is 0, the second matrix 0 corresponding to the first matrix 0 can be... The sixth matrix 0 corresponding to the first matrix 0 can be... The seventh matrix 0 corresponding to the first matrix 0 can be... Then, the precoding matrix 0 can be The second matrix 1 corresponding to the first matrix 1 can be... The sixth matrix 1 corresponding to the first matrix 1 can be... The seventh matrix 1 corresponding to the first matrix 1 can be... Then the precoding matrix 1 can be The second matrix 2 corresponding to the first matrix 2 can be... The sixth matrix 2 corresponding to the first matrix 2 can be... The seventh matrix 2 corresponding to the first matrix 2 can be... Then the precoding matrix 2 can be The second matrix 3 corresponding to the first matrix 3 can be... The sixth matrix 3 corresponding to the first matrix 3 can be... The seventh matrix 3 corresponding to the first matrix 3 can be... Then the precoding matrix 3 can be Similarly, when the first phase difference is π / 2, the corresponding second, sixth, and seventh matrices of the first matrix can be determined, and the precoding matrix can be determined; when the first phase difference is π, the corresponding second, sixth, and seventh matrices of the first matrix can be determined, and the precoding matrix can be determined; when the first phase difference is 3π / 2, the corresponding second, sixth, and seventh matrices of the first matrix can be determined, and the precoding matrix can be determined; thus, all precoding matrices in the second precoding matrix set can be determined. Furthermore, different first, second, sixth, and seventh matrices can be determined based on different modulation schemes, and the precoding matrix can be determined, thus determining all precoding matrices in the second precoding matrix set.

[0270] Based on the second possible implementation, when N is 8 and A is 4, the precoding matrices in the second precoding matrix set corresponding to N=8 can include a first matrix and a second matrix. The determination of the first matrix is ​​the same as that of the precoding matrices in the second precoding matrix set corresponding to N=4, and the second matrix is ​​determined based on the first matrix and the first phase difference. Alternatively, when N is 8 and A is 2, the precoding matrices in the second precoding matrix set corresponding to N=8 can include a first matrix, a second matrix, a sixth matrix, and a seventh matrix. The determination of the first matrix is ​​the same as that of the precoding matrices in the second precoding matrix set corresponding to N=2, and the second, sixth, and seventh matrices can be determined based on the first matrix and the first phase difference.

[0271] Based on the second possible design, the directions of the precoding matrices in the determined second precoding matrix set can be made as uniform as possible, which can improve uplink coverage performance. In addition, the second possible design results in a smaller number of precoding matrices in the determined second precoding matrix set, which can reduce the storage requirements of the second precoding matrix set.

[0272] Based on the above description of the second precoding matrix set, the first precoding matrix set may include all the precoding matrices in the second precoding matrix set; or, the first precoding matrix set may include a portion of the precoding matrices in the second precoding matrix set.

[0273] The following describes the first precoding matrix and the first indication information, taking into account all precoding matrices in the first precoding matrix set, including the second precoding matrix set:

[0274] Optionally, the first set of precoding matrices may also include a third set of precoding matrices.

[0275] The third set of precoding matrices includes partially phase-intervention coding matrices; one or more elements in the partially phase-intervention coding matrices are 0.

[0276] In the first example, taking N=2 as an example, the third precoding matrix set can include and

[0277] In the second example, taking N as 4, the third precoding matrix set can include and

[0278] Understandably, partial phase interferometry (PPI) coding matrices are used to reduce the requirements on the antenna capabilities of terminal devices (e.g., when the antenna capabilities of a terminal device are poor, the correlation between different antennas is high, and simultaneous signal transmission can lead to strong interference). By sacrificing some of the spatial diversity gain brought by multiple antennas and obtaining more independent channels, communication reliability can be improved. For example, using a PPI coding matrix as... For example, terminal devices can reduce signal interference and improve communication reliability by discarding three antennas and transmitting signals through one antenna.

[0279] The network device can determine the first precoding matrix from the first precoding matrix set based on channel state information. Furthermore, the network device can indicate the first precoding matrix to the terminal device through first indication information.

[0280] Optionally, the first indication information is used to indicate the index of the first precoding matrix in the first set of precoding matrices; or, the first indication information is used to indicate the index of the first precoding matrix in a subset of precoding matrices. This application provides two possible implementations:

[0281] In a first possible implementation, the first indication information is used to indicate the index of the first precoding matrix in the first precoding matrix set (or it can be described as the identifier of the first precoding matrix in the first precoding matrix set).

[0282] The number of bits occupied by the first indication information can be determined based on the number of precoding matrices (e.g., M) in the first precoding matrix set. For example, the number of bits occupied by the first indication information can be... This indicates rounding up. For example, if M is 64, the first indication information can occupy 6 bits.

[0283] For example, the first indication information can indicate the index of the first precoding matrix (or can be described as the identifier of the first precoding matrix). Taking a first precoding matrix set including 10 precoding matrices (such as precoding matrix 0 to precoding matrix 63) as an example, the first indication information can occupy 6 bits. By setting the bit value to 000000, representing the index of precoding matrix 0, the terminal device can determine that the first precoding matrix is ​​precoding matrix 0; by setting the bit value to 00001, representing the index of precoding matrix 1, the terminal device can determine that the first precoding matrix is ​​precoding matrix 1; by setting the bit value to 000010, representing the index of precoding matrix 2, the terminal device can determine that the first precoding matrix is ​​precoding matrix 2; ...; by setting the bit value to 111111, representing the index of precoding matrix 63, the terminal device can determine that the first precoding matrix is ​​precoding matrix 63.

[0284] Based on the first possible implementation, the first indication information can directly indicate the index of the first precoding matrix in the first precoding matrix set. That is, the terminal device can determine the first precoding matrix through a single-level indication. In the case of two-level indication, the update cycle of the second indication information is relatively long. The first indication information can indicate the precoding matrix in a subset of precoding matrices for a period of time, which is equivalent to the precoding matrices in the first precoding matrix set becoming sparse. However, in the case of single-level indication, the first indication information can always indicate the precoding matrix in the first precoding matrix set, which can improve transmission performance and uplink coverage performance.

[0285] In a second possible implementation, the first indication information can indicate the index of the first precoding matrix within a subset of the precoding matrix. Furthermore, the network device can also send second indication information to the terminal device, indicating the subset of the precoding matrix; correspondingly, the terminal device can receive the second indication information from the network device and determine the subset of the precoding matrix based on the second indication information.

[0286] The number of bits occupied by the first indication information can be determined based on the number of precoding matrices (e.g., m) in the precoding matrix subset. For example, the number of bits occupied by the first indication information can be... This indicates rounding up. For example, if m is 8, the first indication information can occupy 3 bits.

[0287] The second indication information is used to indicate a subset of the precoding matrix.

[0288] In one example, the second indication information can indicate the index of a precoding matrix subset. Taking the existence of four precoding matrix subsets (precoding matrix subset 0, precoding matrix subset 1, precoding matrix subset 2, and precoding matrix subset 3) as an example, the second indication information can occupy two bits. The bit value can be set to 00 to indicate the index of the precoding matrix subset 0; the bit value can be set to 01 to indicate the index of the precoding matrix subset 1; the bit value can be set to 10 to indicate the index of the precoding matrix subset 2; and the bit value can be set to 11 to indicate the index of the precoding matrix subset 3.

[0289] In another example, the second indication information can be a third bitmap, where each bit represents a subset of the precoding matrix. For example, if there are four subsets of the precoding matrix (subset 0, subset 1, subset 2, and subset 3), the bitmap can occupy four bits, with the high bit being the start bit. Setting the bitmap to 1000 indicates subset 0; setting it to 0100 indicates subset 1; setting it to 0010 indicates subset 2; and setting it to 0001 indicates subset 3.

[0290] Optionally, the second indication information may be located in an RRC message; or, the second indication information may be located in a system message.

[0291] Optionally, the second indication information may be located in different messages (e.g., the second indication information may be located in an RRC message and the first indication information may be located in a DCI), or the second indication information may be located in the same message (e.g., the first indication information and the second indication information may be located in an RRC message; or, the first indication information and the second indication information may be located in a DCI).

[0292] Based on the second possible implementation, the terminal device can determine the precoding matrix subset through the second indication information and indicate the index of the first precoding matrix in the precoding matrix subset through the first indication information. That is, the first precoding matrix can be determined through a two-level indication method, which can reduce the number of bits occupied by the first indication information and reduce transmission overhead. At the same time, when the first indication information is located in DCI, the modification of the first indication information can be avoided as much as possible, thereby avoiding the addition of new DCI types as much as possible.

[0293] Based on the second possible implementation, a specific example of the first indication information indicating the first precoding matrix can be referred to in the description of the first indication information in the first possible implementation above, and will not be repeated here.

[0294] Based on the above description of the precoding matrix subset, this application provides three possible implementations for determining the precoding matrix subset:

[0295] In one possible implementation, the first set of precoding matrices can be divided into multiple subsets of precoding matrices. The number of precoding matrices in each subset can be less than or equal to 2^K (i.e., 2^K). K K is equal to the number of bits occupied by the first indication information (at this time, the first indication information indicates the first precoding matrix in the precoding matrix subset).

[0296] In the first example, the precoding matrices in the first precoding matrix set can be evenly divided. Taking an example where the first precoding matrix set includes M precoding matrices (e.g., precoding matrix 0 to precoding matrix M-1), and assuming the first indication information occupies K bits, it can be determined that... A subset of precoded matrices.

[0297] For example, K precoding matrices can be sequentially determined from the first set of precoding matrices, and the subset 0 of precoding matrices can include precoding matrices 0 to 2. K -1, Precoding matrix subset 1 can include precoding matrix K to precoding matrix 2 K+1 -1, Precoding matrix subset 2 may include precoding matrix 2 K+1 To the precoding matrix 3*2 K -1, ..., subsets of the precoding matrix It can include a precoding matrix To the precoding matrix M-1.

[0298] Among them, in the precoding matrix subset The number of precoding matrices in the array is less than 2. K In the case of a subset of the precoding matrix 1 can include a precoding matrix To the precoding matrix M-1; or, a subset of the precoding matrix. It can include the precoding matrix Based on the precoding matrix M-1, it can also include one or more precoding matrices from 0 to M-1, so that the precoding matrix subset The number of precoding matrices in the array can be 2. K .

[0299] For example, K precoding matrices can be determined from the first set of precoding matrices in reverse order. Precoding matrix subset 0 can include precoding matrices M-1 to M-2. K Precoding matrix subset 1 may include precoding matrix M-2 K -1 to precoding matrix M-2 K+1 Precoding matrix subset 2 may include precoding matrix M-2 K+1 -1 to the precoding matrix M-3*2 K ..., subsets of precoding matrices It can include a precoding matrix To precoding matrix 0.

[0300] Among them, in the precoding matrix subset When the number of precoding matrices in a dataset is less than K, the subset of precoding matrices It can include a precoding matrix Up to precoding matrix 0; or, a subset of the precoding matrix. It can include the encoding matrix M- Based on precoding matrix 0, it can also include one or more of precoding matrices from precoding matrix 0 to precoding matrix K-1, so that the precoding matrix subset The number of precoding matrices in the array can be 2. K .

[0301] Based on the first example, the precoding matrix subset can be determined according to the number of precoding matrices in the first precoding matrix set and the number of bits occupied by the first indication information. The number of precoding matrices in different precoding matrix subsets should be as similar as possible, which can simplify the implementation of the precoding matrix subset.

[0302] In the second example, the precoding matrices in the first set of precoding matrices can be divided according to the beam angle (also known as beam direction) corresponding to the precoding matrix. For example, precoding matrices corresponding to beam angles located in the same preset interval can be divided into the same subset of precoding matrices, and different preset intervals can correspond to different subsets of precoding matrices.

[0303] For example, to determine F preset intervals (such as preset interval 0 to preset interval F-1), different preset intervals can correspond to a subset of precoding matrices. The subset of precoding matrices can be determined based on the preset interval in which the beam angle corresponding to each precoding matrix in the first set of precoding matrices is located. For instance, assuming the beam angle corresponding to precoding matrix 0 is located in preset interval 0, it can be determined that precoding matrix subset 0 includes coding matrix 0; or, assuming the beam angle corresponding to precoding matrix 1 is located in preset interval 1, it can be determined that precoding matrix subset 1 includes coding matrix 1; assuming the beam angle corresponding to precoding matrix 2 is located in preset interval F-1, it can be determined that precoding matrix subset F-1 includes coding matrix 2; and so on, F subsets of precoding matrices can be determined.

[0304] Understandably, each element in the precoding matrix is ​​used to weight the corresponding transmitting port. Different ports have different weighting values. Since the precoding matrix is ​​normalized, the weighting values ​​will cause the electromagnetic waves transmitted by different transmitting ports to have different phases. This results in different peak and trough positions for the composite wave after the superposition of multiple electromagnetic waves emitted by multiple transmitting ports. The angle between the direction corresponding to the strongest peak after superposition and the normal vector of the antenna panel can be called the beam angle. In other words, the precoding matrix weights multiple transmitting ports, causing multiple transmitting ports to transmit multiple electromagnetic waves, and the angle between the direction corresponding to the strongest peak after superposition and the normal vector of the antenna panel is called the beam angle.

[0305] Based on the second example, multiple subsets of precoding matrices can be determined from the first set of precoding matrices according to the beam angle corresponding to the precoding matrix, so that the directions corresponding to the precoding matrices belonging to the same set of precoding matrices are similar. When determining the first precoding matrix, the network device can roughly determine the subset of precoding matrices in which the first precoding matrix is ​​located by combining the orientation of the terminal device, which can improve the accuracy of determining the first precoding matrix and thus improve the reliability of communication.

[0306] Optionally, when determining the preset interval, it can be ensured as much as possible that the number of precoding matrices corresponding to the beam angles located in the preset interval is less than or equal to the number of bits occupied by the first indication information (at this time, the first indication information indicates the first precoding matrix in the subset of precoding matrices).

[0307] In a second possible implementation, the subset of precoding matrices may include C precoding matrices from the second set of precoding matrices. The angle between each of the C precoding matrices and the fifth matrix is ​​the sum of the first angle and one of one or more angle intervals.

[0308] The fifth matrix can be any precoding matrix from the second set of precoding matrices. For example, with N=4, the fifth matrix could be... Alternatively, taking N=8 as an example, the fifth matrix can be...

[0309] The first included angle can also be 0, or it can be the minimum angle between each precoding matrix (excluding the fifth matrix) and the fifth matrix in the second precoding matrix set.

[0310] It is understandable that there may be one or more precoding matrices that share the same angle with the fifth matrix. For example, taking the second set of precoding matrices as including M precoding matrices, the angle between precoding matrix 0 and the fifth matrix can be angle 0, and the angle between precoding matrix 1 and the fifth matrix can also be angle 0; or, the angle between precoding matrix 2 and the fifth matrix can be angle 1, and the angle between precoding matrix 3 and the fifth matrix can also be angle 2.

[0311] The included angle interval can be predefined, or it can be determined based on the angle between each precoding matrix in the second precoding matrix set and the fifth matrix. For example, the included angles between each precoding matrix in the second precoding matrix set and the fifth matrix can be arranged from smallest to largest (or from largest to smallest), and the arranged included angles can be divided into X groups. The included angle interval can be the absolute value of the difference between the i-th included angle in any two groups. For example, taking group 0 which includes angles 0, 1, and 2, group 1 which includes angles 3, 4, and 5, and group 3 which includes angles 6, 7, and 8 as examples, the angle interval 0 can be determined to be the absolute value of the difference between angle 0 and angle 3 (or the absolute value of the difference between angle 1 and angle 4, or the absolute value of the difference between angle 2 and angle 5); the angle interval 1 can be determined to be the absolute value of the difference between angle 0 and angle 6 (or the absolute value of the difference between angle 1 and angle 7, or the absolute value of the difference between angle 2 and angle 8); the angle interval 2 can be determined to be the absolute value of the difference between angle 3 and angle 6 (or the absolute value of the difference between angle 4 and angle 7, or the absolute value of the difference between angle 5 and angle 8).

[0312] For example, taking a first precoding matrix set comprising M precoding matrices (e.g., precoding matrix 0 to precoding matrix M-1), the angle between precoding matrix 0 and the fifth matrix can be angle 0, the angle between precoding matrix 1 and the fifth matrix can be angle 1, the angle between precoding matrix 2 and the fifth matrix can be angle 2, ..., and the angle between precoding matrix M-1 and the fifth matrix can be angle M-1. Assuming angle 0 is the minimum value and there are three angle intervals (angle interval 0, angle interval 1, and angle interval 2), then the first angle can be determined to be angle 0. The precoding matrix subset can include the precoding matrix corresponding to the sum of the first angle (i.e., angle 0) and each angle interval. For example, taking the sum of angle 0 and angle interval 0 as angle 4, the sum of angle 0 and angle interval 1 as angle 7, and the sum of angle 0 and angle interval 2 as angle 10, we can determine that the precoding matrix corresponding to angle 4 is precoding matrix 4, the precoding matrix corresponding to angle 7 is precoding matrix 7, and the precoding matrix corresponding to angle 10 is precoding matrix 10. Then, the precoding matrix subset can include precoding matrix 4, precoding matrix 7, and precoding matrix 10.

[0313] Based on the second possible implementation, the terminal device can determine C precoding matrices from the second precoding matrix set as a subset of precoding matrices. Since the angle between each of the C precoding matrices and the fifth matrix is ​​the sum of the first angle and one of the angle intervals, the directions corresponding to the C precoding matrices can be made as uniform as possible, which can improve uplink coverage performance.

[0314] In the third possible implementation, the precoding matrix subset may include a third matrix and a fourth matrix. Both the third and fourth matrices are B-row, 1-column matrices.

[0315] Where B is a positive integer less than or equal to N / 2. For example, if N is 8, B can be 4, or B can be 2, or B can be 1. Alternatively, if N is 4, B can be 2, or B can be 1.

[0316] The third matrix may include elements from row B of the precoding matrix, and the fourth matrix may include elements from row B of the precoding matrix excluding the third matrix.

[0317] The third matrix can be described in the same way as the first matrix above; that is, A can be replaced with B, which will not be elaborated here.

[0318] The fourth matrix can be described in the same way as the second matrix above; that is, A can be replaced with B, which will not be elaborated here.

[0319] It is understood that the elements included in the third matrix and the elements included in the fourth matrix can be interchanged. The above is merely an example and does not limit this application. For example, the third matrix may include elements from row 1 to row N / 4 of the precoding matrix, and the fourth matrix may include elements from row (N / 4+1) to row N / 2 of the precoding matrix. Alternatively, the third matrix may include elements from row (N / 4+1) to row N / 2 of the precoding matrix, and the fourth matrix may include elements from row 1 to row N / 4 of the precoding matrix.

[0320] Optionally, the precoding matrix may also include an eighth matrix, which may include elements of row B of the precoding matrix other than the third and fourth matrices.

[0321] The eighth matrix can be described in the same way as the sixth matrix above; that is, B can be replaced with A, which will not be elaborated here.

[0322] It is understandable that the precoding matrix may also include a ninth matrix, ..., and so on. For details, please refer to the description of the eighth matrix, which will not be repeated here.

[0323] The absolute value of the difference between the phase corresponding to each element in the third matrix and the phase corresponding to each element in the fourth matrix is ​​the second phase difference; similarly, the absolute value of the difference between the phase corresponding to each element in the third matrix and the phase corresponding to each element in the eighth matrix is ​​the second phase difference.

[0324] For example, the absolute value of the difference between the phase corresponding to the element in row b of the third matrix and the phase corresponding to the element in row b of the fourth matrix can be the second phase. Alternatively, the absolute value of the difference between the phase corresponding to the element in row b of the third matrix and the phase corresponding to the element in row B-b+1 of the fourth matrix can be the second phase. b = 1, 2, ..., B.

[0325] Alternatively, the absolute value of the difference between the phase corresponding to the element in row b of the third matrix and the phase corresponding to the element in row b of the eighth matrix can be considered the second phase. Alternatively, the absolute value of the difference between the phase corresponding to the element in row b of the third matrix and the phase corresponding to the element in row B-b+1 of the eighth matrix can be considered the second phase.

[0326] Optionally, the second phase difference can be predefined; or, the second phase difference can be determined according to the phase corresponding to the modulation method, without restriction.

[0327] For example, the second phase difference can be the absolute value of the difference between any two phases corresponding to the modulation scheme. These two phases can also be the same phase. For instance, taking QPSK modulation as an example, the phases corresponding to QPSK can be [0, π / 2, π, 3π / 2]. The difference between any two phases can be 0, π / 2, π, or 3π / 2. Therefore, the second phase difference can be one of 0, π / 2, π, or 3π / 2.

[0328] Optionally, the network device may send a fifth indication message to the terminal device; correspondingly, the terminal device may receive the fifth indication message from the network device, which is used to indicate the second phase difference.

[0329] Understandably, when the second phase difference is predefined, the terminal device or network device can directly determine the second phase difference, and then determine the precoding matrix based on the second phase difference. This reduces the workload of the terminal device or network device and lowers transmission overhead. When the second phase difference is determined according to the phase corresponding to the modulation scheme, the second phase difference can be dynamically determined according to the actual communication situation, improving the flexibility and versatility of determining the second phase difference.

[0330] It is understandable that the second phase difference is the same for different precoding matrices in a precoding subset. For example, taking a precoding subset including precoding matrix 0 and precoding matrix 1 as an example, the absolute value of the difference between the phase corresponding to the element in the third row of the third matrix and the phase corresponding to the element in the fourth row of the fourth matrix in precoding matrix 0 is the second phase difference, and the absolute value of the difference between the phase corresponding to the element in the third row of the third matrix and the phase corresponding to the element in the fourth row of the fourth matrix in precoding matrix 1 is the second phase difference.

[0331] The following uses the third and fourth matrices as examples to illustrate how the third and fourth matrices are determined. This method can also be applied to the determination of the eighth matrix, the ninth matrix, and other matrices included in the precoding matrix, which will not be elaborated upon in this application.

[0332] In determining the precoding matrix, the elements in the first row of the third matrix can be set to 1, and the elements in each row from the second row to the B row can be determined according to one phase of the phase corresponding to the modulation scheme. Then, the fourth matrix can be determined according to the second phase difference. Furthermore, the precoding matrix can be determined according to the third matrix and the fourth matrix.

[0333] The determination of the third matrix can be referred to the above description of the determination of the first matrix. That is, A can be replaced with B to determine multiple third matrices, which will not be elaborated here.

[0334] The determination of the fourth matrix can be made with reference to the description of the determination of the second matrix above. That is, the first phase difference can be replaced with the second phase difference, and A can be replaced with B to determine multiple fourth matrices, which will not be elaborated here.

[0335] Based on the third possible implementation, the terminal device or network device can determine the third and fourth matrices according to the second phase difference, and then determine the precoding matrix in the precoding matrix subset. This can make the corresponding directions of the precoding matrix in the precoding matrix subset as uniform as possible, which can improve uplink coverage performance.

[0336] Among them, the precoding matrix subset in the second possible implementation and the precoding matrix subset in the third possible implementation can be called the basic codebook set, or the basic precoding matrix subset.

[0337] Understandably, when the first precoding matrix set includes all precoding matrices in the second precoding matrix set, the number of precoding matrices in the first precoding matrix set is large. Using the first indication information to indicate the first precoding matrix in the first precoding matrix set may increase the number of bits occupied by the first indication information, significantly impacting the communication protocol and increasing the signaling overhead of network devices. For example, when the first indication information is TPMI, the number of bits occupied by TPMI is fixed. If the first precoding matrix in the first precoding matrix set is indicated through TPMI, the number of bits occupied by TPMI needs to be increased, increasing the implementation complexity. Therefore, if the first indication information is used to indicate the first precoding matrix in a subset of precoding matrices, the subset can be indicated by adding second indication information. The number of bits occupied by the first indication information can remain unchanged, simplifying the implementation and reducing its complexity.

[0338] Furthermore, a communication system contains multiple terminal devices with varying capabilities. For example, one or more terminal devices may support precoding signals using precoding matrices from a fourth precoding matrix set, where the number of precoding matrices is less than the number of precoding matrices in a second precoding matrix set. For different terminal devices, the network device can indicate the first precoding matrix using first indication information. That is, the network device can indicate the first precoding matrix in the fourth precoding matrix set using first indication information (such as TPMI), or it can indicate the first precoding matrix in the first precoding matrix set using first indication information. Therefore, a two-level indication approach can be used to keep the number of bits occupied by the first indication information constant, thereby better supporting terminal devices with different capabilities.

[0339] For example, when N is 2, the fourth precoding matrix set can be the precoding matrix set shown in Table 1; when N is 3, the fourth precoding matrix set can be the precoding matrix set shown in Table 2; and when N is 8, the fourth precoding matrix set can be the precoding matrix set shown in Table 3.

[0340] Optionally, before receiving the first indication information, the terminal device may send its capability information to the network device, as shown in Figure 6:

[0341] Step 601: The terminal device sends its capability information to the network device; correspondingly, the network device receives the capability information from the terminal device.

[0342] The capability information indicates whether the terminal device supports precoding the signal using precoding matrices from the first precoding matrix set. Alternatively, the capability information can be described as indicating whether the terminal device supports precoding the signal using precoding matrices from the first precoding matrix set.

[0343] In one example, taking capability information occupying one bit as an example, the bit value can be set to 1 to indicate that the terminal device supports precoding the signal using precoding matrices from the first precoding matrix set; the bit value can be set to 0 to indicate that the terminal device does not support precoding the signal using precoding matrices from the first precoding matrix set. Alternatively, the bit value can be set to 0 to indicate that the terminal device supports precoding the signal using precoding matrices from the first precoding matrix set; the bit value can be set to 1 to indicate that the terminal device does not support precoding the signal using precoding matrices from the first precoding matrix set.

[0344] In another example, if the terminal device sends capability information, the network device can determine that the terminal device supports precoding the signal using precoding matrices from the first precoding matrix set; if the terminal device does not send capability information, the network device can determine that the terminal device does not support precoding the signal using precoding matrices from the first precoding matrix set. When the terminal device sends capability information, taking the example that capability information occupies one bit, the bit value can be set to 1 to indicate that the terminal device supports precoding the signal using precoding matrices from the first precoding matrix set; or, the bit value can be set to 0 to indicate that the terminal device supports precoding the signal using precoding matrices from the first precoding matrix set.

[0345] Step 602: The network device determines the first instruction information based on the capability information.

[0346] Based on the communication method shown in Figure 6, the terminal device can indicate to the network device through capability information whether the terminal device supports using the precoding matrix in the first precoding matrix set to precode the signal. This can minimize the situation where the network device instructs the terminal device to use the precoding matrix in the first precoding matrix set to precode the signal, but the terminal device is unable to determine the precoding matrix. This can reduce resource waste and improve communication reliability.

[0347] Optionally, the network device may instruct the terminal device to determine the set of precoding matrices for the first precoding matrix via third instruction information.

[0348] Specifically, network devices can send third instruction information to terminal devices; correspondingly, receiving devices can receive third instruction information from network devices.

[0349] In the first example, the third indication information is used to instruct the terminal device to precode the signal using a precoding matrix from the first precoding matrix set; or it can be described as the third indication information being used to indicate whether the terminal device is allowed to precode the signal using a precoding matrix from the first precoding matrix set.

[0350] For example, taking the third indication information occupying one bit as an example, the bit value can be set to 1 to instruct the terminal device to precode the signal using a precoding matrix from the first precoding matrix set; the bit value can be set to 0 to instruct the terminal device not to precode the signal using a precoding matrix from the first precoding matrix set. Alternatively, the bit value can be set to 0 to instruct the terminal device to precode the signal using a precoding matrix from the first precoding matrix set; the bit value can be set to 1 to instruct the terminal device not to precode the signal using a precoding matrix from the first precoding matrix set.

[0351] For example, when the network device sends a third indication message, it can instruct the terminal device to precode the signal using a precoding matrix from the first precoding matrix set; when the network device does not send a third indication message, it can instruct the terminal device not to precode the signal using a precoding matrix from the first precoding matrix set. Taking the third indication message occupying one bit as an example, when the network device sends a third indication message, the terminal device can be instructed to precode the signal using a precoding matrix from the first precoding matrix set by setting the bit value to 1; or, the terminal device can be instructed to precode the signal using a precoding matrix from the first precoding matrix set by setting the bit value to 0.

[0352] In the second example, the third indication information is used to instruct the network device to precode the signal using a precoding matrix from either the first precoding matrix set or the fourth precoding matrix set.

[0353] For example, taking the third indication information occupying one bit as an example, the bit value can be set to 1 to instruct the terminal device to precode the signal using a precoding matrix from the first precoding matrix set; the bit value can be set to 0 to instruct the terminal device to precode the signal using a precoding matrix from the fourth precoding matrix set. Alternatively, the bit value can be set to 0 to instruct the terminal device to precode the signal using a precoding matrix from the first precoding matrix set; the bit value can be set to 1 to instruct the terminal device to precode the signal using a precoding matrix from the fourth precoding matrix set.

[0354] For example, when the network device sends a third indication message, it can instruct the terminal device to precode the signal using a precoding matrix from the first precoding matrix set; when the network device does not send a third indication message, it can instruct the terminal device to precode the signal using a precoding matrix from the fourth precoding matrix set. Taking the third indication message occupying one bit as an example, when the network device sends a third indication message, the terminal device can be instructed to precode the signal using a precoding matrix from the first precoding matrix set by setting the bit value to 1; or, the terminal device can be instructed to precode the signal using a precoding matrix from the first precoding matrix set by setting the bit value to 0.

[0355] In the third example, the third indication information is used to instruct the network device to precode the signal using a precoding matrix from the first precoding matrix set or a subset of precoding matrices. Taking one bit as an example, setting the bit value to 1 instructs the terminal device to precode the signal using a precoding matrix from the first precoding matrix set; setting the bit value to 0 instructs the terminal device to precode the signal using a precoding matrix from the subset of precoding matrices. Alternatively, setting the bit value to 0 instructs the terminal device to precode the signal using a precoding matrix from the first precoding matrix set; setting the bit value to 1 instructs the terminal device to precode the signal using a precoding matrix from the subset of precoding matrices.

[0356] Based on the third example, the second and third indication information can be combined. For example, if the third indication information indicates that the signal is precoded using a precoding matrix from a subset of the precoding matrix, the second indication information can indicate the subset of the precoding matrix. Alternatively, if the third indication information indicates that the signal is precoded using a precoding matrix from a subset of the precoding matrix, and the number of precoding matrix subsets is 1, the second and third indication information can be considered as a single indication information.

[0357] Optionally, the third indication information can be located in a new field in the PUSCH configuration (such as the enhTransformPrecoderSet field).

[0358] For example, when the transformPrecoder field is configured as "enabled", the enhTransformPrecoderSet field can be added to the PUSCH configuration. That is, when the network device instructs the terminal device to transmit signals using a DFT-S-OFDM waveform, the enhTransformPrecoderSet field can be added to the PUSCH configuration.

[0359] Understandably, the terminal device can determine the set of precoding matrices to which the specific precoding matrix used for precoding is located based on the third indication information, which can improve the effectiveness of information exchange between the terminal device and the network device. In addition, since the terminal device and the network device can determine the same set of precoding matrices based on the third indication information, they can determine the same first precoding matrix, which can improve the reliability of communication.

[0360] The following describes the first precoding matrix and the first indication information, taking into account all precoding matrices in the first precoding matrix set, including the second precoding matrix set:

[0361] Among them, the partial precoding matrices in the second precoding matrix set are Z precoding matrices from the precoding matrices in the second precoding matrix set excluding the fourth precoding matrix set. Z is a positive integer.

[0362] Optionally, the Z precoding matrices can be determined based on the fourth precoding matrix.

[0363] For example, the first value corresponding to the z-th precoding matrix among the Z precoding matrices is greater than or equal to the first value corresponding to any precoding matrix in the second precoding matrix set other than the Z precoding matrices and the fourth precoding matrix set.

[0364] Where z = 1, 2, ..., Z.

[0365] The first value corresponding to the precoding matrix can be determined based on the precoding matrix and the fourth precoding matrix set. Similarly, the first value corresponding to the z-th precoding matrix can be determined based on the z-th precoding matrix and the fourth precoding matrix set.

[0366] The following example uses the z-th precoding matrix to determine the first value corresponding to the z-th precoding matrix. The method for determining the first value corresponding to the z-th precoding matrix can be applied to the first value corresponding to any precoding matrix. This application provides three possible embodiments:

[0367] In a first possible embodiment, the first value corresponding to the z-th precoding matrix is ​​the sum of the cosine values ​​of the angle between the precoding matrix and the precoding matrices in the fourth set of precoding matrices.

[0368] For example, the cosine of the angle between the z-th precoding matrix and the e-th precoding matrix can be determined based on the dot product of the z-th and e-th precoding matrices and their moduli. For instance, the cosine of the angle between the z-th and e-th precoding matrices can be the ratio of the dot product of the z-th and e-th precoding matrices to a second product, where the second product is the product of the moduli of the z-th and e-th precoding matrices. Here, e = 0, 2, ..., E-1, and E is the number of precoding matrices in the fourth precoding matrix set.

[0369] For example, taking the fourth precoding matrix set as including E precoding matrices (such as precoding matrix 0 to precoding matrix E-1), we can determine that the cosine of the angle between the z-th precoding matrix and precoding matrix 0 is cosine 0, the cosine of the angle between the z-th precoding matrix and precoding matrix 1 is cosine 1, the cosine of the angle between the z-th precoding matrix and precoding matrix 2 is cosine 2, ..., and the cosine of the angle between the z-th precoding matrix and precoding matrix E-1 is cosine E-1. Then, the first value corresponding to the z-th precoding matrix can be the sum of cosine 0, cosine 1, cosine 2, ..., cosine E-1.

[0370] For example, the first value corresponding to the z-th precoding matrix can satisfy the following formula: Among them, e=0,2,…,E-1,θ z,e This represents the angle between the z-th precoding matrix and the precoding matrix e.

[0371] In a second possible embodiment, the first value corresponding to the z-th precoding matrix is ​​the weighted average of the cosine values ​​of the angle between the precoding matrix and the precoding matrices in the fourth set of precoding matrices.

[0372] For example, taking the fourth precoding matrix set as including E precoding matrices (such as precoding matrix 0 to precoding matrix E-1), we can determine that the cosine of the angle between the z-th precoding matrix and precoding matrix 0 is cosine 0, the cosine of the angle between the z-th precoding matrix and precoding matrix 1 is cosine 1, the cosine of the angle between the z-th precoding matrix and precoding matrix 2 is cosine 2, ..., and the cosine of the angle between the z-th precoding matrix and precoding matrix E-1 is cosine E-1. Then, the first value corresponding to the z-th precoding matrix can be the ratio of the sum of cosine values ​​0, 1, 2, ..., E-1 to E.

[0373] For example, the first value corresponding to the z-th precoding matrix can satisfy the following formula:

[0374] In a third possible embodiment, the first value corresponding to the z-th precoding matrix is ​​the maximum value among the angles between the precoding matrix and the precoding matrices in the fourth set of precoding matrices.

[0375] For example, taking a fourth set of precoding matrices comprising E precoding matrices (e.g., precoding matrix 0 to precoding matrix E-1), we can determine that the cosine of the angle between the z-th precoding matrix and precoding matrix 0 is cosine 0, the cosine of the angle between the z-th precoding matrix and precoding matrix 1 is cosine 1, the cosine of the angle between the z-th precoding matrix and precoding matrix 2 is cosine 2, ..., and the cosine of the angle between the z-th precoding matrix and precoding matrix E-1 is cosine E-1. Therefore, the first value corresponding to the z-th precoding matrix can be the maximum value among cosine 0, cosine 1, cosine 2, ..., cosine E-1. For instance, assuming cosine 2 is the maximum value among cosine 0, cosine 1, cosine 2, ..., cosine E-1, we can determine that the first value corresponding to the z-th precoding matrix is ​​cosine 2.

[0376] For example, the first value corresponding to the z-th precoding matrix can satisfy the following formula: max(cos(θ) z,0 ), cos(θ) z,1 ), ..., cos(θ) z,E -1)).

[0377] Specifically, Z precoding matrices can be determined by identifying the first value corresponding to each precoding matrix in the second precoding matrix set excluding the fourth precoding matrix set.

[0378] Based on the above three possible embodiments, Z precoding matrices can be determined according to the cosine of the angle between the precoding matrices in the second precoding matrix set and the precoding matrices in the fourth precoding matrix set. This results in a larger angle between the direction corresponding to each of the Z determined precoding matrices and the direction corresponding to the precoding matrices in the fourth precoding matrix set. This makes the directions corresponding to the precoding matrices in the first precoding matrix set more dispersed, thereby improving uplink coverage performance.

[0379] Optionally, Z can be determined based on the number of precoding matrices in the fourth precoding matrix set.

[0380] In one example, Z can be the difference between the second value and the number of precoding matrices in the fourth precoding matrix set (or it can be understood as the absolute value of the difference between the second value and the number of precoding matrices in the fourth precoding matrix set).

[0381] The second value is the smallest power of 2 that is greater than or equal to the number of precoding matrices in the fourth precoding matrix set. For example, if the number of precoding matrices in the fourth precoding matrix set is 28, then a power of 2 greater than or equal to 28 can be 2. 5 ,2 6 ..., then the second value can be 2.5 .

[0382] For example, taking a fourth set of precoding matrices with 28 precoding matrices as an example, the second value can be 2. 5 If Z is 32, then Z can be 4.

[0383] For example, if the number of precoding matrices in the fourth precoding matrix set is 6, the second value can be 2. 3 If , then Z can be 2.

[0384] In another example, Z can be the number of precoding matrices in the fourth set of precoding matrices.

[0385] For example, if the number of precoding matrices in the fourth precoding matrix set is 16, then Z can be 16.

[0386] Optionally, the first set of precoding matrices may also include a fourth set of precoding matrices.

[0387] For example, when the network device instructs the device to transmit signals using a DFT-S-OFDM waveform, if N is 2, the first precoding matrix set may include two precoding matrices from the fourth precoding matrix set and the second precoding matrix set; if N is 4, the first precoding matrix set may include four precoding matrices from the fourth precoding matrix set and the second precoding matrix set; if N is 8, the first precoding matrix set may include 16 precoding matrices from the second precoding matrix set (i.e., excluding the fourth precoding matrix set).

[0388] In the case where the network device instructs the device to transmit signals using the DFT-S-OFDM waveform, if N is 8 and there is no fourth precoding matrix set corresponding to the DFT-S-OFDM waveform, 16 precoding matrices can be determined from the second precoding matrix set using the fourth precoding matrix set corresponding to the CP-OFDM waveform.

[0389] It is understandable that when the first precoding matrix set includes some precoding matrices from the fourth and second precoding matrix sets (i.e., Z precoding matrices), it is equivalent to adding Z precoding matrices to the fourth precoding matrix set. This increases the number of precoding matrices in the fourth precoding matrix set, making the corresponding directions of the precoding matrices in the fourth precoding matrix set more densely packed, thus improving uplink coverage performance. Furthermore, adding Z precoding matrices to the fourth precoding matrix set can minimize the need to adjust the number of bits occupied by the first indication information, reducing transmission overhead; it also simplifies implementation and reduces implementation complexity.

[0390] It is understood that "greater than" in this application can be replaced with "greater than or equal to", and similarly, "greater than or equal to" can be replaced with "greater than"; "less than" in this application can be replaced with "less than or equal to", and similarly, "less than or equal to" can be replaced with "less than". For example, taking the second value as the minimum of the integer powers of 2 that is greater than or equal to the number of precoding matrices in the fourth precoding matrix set, it can be replaced with the second value being the minimum of the integer powers of 2 that is greater than the number of precoding matrices in the fourth precoding matrix set. Alternatively, taking the number of precoding matrices in the precoding matrix subset as less than or equal to 2^K, it can be replaced with the number of precoding matrices in the precoding matrix subset being less than 2^K.

[0391] It is understood that the method for determining the first precoding matrix set in this application can be applied to the first precoding matrix set corresponding to DFT-S-OFDM waveforms or the first precoding matrix set corresponding to CP-OFDM waveforms, and is not limited thereto.

[0392] It is understood that the number of columns of the precoding matrix in the first precoding matrix set in this application can also be greater than 1. In this case, the method for determining the elements of each column in the precoding matrix can refer to the above description of the precoding matrix, and will not be repeated here.

[0393] Furthermore, simulations revealed that in scenarios where a first precoding matrix is ​​determined based on the first precoding matrix set in this application, enabling the terminal device to precode the signal according to the first precoding matrix and transmit the data, an uplink coverage performance gain of 0.5dB to 3dB can be obtained.

[0394] The various embodiments of this application can be implemented independently or in combination, without limitation. Unless otherwise specified or in conflict of logic, the terminology and / or descriptions between the different embodiments provided in this application are consistent and can be referenced mutually. Technical features in different embodiments can be combined to form new embodiments based on their inherent logical relationships.

[0395] It is understood that in the embodiments of this application, the executing entity may perform some or all of the steps in the embodiments of this application. These steps or operations are merely examples, and the embodiments of this application may also perform other operations or variations thereof. Furthermore, the various steps may be executed in different orders as presented in the embodiments of this application, and it is not necessarily necessary to execute all the operations in the embodiments of this application.

[0396] The foregoing primarily describes the solutions provided in this application from the perspective of device-to-device interaction. It is understood that each device, in order to achieve the aforementioned functions, includes corresponding hardware structures and / or software modules for executing each function. Those skilled in the art should readily recognize that, based on the algorithm steps of the examples described in conjunction with the embodiments disclosed herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0397] This application embodiment can divide each device into functional modules according to the above method example. For example, each function can be divided into a separate functional module, or two or more functions can be integrated into one processing module. The integrated module can be implemented in hardware or as a software functional module. The module division in this application embodiment is illustrative and only represents one logical functional division. In actual implementation, there may be other division methods.

[0398] With each function module divided according to its corresponding function, Figure 7 shows a terminal device 70. The terminal device 70 can perform the actions performed by the terminal device in the methods shown in Figures 5 and 6. All relevant content of each step involved in the above method embodiments can be referred to the functional description of the corresponding functional module. The technical effects that can be obtained can be referred to the above method embodiments, and will not be repeated here.

[0399] The terminal device 70 may include a transceiver module 701 and a processing module 702. Exemplarily, the terminal device 70 may be a communication device, or a chip or other combination device or component having the aforementioned terminal device functions applied in a communication device. When the terminal device 70 is a communication device, the transceiver module 701 may be a transceiver, which may include an antenna and radio frequency circuits, etc.; the processing module 702 may be a processor (or processing circuit), such as a baseband processor, which may include one or more CPUs. When the terminal device 70 is a component having the aforementioned terminal device functions, the transceiver module 701 may be a radio frequency unit; the processing module 702 may be a processor (or processing circuit), such as a baseband processor. When the terminal device 70 is a chip system, the transceiver module 701 may be an input / output interface of a chip (e.g., a baseband chip); the processing module 702 may be a processor (or processing circuit) of the chip system, and may include one or more central processing units. It should be understood that the transceiver module 701 in the embodiments of this application can be implemented by a transceiver or transceiver-related circuit components; the processing module 702 can be implemented by a processor or processor-related circuit components (or, referred to as processing circuit).

[0400] For example, the transceiver module 701 can be used to perform all the transceiver operations performed by the terminal device in the embodiments shown in FIG5 and FIG6, and / or to support other processes of the technology described herein; the processing module 702 can be used to perform all operations other than the transceiver operations performed by the terminal device in the embodiments shown in FIG5 and FIG6, and / or to support other processes of the technology described herein.

[0401] Figure 8 illustrates a network device 80, which can perform the actions performed by the network device in the methods shown in Figures 5 and 6 above. All relevant content of each step involved in the above method embodiments can be referred to the functional description of the corresponding functional module, and the technical effects that can be obtained can be referred to the above method embodiments, which will not be repeated here.

[0402] The network device 80 may include a transceiver module 801 and a processing module 802. Exemplarily, the network device 80 may be a communication device, or a chip or other combination of devices or components with the aforementioned network device functions applied in a communication device. When the network device 80 is a communication device, the transceiver module 801 may be a transceiver, which may include an antenna and radio frequency circuits, etc.; the processing module 802 may be a processor (or processing circuit), such as a baseband processor, which may include one or more CPUs. When the network device 80 is a component with the aforementioned network device functions, the transceiver module 801 may be a radio frequency unit; the processing module 802 may be a processor (or processing circuit), such as a baseband processor. When the network device 80 is a chip system, the transceiver module 801 may be an input / output interface of a chip (e.g., a baseband chip); the processing module 802 may be a processor (or processing circuit) of the chip system, and may include one or more central processing units. It should be understood that the transceiver module 801 in the embodiments of this application can be implemented by a transceiver or transceiver-related circuit components; the processing module 802 can be implemented by a processor or processor-related circuit components (or, referred to as processing circuit).

[0403] For example, the transceiver module 801 can be used to perform all the transceiver operations performed by the network device in the embodiments shown in FIG5 and FIG6, and / or to support other processes of the technology described herein; the processing module 802 can be used to perform all operations other than the transceiver operations performed by the network device in the embodiments shown in FIG5 and FIG6, and / or to support other processes of the technology described herein.

[0404] As another possible implementation, the transceiver module 701 in Figure 7 can be replaced by a transceiver unit that integrates the functions of the transceiver module 701; the processing module 702 can be replaced by a processor that integrates the functions of the processing module 702. Furthermore, the terminal device 70 shown in Figure 7 may also include a memory. Alternatively, the transceiver module 801 in Figure 8 can be replaced by a transceiver unit that integrates the functions of the transceiver module 801; the processing module 802 can be replaced by a processor that integrates the functions of the processing module 802. Furthermore, the network device 80 shown in Figure 8 may also include a memory.

[0405] Alternatively, when the processing module 702 is replaced by a processor and the transceiver module 701 is replaced by a transceiver, the terminal device 70 involved in the embodiments of this application can also be the communication device 90 shown in FIG. 9. Or, when the processing module 802 is replaced by a processor and the transceiver module 801 is replaced by a transceiver, the network device 80 involved in the embodiments of this application can also be the communication device 90 shown in FIG. 9.

[0406] The processor can be logic circuit 901, and the transceiver can be interface circuit 902. Furthermore, the communication device 90 shown in Figure 9 may also include a memory 903.

[0407] This application also provides a computer program product that, when executed by a computer, can implement the functions of any of the above method embodiments.

[0408] This application also provides a computer program that, when executed by a computer, can implement the functions of any of the above method embodiments.

[0409] This application also provides a computer-readable storage medium. All or part of the processes in the above method embodiments can be implemented by a computer program instructing related hardware. This program can be stored in the computer-readable storage medium, and when executed, it can include the processes of the above method embodiments. The computer-readable storage medium can be an internal storage unit of the terminal (including a data sending end and / or a data receiving end) of any of the foregoing embodiments, such as the terminal's hard disk or memory. The computer-readable storage medium can also be an external storage device of the terminal, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc., equipped on the terminal. Further, the computer-readable storage medium can include both the terminal's internal storage unit and external storage devices. The computer-readable storage medium is used to store the computer program and other programs and data required by the terminal. The computer-readable storage medium can also be used to temporarily store data that has been output or will be output.

[0410] The terms "first" and "second," etc., used in the specification, claims, and drawings of this application are used to distinguish different objects, not to describe a specific order. "First" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" and "second" may explicitly or implicitly include one or more of that feature. In the description of this embodiment, unless otherwise stated, "a plurality of" means two or more.

[0411] Furthermore, the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus.

[0412] It should be understood that in this application, "at least one (item)" means one or more. "More than one" means two or more. "At least two (items)" means two or three or more. "And / or" is used to describe the relationship between related objects, indicating that there can be three relationships. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the related objects before and after are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple. Both "...when" and "if" indicate that a corresponding action will be taken under certain objective circumstances. They are not time limits, nor do they require a judgment action to be taken when the action is taken, nor do they imply any other limitations.

[0413] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a specific manner to facilitate understanding.

[0414] In this application, "sending information to...(terminal device)" can be understood as the destination of the information being the terminal device. This can include sending information directly or indirectly to the terminal device. "Receiving information from...(terminal device)" can be understood as the source of the information being the terminal device, and can include receiving information directly or indirectly from the terminal device. Information may undergo necessary processing between the source and destination, such as format changes, but the destination can understand the valid information from the source.

[0415] Through the above description of the embodiments, those skilled in the art can clearly understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0416] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0417] The units described as separate components may or may not be physically separate. A component shown as a unit can be one or more physical units; that is, it can be located in one place or distributed in multiple different locations. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0418] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0419] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solution of this application embodiment, or all or part of the technical solution, can be embodied in the form of a software product. This software product is stored in a storage medium and includes several instructions to cause a device (which may be a microcontroller, chip, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, ROM, RAM, magnetic disks, or optical disks.

Claims

1. A communication method, characterized in that, include: The system receives first indication information; wherein the first indication information is used to indicate a first precoding matrix; the first precoding matrix is ​​contained in a first precoding matrix set, the precoding matrix in the first precoding matrix set is an N-row, 1-column matrix, where N is the number of antenna ports of the terminal device; the first precoding matrix set includes some or all of the precoding matrices in a second precoding matrix set, the second precoding matrix set includes X precoding matrices, where X is determined according to N and the number of phases corresponding to the modulation method, and X is greater than 4; the elements in the first row of the precoding matrix in the second precoding matrix set are 1, and the elements in the second to Nth rows are determined according to the phases corresponding to the modulation method; both N and X are positive integers. The signal is precoded according to the first precoding matrix.

2. The method according to claim 1, characterized in that, X is the (N-1)th power of the number of phases corresponding to the modulation method.

3. The method according to claim 1 or 2, characterized in that, The elements of the k-th row of the precoding matrix in the second precoding matrix set are determined according to one of the phases corresponding to the modulation scheme, k = 2, 3, ..., N.

4. The method according to claim 1, characterized in that, When N is greater than 2 The precoding matrix in the second set of precoding matrices includes a first matrix and a second matrix. The absolute value of the difference between the phase corresponding to the element in each row of the first matrix and the phase corresponding to the element in a row of the second matrix is ​​the first phase difference. The first matrix and the second matrix are both A-row, 1-column matrices, where A is a positive integer less than or equal to N / 2.

5. The method according to claim 4, characterized in that, The first phase difference is contained in a first set; wherein the first set is determined according to the phase corresponding to the modulation method, or the first set is predefined.

6. The method according to claim 5, characterized in that, The first set includes the absolute value of the difference between any two phases corresponding to the modulation scheme.

7. The method according to any one of claims 1-6, characterized in that, The first indication information is used to indicate the index of the first precoding matrix in the first precoding matrix set; or Receive second indication information, the second indication information being used to indicate a subset of the precoding matrix, and the first indication information being used to indicate the index of the first precoding matrix in the subset of the precoding matrix.

8. The method according to claim 7, characterized in that, The beam angles corresponding to the precoding matrices in the subset of the precoding matrices are located within a preset range.

9. The method according to claim 7 or 8, characterized in that, The number of precoding matrices in the precoding matrix subset is less than or equal to 2 to the power of K, where K is the number of bits occupied by the first indication information.

10. The method according to claim 7, characterized in that, The precoding matrix subset includes a third matrix and a fourth matrix. The absolute value of the difference between the phase corresponding to an element in a row of the third matrix and the phase corresponding to an element in a row of the fourth matrix is ​​the second phase difference. The third matrix and the fourth matrix are both B-row, 1-column matrices, where B is a positive integer and B is less than or equal to N / 2.

11. The method according to claim 10, characterized in that, The second phase difference is determined according to the phase corresponding to the modulation method; or The second phase difference is predefined.

12. The method according to claim 10 or 11, characterized in that, The second phase difference is the absolute value of the difference between any two phases corresponding to the modulation method.

13. The method according to claim 7, characterized in that, The subset of precoding matrices includes C precoding matrices in the second set of precoding matrices. The angle between each of the C precoding matrices and the fifth matrix is ​​the sum of a first angle and one of one or more angle intervals. The fifth matrix is ​​any precoding matrix in the second set of precoding matrices. The first angle is the minimum angle between each precoding matrix in the second set of precoding matrices other than the fifth matrix and the fifth matrix.

14. The method according to any one of claims 1-13, characterized in that, The method further includes: Receive third indication information from the network device; wherein the third indication information is used to instruct the terminal device to precode the signal using a precoding matrix from the first precoding matrix set.

15. The method according to any one of claims 1-14, characterized in that, The method further includes: Send the terminal device's capability information to the network device; wherein the capability information is used to indicate whether the terminal device supports precoding the signal using the precoding matrices in the first precoding matrix set.

16. The method according to any one of claims 1-15, characterized in that, The first set of precoding matrices further includes a third set of precoding matrices; wherein the third set of precoding matrices includes partially phase interfering coding matrices; wherein one or more elements in the partially phase interfering coding matrices are 0.

17. The method according to any one of claims 1-6, characterized in that, When the first precoding matrix set includes a portion of the precoding matrices from the second precoding matrix set, the portion of the precoding matrices consists of Z precoding matrices from the second precoding matrix set excluding the fourth precoding matrix set. The first value corresponding to the z-th precoding matrix among the Z precoding matrices is greater than or equal to the first value corresponding to any precoding matrix in the second precoding matrix set other than the Z precoding matrices and the fourth precoding matrix set; Wherein, the first value corresponding to the precoding matrix is ​​determined according to the precoding matrix and the fourth precoding matrix set; z = 1, 2, ..., Z, where Z is a positive integer, and the number of precoding matrices in the fourth precoding matrix set is less than the number of precoding matrices in the second precoding matrix set.

18. The method according to claim 17, characterized in that, The first value corresponding to the precoding matrix is ​​the sum of the cosines of the angle between the precoding matrix and the precoding matrices in the fourth precoding matrix set; or The first value corresponding to the precoding matrix is ​​the weighted average of the cosine values ​​of the angle between the precoding matrix and the precoding matrices in the fourth precoding matrix set; or The first value corresponding to the precoding matrix is ​​the maximum value among the angles between the precoding matrix and the precoding matrices in the fourth set of precoding matrices.

19. The method according to claim 17 or 18, characterized in that, The first set of precoding matrices also includes the fourth set of precoding matrices.

20. A communication method, characterized in that, include: Obtain first indication information; wherein, the first indication information is used to indicate a first precoding matrix; the first precoding matrix is ​​contained in a first precoding matrix set, the precoding matrix in the first precoding matrix set is an N-row, 1-column matrix, where N is the number of antenna ports of the terminal device; the first precoding matrix set includes some or all of the precoding matrices in a second precoding matrix set, the second precoding matrix set includes X precoding matrices, where X is determined according to N and the number of phases corresponding to the modulation method, and X is greater than 4; the elements in the first row of the precoding matrix in the second precoding matrix set are 1, and the elements in the second to Nth rows are determined according to the phases corresponding to the modulation method; N and X are both positive integers; Send the first instruction information.

21. The method according to claim 20, characterized in that, X is the (N-1)th power of the number of phases corresponding to the modulation method.

22. The method according to claim 20 or 21, characterized in that, The elements of the k-th row of the precoding matrix in the second precoding matrix set are determined according to one of the phases corresponding to the modulation scheme, k = 2, 3, ..., N.

23. The method according to claim 20, characterized in that, When N is greater than 2 The precoding matrix in the second set of precoding matrices includes a first matrix and a second matrix. The absolute value of the difference between the phase corresponding to the element in each row of the first matrix and the phase corresponding to the element in a row of the second matrix is ​​the first phase difference. The first matrix and the second matrix are both A-row, 1-column matrices, where A is a positive integer less than or equal to N / 2.

24. The method according to claim 23, characterized in that, The first phase difference is contained in a first set; wherein the first set is determined according to the phase corresponding to the modulation method, or the first set is predefined.

25. The method according to claim 24, characterized in that, The first set includes the absolute value of the difference between any two phases corresponding to the modulation scheme.

26. The method according to any one of claims 20-25, characterized in that, The first indication information includes the index information of the first precoding matrix; or Send a second instruction message, the second instruction message including index information of a subset of the precoded matrix, and the first instruction message including index information of the first precoded matrix in the subset of the precoded matrix.

27. The method according to claim 26, characterized in that, The beam angles corresponding to the precoding matrices in the subset of the precoding matrices are located within a preset range.

28. The method according to claim 26 or 27, characterized in that, The number of precoding matrices in the precoding matrix subset is less than or equal to 2 to the power of K, where K is the number of bits occupied by the first indication information.

29. The method according to claim 26, characterized in that, The precoding matrix subset includes a third matrix and a fourth matrix. The absolute value of the difference between the phase corresponding to an element in a row of the third matrix and the phase corresponding to an element in a row of the fourth matrix is ​​the second phase difference. The third matrix and the fourth matrix are both B-row, 1-column matrices, where B is a positive integer and B is less than or equal to N / 2.

30. The method according to claim 29, characterized in that, The second phase difference is determined according to the phase corresponding to the modulation method; or The second phase difference is predefined.

31. The method according to claim 29 or 30, characterized in that, The second phase difference is the absolute value of the difference between any two phases corresponding to the modulation method.

32. The method according to claim 26, characterized in that, The subset of precoding matrices includes C precoding matrices in the second set of precoding matrices. The angle between each of the C precoding matrices and the fifth matrix is ​​the sum of a first angle and one of one or more angle intervals. The fifth matrix is ​​any precoding matrix in the second set of precoding matrices. The first angle is the minimum angle between each precoding matrix in the second set of precoding matrices other than the fifth matrix and the fifth matrix.

33. The method according to any one of claims 20-32, characterized in that, The method further includes: Send a third instruction message; wherein the third instruction message instructs the terminal device to precode the signal using a precoding matrix from the first precoding matrix set.

34. The method according to any one of claims 20-33, characterized in that, The method further includes: Receive capability information from the terminal device; wherein the capability information is used to indicate whether the terminal device supports precoding the signal using precoding matrices in the first set of precoding matrices.

35. The method according to any one of claims 20-34, characterized in that, The first set of precoding matrices further includes a third set of precoding matrices; wherein the third set of precoding matrices includes partially phase interfering coding matrices; wherein one or more elements in the partially phase interfering coding matrices are 0.

36. The method according to any one of claims 20-35, characterized in that, When the first precoding matrix set includes a portion of the precoding matrices from the second precoding matrix set, the portion of the precoding matrices consists of Z precoding matrices from the second precoding matrix set excluding the fourth precoding matrix set. The first value corresponding to the z-th precoding matrix among the Z precoding matrices is greater than or equal to the first value corresponding to any precoding matrix in the second precoding matrix set other than the Z precoding matrices and the fourth precoding matrix set; Wherein, the first value corresponding to the precoding matrix is ​​determined according to the precoding matrix and the fourth precoding matrix set; z = 1, 2, ..., Z, where Z is a positive integer, and the number of precoding matrices in the fourth precoding matrix set is less than the number of precoding matrices in the second precoding matrix set.

37. The method according to claim 36, characterized in that, The first value corresponding to the precoding matrix is ​​the sum of the cosines of the angle between the precoding matrix and the precoding matrices in the fourth precoding matrix set; or The first value corresponding to the precoding matrix is ​​the weighted average of the cosine values ​​of the angle between the precoding matrix and the precoding matrices in the fourth precoding matrix set; or The first value corresponding to the precoding matrix is ​​the maximum value among the angles between the precoding matrix and the precoding matrices in the fourth set of precoding matrices.

38. The method according to claim 36 or 37, characterized in that, The first set of precoding matrices also includes the fourth set of precoding matrices.

39. A communication device, characterized in that, The communication device includes a processor; the processor is configured to run a computer program or instructions that cause the communication method as described in any one of claims 1-19 to be executed, or cause the communication method as described in any one of claims 20-38 to be executed.

40. A communication device, characterized in that, The communication device includes an interface circuit and a logic circuit; the interface circuit is used to input and / or output information; the logic circuit is used to execute the communication method as described in any one of claims 1-19, or to execute the communication method as described in any one of claims 20-38, and to process and / or generate the information based on the information.

41. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions or programs that, when executed on a computer, cause the communication method as described in any one of claims 1-19 to be executed, or cause the communication method as described in any one of claims 20-38 to be executed.

42. A computer program product, characterized in that, The computer program product includes computer instructions; when some or all of the computer instructions are executed on a computer, they cause the communication method as described in any one of claims 1-19 to be executed, or cause the communication method as described in any one of claims 20-38 to be executed.

43. A chip, characterized in that, The chip includes: a processor coupled to a memory for storing programs or instructions, which, when executed by the processor, cause the communication method as described in any one of claims 1-19 to be executed, or cause the communication method as described in any one of claims 20-38 to be executed.

44. A communication system, characterized in that, The communication system includes a communication device for performing the communication method as described in any one of claims 1-19, and a communication device for performing the communication method as described in any one of claims 20-38.

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