Channel information feedback method and communication device

Abstract

The present application provides a channel information feedback method and a communication device. In the method, the first information and the SCI have the same priority in the UCI transmitted by the terminal device. The first indication information indicates a second frequency domain DFT vector set selected by the terminal device, and the SCI indicates a space-frequency vector corresponding to the strongest coefficient of the first space-frequency vector set corresponding to the second frequency domain DFT vector set and the CSI-RS port selected by the terminal device. In other words, the SCI indicates a space-frequency vector corresponding to the second frequency domain DFT vector set selected by the terminal device and corresponding to the strongest coefficient, so that the network device obtains a weighting coefficient of the strongest space-frequency vector corresponding to the downlink channel based on the SCI and the first information that have the same priority and are included in the UCI. Thus, the UCI reporting resource is limited, and the terminal device feeds back at least the SCI and the first information, corresponding to the SCI, and the accuracy of the frequency domain position determined by the network device based on the SCI and the first information is improved, ensuring the effectiveness of the precoding matrix as much as possible.

Description

[Technical Field]

[0001] The present application relates to the field of wireless technology, and in particular to a channel information feedback method and communication device. [Background technology]

[0002] Multiple-input multiple-output (MIMO) technology is a core technology of the long-term evolution (LTE) system and the 5th generation (5G) new radio (NR). A network device may obtain the downlink optimal precoding matrix using precoding matrix indicator (PMI)-related information transmitted by a terminal device. The PMI-related information is carried in uplink control information (UCI).

[0003] Currently, a terminal device must perform selection based on a space-frequency vector set jointly corresponding to a frequency-domain discrete Fourier transform (DFT) vector set configured by a network device and a channel state information reference signal (CSI-RS) port, and use indication information corresponding to the selection result as part or all of the PMI-related information. For example, the indication information corresponding to the selection result includes at least frequency-domain indication information indicating the selected frequency-domain DFT vector and a strongest coefficient indicator (SCI). The SCI indicates the space-frequency vector corresponding to the strongest coefficient among multiple weighting coefficients corresponding to the selected space-frequency vector set.

[0004] In the prior art, a terminal device selects several frequency-domain DFT vectors from a universal set of frequency-domain DFT vector sets. The terminal device may perform a cyclic shift on the universal set of frequency-domain DFT vector sets to shift the frequency-domain DFT vector corresponding to the SCI to a position with an index of 0 in the frequency-domain DFT vector set corresponding to the universal set. In other words, the network device may determine that the index of the frequency-domain DFT vector of the SCI is 0 by default. As a result, the SCI is not correlated with the frequency-domain indication information indicating the selected frequency-domain DFT vector. When uplink resources are limited due to poor channel quality or a large number of terminal devices communicating with the network device, the terminal device may report only high-priority information (e.g., SCI) among the UCIs and discard some low-priority information (e.g., frequency-domain indication information) among the UCIs.

[0005] However, if a terminal device selects some frequency-domain DFT vectors from a subset of the frequency-domain DFT vector set, and if the terminal device performs cyclic shifting on the subset of the frequency-domain DFT vector set, the position of the frequency-domain DFT vector corresponding to the SCI in the frequency-domain DFT vector set corresponding to the universal set of the frequency-domain DFT vector set may not be a position with an index of 0. When the prior art UCI reporting method is still used and UCI reporting resources are limited, the network device may obtain only the SCI from the UCI but not the frequency-domain indication information. As a result, the frequency-domain position corresponding to the SCI and determined by the network device may be inaccurate. This affects the accuracy of precoding performed by the network device and further affects communication efficiency. Summary of the Invention

[0006] The embodiments of the present application provide a channel information feedback method and a communication device, so that a network device obtains a weighting coefficient of the strongest space-frequency vector corresponding to a downlink channel based on the SCI and first information, which have the same priority and are included in the UCI. Therefore, when UCI reporting resources are limited, the terminal device feeds back at least the SCI and the first information indicating a second frequency-domain DFT vector set, so that the accuracy of the frequency-domain position corresponding to the SCI and determined by the network device based on the SCI and the first information is improved to ensure the effectiveness of the precoding matrix as much as possible.

[0007] A first aspect of an embodiment of the present application provides a channel information feedback method. The method may be implemented by a terminal device or a component (e.g., a processor, a chip, or a chip system) of the terminal device. In this method, the terminal device first receives first indication information, where the first indication information indicates a first frequency-domain DFT vector set, a subset of the first frequency-domain DFT vector set includes a second frequency-domain DFT vector set, and the second frequency-domain DFT vector set and a CSI-RS port selected by the terminal device correspond to a first space-frequency vector set; then, the terminal device determines a strongest coefficient indicator (SCI) based on the first indication information, where the SCI indicates a space-frequency vector corresponding to a strongest coefficient of the first space-frequency vector set; then, the terminal device transmits uplink control information (UCI), where the UCI includes the first information and the SCI, where the first information indicates the second frequency-domain DFT vector set, and the first information and the SCI have the same priority in the UCI.

[0008] Optionally, the first information and the SCI have the same priority in the UCI, in other words the priority of the first information in the UCI is the same as the priority of the SCI in the UCI.

[0009] Based on the above technical solution, in the UCI transmitted by the terminal device, the priority of the first information is the same as the priority of the SCI. The first information indicates a second frequency-domain DFT vector set selected by the terminal device, and the SCI indicates a space-frequency vector corresponding to the strongest coefficient of the space-frequency vector set corresponding to the second frequency-domain DFT vector set and the CSI-RS port selected by the terminal device. In other words, the SCI indicates the space-frequency vector corresponding to the second frequency-domain DFT vector set selected by the terminal device and corresponding to the strongest coefficient. Thus, the network device obtains a weighting coefficient of the strongest space-frequency vector corresponding to the downlink channel based on the SCI and the first information, which have the same priority and are included in the UCI. Therefore, when UCI reporting resources are limited, the terminal device feeds back at least the SCI and the first information indicating the second frequency-domain DFT vector set, so that the accuracy of the frequency-domain position corresponding to the SCI and determined by the network device based on the SCI and the first information is improved to ensure the effectiveness of the precoding matrix as much as possible.

[0010] A second aspect of an embodiment of the present application provides a channel information feedback method. The method may be implemented by a network device or a component (e.g., a processor, a chip, or a chip system) of the network device. In this method, the network device first transmits first indication information, where the first indication information indicates a first frequency-domain DFT vector set, a subset of the first frequency-domain DFT vector set includes a second frequency-domain DFT vector set, and the second frequency-domain DFT vector set and a CSI-RS port selected by the terminal device correspond to a first space-frequency vector set; then, the network device receives uplink control information UCI, where the UCI includes first information and SCI, where the SCI indicates a space-frequency vector corresponding to a strongest coefficient of the first space-frequency vector set, the first information indicates the second frequency-domain DFT vector set, and the first information and the SCI have the same priority in the UCI.

[0011] Optionally, the first information and the SCI have the same priority in the UCI, in other words the priority of the first information in the UCI is the same as the priority of the SCI in the UCI.

[0012] Based on the above technical solution, in the UCI received by the network device, the priority of the first information is the same as the priority of the SCI. The first information indicates a second frequency-domain DFT vector set selected by the terminal device, and the SCI indicates a space-frequency vector corresponding to the strongest coefficient of the space-frequency vector set corresponding to the second frequency-domain DFT vector set and the CSI-RS port selected by the terminal device. In other words, the SCI indicates the space-frequency vector corresponding to the second frequency-domain DFT vector set selected by the terminal device and corresponding to the strongest coefficient. Thus, the network device obtains a weighting coefficient of the strongest space-frequency vector corresponding to the downlink channel based on the SCI and the first information, which have the same priority and are included in the UCI. Therefore, when UCI reporting resources are limited, the terminal device feeds back at least the SCI and the first information indicating the second frequency-domain DFT vector set, so that the accuracy of the frequency-domain position corresponding to the SCI and determined by the network device based on the SCI and the first information is improved to ensure the effectiveness of the precoding matrix as much as possible.

[0013] In a possible implementation of the first or second aspect of the embodiment of the present application, the number of bits occupied by the SCI is correlated with the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors.

[0014] Based on the above technical solution, the SCI indicates a spatial-frequency vector corresponding to the second frequency-domain DFT vector set selected by the terminal device and corresponding to the strongest coefficient. The SCI may use at least some occupied bits to indicate the position of the strongest coefficient of the second frequency-domain DFT vector set and the frequency-domain DFT vector selected by the terminal device.

[0015] In a possible implementation of the first or second aspect of the embodiment of the present application, the number of bits occupied by the SCI is further correlated with the number of CSI-RS ports.

[0016] Based on the above technical solution, the SCI indicates a space-frequency vector corresponding to the strongest coefficient of the space-frequency vector set corresponding to the second frequency-domain DFT vector set selected by the terminal device and the CSI-RS port selected by the terminal device, and the SCI may indicate the position of the strongest coefficient and of the CSI-RS port selected by the terminal device in the selected CSI-RS port using at least some reserved bits.

[0017] In a possible implementation of the first or second aspect of the embodiment of the present application, the quantity of bits occupied by the SCI satisfies a first scheme, and this first scheme is:

[0018]

number

[0019] where 2L represents the number of CSI-RS ports and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors.

[0020] Note that in this and later embodiments, 2L denotes the quantity of CSI-RS ports selected (if dual polarization directions are used, L CSI-RS ports are selected for each polarization direction), and M denotes the quantity of frequency-domain DFT vectors selected.

[0021] In a possible implementation of the first or second aspect of the embodiment of the present application, the quantity of bits occupied by the SCI satisfies a second scheme, and this second scheme is:

[0022]

number

[0023] where 2L represents the number of CSI-RS ports and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors.

[0024] In a possible implementation of the first or second aspect of the embodiment of the present application, the quantity of bits occupied by the first information satisfies a third scheme, and the third scheme is as follows:

[0025]

number

[0026] where N represents the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors, and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors;

[0027]

number

[0028] represents the number of combinations of N to M items.

[0029] Based on the above technical solution, the first information indicates a second set of frequency-domain DFT vectors selected by the terminal device. When a circular shift is not performed on the frequency-domain DFT vectors, the first information of the terminal device includes a position indicator of the frequency-domain DFT vector corresponding to the strongest coefficient, so that the number of bits occupied by the first information is correlated with the number N of frequency-domain DFT vectors configured by the network device and the number M of frequency-domain DFT vectors selected by the terminal device, and N and M are represented in a third manner using the number of bits. Therefore, the terminal device does not need to perform a circular shift on the frequency-domain DFT vectors, thereby reducing implementation complexity.

[0030] In a possible implementation of the first or second aspect of the embodiment of the present application, the quantity of bits occupied by the first information satisfies a fourth scheme, and this fourth scheme is:

[0031]

number

[0032] where N represents the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors, and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors;

[0033]

number

[0034] represents the number of combinations between N-1 and M-1 items.

[0035] Based on the above technical solution, the first information indicates a second set of frequency-domain DFT vectors selected by the terminal device. When the terminal device performs a circular shift on the first set of frequency-domain DFT vectors so that the index of the frequency-domain DFT vector corresponding to the strongest coefficient indicated by the SCI becomes 0, the terminal device assumes by default that the frequency-domain DFT vector corresponding to the strongest coefficient is definitely selected. Therefore, the number of bits occupied by the first information is correlated with the number N-1 of frequency-domain DFT vectors configured by the network device and from which the frequency-domain DFT vector corresponding to the strongest coefficient is removed, and the number M-1 of frequency-domain DFT vectors selected by the terminal device and from which the frequency-domain DFT vector corresponding to the strongest coefficient is removed, where N-1 and M-1 are indicated using the number of bits in the fourth scheme. Therefore, the bit overhead of the SCI is reduced.

[0036] In a third aspect of an embodiment of the present application, there is provided a communication device including a transceiver unit and a processing unit.

[0037] The transceiver unit is configured to receive first indication information, the first indication information indicating a first frequency domain DFT vector set, a subset of the first frequency domain DFT vector set including a second frequency domain DFT vector set; communication equipment The CSI-RS port selected by corresponds to the first space-frequency vector set.

[0038] The processing unit is configured to determine a strongest coefficient indicator SCI based on the first indication information, the SCI indicating a spatial frequency vector corresponding to a strongest coefficient of the set of spatial frequency vectors.

[0039] The transceiver unit is further configured to transmit uplink control information UCI, the UCI including first information and SCI, the first information indicating a second frequency domain DFT vector set, and the first information and the SCI having the same priority in the UCI.

[0040] Optionally, the first information and the SCI have the same priority in the UCI, in other words the priority of the first information in the UCI is the same as the priority of the SCI in the UCI.

[0041] Based on the above technical solution, in the UCI transmitted by the transceiver unit, the priority of the first information is the same as the priority of the SCI. The first information indicates a second frequency-domain DFT vector set selected by the terminal device, and the SCI indicates a space-frequency vector corresponding to the strongest coefficient of the space-frequency vector set corresponding to the second frequency-domain DFT vector set and the CSI-RS port selected by the terminal device. In other words, the SCI indicates the space-frequency vector corresponding to the second frequency-domain DFT vector set selected by the terminal device and corresponding to the strongest coefficient. Thus, the network device obtains a weighting coefficient of the strongest space-frequency vector corresponding to the downlink channel based on the SCI and the first information, which have the same priority and are included in the UCI. Therefore, when UCI reporting resources are limited, the terminal device feeds back at least the SCI and the first information indicating the second frequency-domain DFT vector set, so that the accuracy of the frequency-domain position corresponding to the SCI and determined by the network device based on the SCI and the first information is improved to ensure the effectiveness of the precoding matrix as much as possible.

[0042] In a fourth aspect of an embodiment of the present application, there is provided a communication device including a transmitting unit and a receiving unit.

[0043] The transmitting unit is configured to transmit first indication information, the first indication information indicating a first frequency-domain DFT vector set, a subset of the first frequency-domain DFT vector set including a second frequency-domain DFT vector set, and the second frequency-domain DFT vector set and a CSI-RS port selected by the terminal device correspond to the first spatial-frequency vector set.

[0044] The receiving unit is configured to receive uplink control information UCI, the UCI including first information and SCI, the SCI indicating a space-frequency vector corresponding to a strongest coefficient of the space-frequency vector set, the first information indicating a second frequency-domain DFT vector set, and the first information and the SCI having the same priority in the UCI.

[0045] Optionally, the first information and the SCI have the same priority in the UCI, in other words the priority of the first information in the UCI is the same as the priority of the SCI in the UCI.

[0046] Based on the above technical solution, in the UCI received by the receiving unit, the priority of the first information is the same as the priority of the SCI. The first information indicates a second frequency-domain DFT vector set selected by the terminal device, and the SCI indicates a space-frequency vector corresponding to the strongest coefficient of the space-frequency vector set corresponding to the second frequency-domain DFT vector set and the CSI-RS port selected by the terminal device. In other words, the SCI indicates the space-frequency vector corresponding to the second frequency-domain DFT vector set selected by the terminal device and corresponding to the strongest coefficient. Thus, the network device obtains a weighting coefficient of the strongest space-frequency vector corresponding to the downlink channel based on the SCI and the first information, which have the same priority and are included in the UCI. Therefore, when UCI reporting resources are limited, the terminal device feeds back at least the SCI and the first information indicating the second frequency-domain DFT vector set, so that the accuracy of the frequency-domain position corresponding to the SCI and determined by the network device based on the SCI and the first information is improved to ensure the effectiveness of the precoding matrix as much as possible.

[0047] In a possible implementation of the third or fourth aspect of the embodiment of the present application, the number of bits occupied by the SCI is correlated with the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors.

[0048] In a possible implementation of the third or fourth aspect of the embodiment of the present application, the quantity of bits occupied by the SCI is further correlated with the quantity of CSI-RS ports.

[0049] In a possible implementation of the third or fourth aspect of the embodiment of the present application, the quantity of bits occupied by the SCI satisfies a first scheme, and this first scheme is:

[0050]

number

[0051] where 2L represents the number of CSI-RS ports and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors.

[0052] In a possible implementation of the third or fourth aspect of the embodiment of the present application, the quantity of bits occupied by the SCI satisfies a second scheme, and this second scheme is:

[0053]

number

[0054] where 2L represents the number of CSI-RS ports and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors.

[0055] In a possible implementation of the third or fourth aspect of the embodiment of the present application, the quantity of bits occupied by the first information satisfies a third scheme, and this third scheme is:

[0056]

number

[0057] where N represents the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors, and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors;

[0058]

number

[0059] represents the number of combinations of N to M items.

[0060] In a possible implementation of the third or fourth aspect of the embodiment of the present application, the quantity of bits occupied by the first information satisfies a fourth scheme, and this fourth scheme is:

[0061]

number

[0062] where N represents the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors, and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors;

[0063]

number

[0064] represents the number of combinations between N-1 and M-1 items.

[0065] For a description of multiple possible implementations of the third and fourth aspects and corresponding technical effects, please refer to the above description of multiple possible implementations of the first and second aspects and corresponding technical effects, and the details will not be described again in this specification.

[0066] A fifth aspect of an embodiment of the present application provides a channel information feedback method. The method may be implemented by a terminal device or a component (e.g., a processor, a chip, or a chip system) of the terminal device. In this method, the terminal device first receives first indication information, where the first indication information indicates a first frequency-domain DFT vector set, a subset of the first frequency-domain DFT vector set includes a second frequency-domain DFT vector set, and the first frequency-domain DFT vector set and a CSI-RS port selected by the terminal device correspond to a second space-frequency vector set; then, the terminal device determines a strongest coefficient indicator (SCI) based on the first indication information, where the SCI indicates a space-frequency vector corresponding to a strongest coefficient of the second space-frequency vector set; then, the terminal device transmits uplink control information (UCI), where the UCI includes the first information and the SCI, and the first information indicates the second frequency-domain DFT vector set, and the priority of the first information in the UCI is lower than the priority of the SCI in the UCI.

[0067] Optionally, the priority of the first information in the UCI is lower than the priority of the SCI in the UCI, in other words, the priority of the SCI in the UCI is higher than the priority of the first information in the UCI.

[0068] Based on the above technical solution, in the UCI transmitted by the terminal device, the first information has a lower priority than the SCI. The first information indicates a second frequency-domain DFT vector set selected by the terminal device, and the SCI indicates a space-frequency vector corresponding to the strongest coefficient of the space-frequency vector set corresponding to the first frequency-domain DFT vector set configured by the network device and the CSI-RS port selected by the terminal device. In other words, the SCI indicates the space-frequency vector corresponding to the first frequency-domain DFT vector set configured by the network device and corresponding to the strongest coefficient, and there is no correlation between the SCI and the second frequency-domain DFT vector set selected by the terminal device so that the network device can obtain the weighting coefficient of the strongest space-frequency vector corresponding to the downlink channel based on the high-priority SCI included in the UCI. Therefore, when UCI reporting resources are limited, the terminal device feeds back at least the SCI so that the accuracy of the frequency-domain position corresponding to the SCI and determined by the network device based on the SCI can be improved, thereby ensuring the effectiveness of the precoding matrix as much as possible. In addition, when UCI reporting resources are limited, the terminal device may not need to feed back the first information, so that overhead can be reduced to a certain extent.

[0069] A sixth aspect of the present application provides a channel information feedback method. The method may be implemented by a network device or a component (e.g., a processor, a chip, or a chip system) of the network device. In this method, the network device first transmits first indication information, where the first indication information indicates a first frequency-domain DFT vector set, a subset of the first frequency-domain DFT vector set includes a second frequency-domain DFT vector set, and the first frequency-domain DFT vector set and a CSI-RS port selected by the terminal device correspond to a second space-frequency vector set; then, the network device receives uplink control information UCI, where the UCI includes first information and SCI, where the SCI indicates a space-frequency vector corresponding to a strongest coefficient of the second space-frequency vector set, and the first information indicates the second frequency-domain DFT vector set, and the priority of the first information in the UCI is lower than the priority of the SCI in the UCI.

[0070] Optionally, the priority of the first information in the UCI is lower than the priority of the SCI in the UCI, in other words, the priority of the SCI in the UCI is higher than the priority of the first information in the UCI.

[0071] Based on the above technical solution, in the UCI received by the network device, the first information has a lower priority than the SCI. The first information indicates a second frequency-domain DFT vector set selected by the terminal device, and the SCI indicates a space-frequency vector corresponding to the strongest coefficient of the space-frequency vector set corresponding to the first frequency-domain DFT vector set configured by the network device and the CSI-RS port selected by the terminal device. In other words, the SCI indicates the space-frequency vector corresponding to the first frequency-domain DFT vector set configured by the network device and corresponding to the strongest coefficient, and there is no correlation between the SCI and the second frequency-domain DFT vector set selected by the terminal device so that the network device can obtain the weighting coefficient of the strongest space-frequency vector corresponding to the downlink channel based on the high-priority SCI included in the UCI. Therefore, when UCI reporting resources are limited, the terminal device feeds back at least the SCI so that the accuracy of the frequency-domain position corresponding to the SCI and determined by the network device based on the SCI can be improved, thereby ensuring the effectiveness of the precoding matrix as much as possible. In addition, when UCI reporting resources are limited, the terminal device may not need to feed back the first information, so that overhead can be reduced to a certain extent.

[0072] In a possible implementation of the fifth or sixth aspect of the embodiment of the present application, the number of bits occupied by the SCI is correlated with the number of frequency domain DFT vectors in the first frequency domain DFT vector set.

[0073] Based on the above technical solution, the SCI indicates a space-frequency vector corresponding to a first frequency-domain DFT vector set configured by the network device and corresponding to the strongest coefficient, and the SCI may use at least some occupied bits to indicate the position of the strongest coefficient of the first frequency-domain DFT vector set and the frequency-domain DFT vector selected by the terminal device.

[0074] In a possible implementation of the fifth or sixth aspect of the embodiment of the present application, the number of bits occupied by the SCI is further correlated with the number of CSI-RS ports.

[0075] Based on the aforementioned technical solutions, SCI: network By device composition The SCI may indicate the space-frequency vector corresponding to the strongest coefficient of the space-frequency vector set corresponding to the first frequency-domain DFT vector set obtained from the first frequency-domain DFT vector set and the CSI-RS port selected by the terminal device. The SCI may indicate the location of the strongest coefficient and of the CSI-RS port selected by the terminal device in the selected CSI-RS port using at least some of the reserved bits.

[0076] In a possible implementation of the fifth or sixth aspect of the embodiment of the present application, the quantity of bits occupied by the SCI satisfies a fifth scheme, which is:

[0077]

number

[0078] where 2L represents the number of CSI-RS ports and N represents the number of frequency-domain DFT vectors in the first frequency-domain DFT vector set.

[0079] In a possible implementation of the fifth or sixth aspect of the embodiment of the present application, the quantity of bits occupied by the SCI satisfies a sixth scheme, which is:

[0080]

number

[0081] where 2L represents the number of CSI-RS ports and N represents the number of frequency-domain DFT vectors in the first frequency-domain DFT vector set.

[0082] In a possible implementation of the fifth or sixth aspect of the embodiment of the present application, the number of bits occupied by the first information satisfies a seventh scheme, and the seventh scheme is as follows:

[0083]

number

[0084] where N represents the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors, and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors;

[0085]

number

[0086] represents the number of combinations of N to M items.

[0087] Based on the above technical solution, the first information indicates a second set of frequency-domain DFT vectors selected by the terminal device. When a circular shift is not performed on the frequency-domain DFT vectors, the first information of the terminal device includes a position indicator of the frequency-domain DFT vector corresponding to the strongest coefficient, so that the number of bits occupied by the first information is correlated with the number N of frequency-domain DFT vectors configured by the network device and the number M of frequency-domain DFT vectors selected by the terminal device, and N and M are represented by the seventh scheme using the number of bits. Therefore, the terminal device does not need to perform a circular shift on the frequency-domain DFT vectors, thereby reducing implementation complexity.

[0088] In a possible implementation of the fifth or sixth aspect of the embodiment of the present application, the number of bits occupied by the first information satisfies an eighth scheme, and this eighth scheme is:

[0089]

number

[0090] where N represents the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors, and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors;

[0091]

number

[0092] represents the number of combinations between N-1 and M-1 items.

[0093] Based on the above technical solution, the first information indicates a second set of frequency-domain DFT vectors selected by the terminal device. When the terminal device performs a circular shift on the first set of frequency-domain DFT vectors so that the index of the frequency-domain DFT vector corresponding to the strongest coefficient indicated by the SCI becomes 0, the terminal device assumes by default that the frequency-domain DFT vector corresponding to the strongest coefficient is definitely selected. Therefore, the number of bits occupied by the first information is correlated with the number N-1 of frequency-domain DFT vectors configured by the network device and from which the frequency-domain DFT vector corresponding to the strongest coefficient is removed, and the number M-1 of frequency-domain DFT vectors selected by the terminal device and from which the frequency-domain DFT vector corresponding to the strongest coefficient is removed, where N-1 and M-1 are indicated using the number of bits in the eighth scheme. Therefore, the bit overhead of the SCI is reduced.

[0094] In a seventh aspect of an embodiment of the present application, there is provided a communication device including a transceiver unit and a processing unit.

[0095] The transceiver unit is configured to receive first indication information, the first indication information indicating a first frequency-domain DFT vector set, a subset of the first frequency-domain DFT vector set including a second frequency-domain DFT vector set, and the first frequency-domain DFT vector set and a CSI-RS port selected by the terminal device correspond to the second spatial-frequency vector set.

[0096] The processing unit is configured to determine a strongest coefficient indicator SCI based on the first indication information, the SCI indicating a spatial frequency vector corresponding to a strongest coefficient of the second set of spatial frequency vectors.

[0097] The transceiver unit is further configured to transmit uplink control information UCI, the UCI including first information and SCI, the first information indicating a second frequency domain DFT vector set, and a priority of the first information in the UCI being lower than a priority of the SCI in the UCI.

[0098] Optionally, the priority of the first information in the UCI is lower than the priority of the SCI in the UCI, in other words, the priority of the SCI in the UCI is higher than the priority of the first information in the UCI.

[0099] Based on the above technical solution, in the UCI transmitted by the transceiver unit, the first information has a lower priority than the SCI. The first information indicates a second frequency-domain DFT vector set selected by the terminal device, and the SCI indicates a space-frequency vector corresponding to the strongest coefficient of the space-frequency vector set corresponding to the first frequency-domain DFT vector set configured by the network device and the CSI-RS port selected by the terminal device. In other words, the SCI indicates the space-frequency vector corresponding to the first frequency-domain DFT vector set configured by the network device and corresponding to the strongest coefficient, and there is no correlation between the SCI and the second frequency-domain DFT vector set selected by the terminal device so that the network device can obtain the weighting coefficient of the strongest space-frequency vector corresponding to the downlink channel based on the high-priority SCI included in the UCI. Therefore, when UCI reporting resources are limited, the terminal device feeds back at least the SCI so that the accuracy of the frequency-domain position corresponding to the SCI and determined by the network device based on the SCI can be improved, thereby ensuring the effectiveness of the precoding matrix as much as possible. In addition, when UCI reporting resources are limited, the terminal device may not need to feed back the first information, so that overhead can be reduced to a certain extent.

[0100] In an eighth aspect of an embodiment of the present application, there is provided a communication device, including a transmitting unit and a receiving unit.

[0101] The transmitting unit is configured to transmit first indication information, the first indication information indicating a first frequency-domain DFT vector set, a subset of the first frequency-domain DFT vector set including a second frequency-domain DFT vector set, and the first frequency-domain DFT vector set and a CSI-RS port selected by the terminal device correspond to the second space-frequency vector set.

[0102] The receiving unit is configured to receive uplink control information UCI, the UCI including first information and SCI, the SCI indicating a spatial-frequency vector corresponding to a strongest coefficient of a second spatial-frequency vector set, the first information indicating a second frequency-domain DFT vector set, and a priority of the first information in the UCI being lower than a priority of the SCI in the UCI.

[0103] Optionally, the priority of the first information in the UCI is lower than the priority of the SCI in the UCI, in other words, the priority of the SCI in the UCI is higher than the priority of the first information in the UCI.

[0104] Based on the above technical solution, in the UCI received by the receiving unit, the first information has a lower priority than the SCI. The first information indicates a second frequency-domain DFT vector set selected by the terminal device, and the SCI indicates a space-frequency vector corresponding to the strongest coefficient of the space-frequency vector set corresponding to the first frequency-domain DFT vector set configured by the network device and the CSI-RS port selected by the terminal device. In other words, the SCI indicates the space-frequency vector corresponding to the first frequency-domain DFT vector set configured by the network device and corresponding to the strongest coefficient, and there is no correlation between the SCI and the second frequency-domain DFT vector set selected by the terminal device so that the network device can obtain the weighting coefficient of the strongest space-frequency vector corresponding to the downlink channel based on the high-priority SCI included in the UCI. Therefore, when UCI reporting resources are limited, the terminal device feeds back at least the SCI so that the accuracy of the frequency-domain position corresponding to the SCI and determined by the network device based on the SCI can be improved, thereby ensuring the effectiveness of the precoding matrix as much as possible. In addition, when UCI reporting resources are limited, the terminal device may not need to feed back the first information, so that overhead can be reduced to a certain extent.

[0105] In a possible implementation of the seventh or eighth aspect of the embodiment of the present application, the number of bits occupied by the SCI is correlated with the number of frequency domain DFT vectors in the first frequency domain DFT vector set.

[0106] In a possible implementation of the seventh or eighth aspect of the embodiment of the present application, the number of bits occupied by the SCI is further correlated with the number of CSI-RS ports.

[0107] In a possible implementation of the seventh or eighth aspect of the embodiment of the present application, the quantity of bits occupied by the SCI satisfies a fifth scheme, which is:

[0108]

number

[0109] where 2L represents the number of CSI-RS ports, N represents the quantity of frequency-domain DFT vectors in the first frequency-domain DFT vector set.

[0110] In a possible implementation of the seventh or eighth aspect of the embodiment of the present application, the quantity of bits occupied by the SCI satisfies a sixth scheme, which is as follows:

[0111]

number

[0112] where 2L represents the number of CSI-RS ports and N represents the number of frequency-domain DFT vectors in the first frequency-domain DFT vector set.

[0113] In a possible implementation of the seventh or eighth aspect of the embodiment of the present application, the quantity of bits occupied by the first information satisfies a seventh scheme, and the seventh scheme is as follows:

[0114]

number

[0115] where N represents the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors, and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors;

[0116]

number

[0117] represents the number of combinations of N to M items.

[0118] In a possible implementation of the seventh or eighth aspect of the embodiment of the present application, the quantity of bits occupied by the first information satisfies an eighth scheme, and this eighth scheme is:

[0119]

number

[0120] where N represents the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors, and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors;

[0121]

number

[0122] represents the number of combinations between N-1 and M-1 items.

[0123] For a description of several possible implementations of the seventh and eighth aspects and corresponding technical effects, see 5 The aspects and 6 Please note that reference is made to the above description of multiple possible implementations of the aspect and the corresponding technical effects, and the details will not be described again herein.

[0124] In a ninth aspect of an embodiment of the present application, there is provided a communication device including at least one logic circuit and an input / output interface.

[0125] The input / output interface is configured to output the UCI.

[0126] The logic circuit is configured to perform a method according to the first aspect or any one of the possible implementations of the first aspect.

[0127] In a tenth aspect of an embodiment of the present application, there is provided a communication device including at least one logic circuit and an input / output interface.

[0128] The input / output interface is configured to input the UCI.

[0129] The logic circuit is configured to perform a method according to the second aspect or any one of the possible implementations of the second aspect.

[0130] In an eleventh aspect of an embodiment of the present application, there is provided a communication device including at least one logic circuit and an input / output interface.

[0131] The input / output interface is configured to output the UCI.

[0132] The logic circuit is configured to perform a method according to the fifth aspect or any one of the possible implementations of the fifth aspect.

[0133] In a twelfth aspect of an embodiment of the present application, there is provided a communication device including at least one logic circuit and an input / output interface.

[0134] The input / output interface is configured to input the UCI.

[0135] The logic circuit is configured to perform a method according to the sixth aspect or any one of the possible implementations of the sixth aspect.

[0136] In a thirteenth aspect of the present application, there is provided a computer-readable storage medium storing one or more computer-executable instructions, wherein, when the computer-executable instructions are executed by a processor, the processor performs a method according to the first aspect or any one of the possible implementations of the first aspect; when the computer-executable instructions are executed by the processor, the processor performs a method according to the second aspect or any one of the possible implementations of the second aspect; when the computer-executable instructions are executed by the processor, the processor performs a method according to the fifth aspect or any one of the possible implementations of the fifth aspect; or when the computer-executable instructions are executed by the processor, the processor performs a method according to the sixth aspect or any one of the possible implementations of the sixth aspect.

[0137] In a fourteenth aspect of the present application, there is provided a computer program product (also referred to as a computer program) storing one or more computer-executable instructions. When the computer program product is executed by a processor, the processor performs the method according to the first aspect or any one of the possible implementations of the first aspect; when the computer program product is executed by the processor, the processor performs the method according to the second aspect or any one of the possible implementations of the second aspect; when the computer program product is executed by the processor, the processor performs the method according to the fifth aspect or any one of the possible implementations of the fifth aspect; or when the computer program product is executed by the processor, the processor performs the method according to the sixth aspect or any one of the possible implementations of the sixth aspect.

[0138] In a fifteenth aspect of an embodiment of the present application, there is provided a chip system, the chip system including at least one processor configured to support a terminal device in performing functions of the first aspect or any one of possible implementations of the first aspect, or configured to support a terminal device in performing functions of the fifth aspect or any one of possible implementations of the fifth aspect.

[0139] In a possible design, the chip system may further include a memory configured to store program instructions and data required for the terminal device. The chip system may include a chip, or may include a chip and other individual components. Optionally, the chip system may further include an interface circuit. The interface circuit provides the program instructions and / or data to the at least one processor.

[0140] In a sixteenth aspect of the present application, there is provided a chip system, the chip system including at least one processor configured to support a network device in performing functions of the second aspect or any one of possible implementations of the second aspect, or configured to support a network device in performing functions of the sixth aspect or any one of possible implementations of the sixth aspect.

[0141] In a possible design, the chip system may further include a memory configured to store program instructions and data required for the network device. The chip system may include a chip, or may include a chip and other individual components. Optionally, the chip system may further include an interface circuit. The interface circuit provides the program instructions and / or data to the at least one processor.

[0142] In a seventeenth aspect of an embodiment of the present application, there is provided a communication system, 3 The terminal device and the 4a communication system including a terminal device of the seventh aspect and a network device of the eighth aspect; a communication system including a terminal device of the ninth aspect and a network device of the tenth aspect; or a communication system including a terminal device of the eleventh aspect and a network device of the twelfth aspect.

[0143] For technical effects provided by any design scheme from the ninth aspect to the seventeenth aspect, please refer to the technical effects provided by different implementations of the first aspect, the second aspect, the fifth aspect, or the sixth aspect, and the details will not be described again in this specification.

[0144] It should be understood that with respect to device components, the foregoing "send" may be referred to as "output" and the foregoing "receive" may be referred to as "input."

[0145] From the above technical solution, it can be seen that in the UCI transmitted by the terminal device, the priority of the first information is the same as the priority of the SCI. The first information indicates a second frequency-domain DFT vector set selected by the terminal device, and the SCI indicates a space-frequency vector corresponding to the strongest coefficient of the space-frequency vector set corresponding to the second frequency-domain DFT vector set and the CSI-RS port selected by the terminal device. In other words, the SCI indicates the space-frequency vector corresponding to the second frequency-domain DFT vector set selected by the terminal device and corresponding to the strongest coefficient. Thus, the network device obtains a weighting coefficient of the strongest space-frequency vector corresponding to the downlink channel based on the SCI and the first information, which have the same priority and are included in the UCI. Therefore, when UCI reporting resources are limited, the terminal device feeds back at least the SCI and the first information indicating the second frequency-domain DFT vector set, so that the accuracy of the frequency-domain position corresponding to the SCI and determined by the network device based on the SCI and the first information is improved to ensure the effectiveness of the precoding matrix as much as possible. [Brief explanation of the drawings]

[0146] [Figure 1] 1 is a schematic diagram of a communication system according to the present application; [Figure 2] 1 is a schematic diagram of a channel information feedback method according to the present application; [Figure 3] FIG. 2 is a schematic diagram of reporting SCI by a UE and determining SCI by a base station according to the present application; [Figure 4] FIG. 10 is another schematic diagram of reporting SCI by a UE and determining SCI by a base station according to the present application; [Figure 5] 1 is a schematic diagram of a channel information feedback method according to the present application; [Figure 6] 1 is a schematic diagram of a terminal device according to the present application; [Figure 7]1 is a schematic diagram of a network device according to the present application; [Figure 8] FIG. 2 is another schematic diagram of a terminal device according to the present application; [Figure 9] FIG. 2 is another schematic diagram of a network device according to the present application. DETAILED DESCRIPTION OF THE INVENTION

[0147] The technical solutions in the embodiments of the present application are described below with reference to the accompanying drawings of the embodiments of the present application. It is clear that the described embodiments are only a part, not all, of the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present application.

[0148] 1 is a schematic diagram of a possible network architecture to which the present application is applicable, including a network device and at least one terminal device. The network device and the terminal device may operate in a new radio (NR) communication system, and the terminal device may communicate with the network device via the NR communication system. The network device and the terminal device may also operate in another communication system. This is not limited in the embodiments of the present application.

[0149] A terminal device may be a wireless terminal device capable of receiving scheduling information and indication information from a network device. A wireless terminal device may be a device providing voice and / or data connectivity to a user, a handheld device with wireless connectivity, or another processing device connected to a wireless modem. A wireless terminal device may communicate with one or more core networks or the Internet via a radio access network (RAN). A wireless terminal device may be a mobile terminal device such as a mobile (also called a "cellular" or mobile phone), a computer, or a data card, e.g., a portable, pocket-sized, handheld, computer-integrated, or vehicle-mounted mobile device that exchanges voice and / or data with a radio access network. For example, a wireless terminal device may be a personal communication service (PCS) phone, a cordless telephone set, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), a pad, or a computer with wireless transceiver functionality.A wireless terminal device may also be referred to as a system, a subscriber unit, subscriber station, mobile station (MS), remote station, access point (AP), remote terminal device, access terminal device, user terminal device, user agent, subscriber station (SS), customer premises equipment (CPE), terminal, user equipment (UE), mobile terminal (MT), etc. Alternatively, the wireless terminal device may be a wearable device, or a terminal device of a next generation communication system, e.g., a terminal device of a 5G network, a terminal device of a future evolved public land mobile network (PLMN), or a terminal device of an NR communication system.

[0150] The network device is an entity configured to transmit or receive signals on the network side, such as a next generation NodeB (gNodeB). The network device may be a device configured to communicate with a mobile device. The network device may be an AP in a wireless local area network (WLAN), a base transceiver station (BTS) in a global system for mobile communications (GSM) or code division multiple access (CDMA), a NodeB (NB) in a wideband code division multiple access (WCDMA), an evolved NodeB (eNB or eNodeB) in long term evolution (LTE), a relay station, an access point, an in-vehicle device, a wearable device, a network device in a 5G network, a network device in a future evolved public land mobile network (PLMN), a gNodeB in an NR system, etc. Additionally, in an embodiment of the present application, a network device provides a service to a cell, and a terminal device communicates with the network device using a transmission resource (e.g., a frequency domain resource also referred to as a spectrum resource) used by the cell. The cell may be a cell corresponding to a network device (e.g., a base station). The cell may belong to a macro base station or may belong to a base station corresponding to a small cell. The small cell herein may include a metro cell, a micro cell, a pico cell, a femto cell, etc.These small cells are characterized by a small coverage area and low transmission power and are applicable to providing high-speed data transmission services. In addition, in other possible cases, the network device may be another device that provides wireless communication capabilities to terminal devices. The specific technology used by the network device and the specific device form are not limited in the embodiments of the present application. For ease of explanation, in the embodiments of the present application, the device that provides wireless communication capabilities to terminal devices is referred to as the network device.

[0151] It should be understood that FIG. 1 is merely an example of a communication system of the present application.

[0152] To facilitate understanding of the embodiments of the present application, the following first provides a brief explanation of the terms used in the embodiments of the present application.

[0153] 1. Precoding Technique: When the channel state is known, a network device may process a signal to be transmitted using a precoding matrix that matches the channel, and then transmit the processed signal so that the precoded transmission signal adapts to the channel. Therefore, compared with the process in which a receiving device receives a non-precoded transmission signal and removes inter-channel effects, the complexity of the process in which a receiving device receives a precoded transmission signal and removes inter-channel effects is reduced. Therefore, a precoding process is performed on a signal to be transmitted so that the received signal quality (e.g., signal-to-interference plus noise ratio (SINR)) is improved. By using the precoding technique, a transmitting device may further transmit to multiple receiving devices using the same time-frequency resource; in other words, multi-user multiple-input multiple-output (MU-MIMO) is implemented. It should be noted that the related description of the precoding technique is merely an example for ease of understanding and does not limit the scope of protection of the embodiments of the present application. In a specific implementation process, a transmitting device may perform precoding in a different manner. For example, if channel information (e.g., but not limited to, a channel matrix) cannot be known, precoding is performed using a preset precoding matrix or a weighting processing scheme, the specifics of which are not described herein for the sake of brevity.

[0154] 2. Precoding Matrix Indicator (PMI): May indicate a precoding matrix. The precoding matrix may be, for example, a precoding matrix determined by a terminal device based on a channel matrix in a frequency domain unit. The channel matrix may be determined by the terminal device through channel estimation or the like, or based on channel reciprocity. However, it should be understood that a specific method for determining a precoding matrix by a terminal device is not limited to the above description. For specific implementations, please refer to the prior art. For the sake of brevity, implementations are not listed in this specification.

[0155] For example, the precoding matrix may be obtained by performing singular value decomposition (SVD) on the channel matrix or the covariance matrix of the channel matrix, or by performing eigenvalue decomposition (EVD) on the covariance matrix of the channel matrix. It should be understood that the above-listed methods for determining the precoding matrix are merely examples and do not constitute any limitation to the present application. For methods for determining the precoding matrix, please refer to the prior art. For the sake of brevity, the methods will not be listed here.

[0156] It should be noted that according to the method provided in the embodiment of the present application, the network device may determine the combination coefficients of the CSI-RS port, the frequency-domain DFT vector, and the space-frequency vector used to construct the precoding vector based on the feedback of the terminal device, and may also determine a precoding matrix corresponding to each frequency-domain unit. The precoding matrix may be directly used for downlink data transmission. Alternatively, several beamforming methods, including, for example, zero forcing (ZF), regularized zero forcing (RZF), minimum mean square error (MMSE), and maximum signal-to-leakage-and-noise ratio (SLNR), may be implemented to obtain the precoding matrix finally used for downlink data transmission. This is not limited in the present application. Unless otherwise described, all precoding matrices in the following description may be precoding matrices determined based on the method provided in the present application.

[0157] The precoding matrix determined by the terminal device may be understood as a precoding matrix to be fed back. The terminal device may use the PMI to indicate the precoding matrix to be fed back, so that the network device reconstructs the precoding matrix based on the PMI. It may be understood that the reconstructed precoding matrix obtained by the network device based on the PMI may be the same as or similar to the precoding matrix to be fed back.

[0158] In downlink channel measurements, a high degree of similarity between the precoding matrix determined by the network device based on the PMI and the precoding matrix determined by the terminal device indicates that the precoding matrix determined by the network device for data transmission can adapt to channel conditions to a greater extent, and thus received signal quality can be improved.

[0159] 3. Precoding Vector: A precoding matrix may include one or more vectors, e.g., column vectors. A precoding matrix may be used to determine one or more precoding vectors.

[0160] When there is one spatial layer and one polarization direction of the transmitting antenna, the precoding matrix is ​​a precoding vector. When there are multiple spatial layers and one polarization direction of the transmitting antenna, the precoding vector can be a component of the precoding matrix in the spatial layer. When there is one spatial layer and multiple polarization directions of the transmitting antenna, the precoding vector can be a component of the precoding matrix in the polarization direction. When there are multiple spatial layers and multiple polarization directions of the transmitting antenna, the precoding vector can be a component of the precoding matrix in the spatial layer and the polarization direction.

[0161] It should be understood that the precoding vectors may alternatively be determined by, for example, a vector of precoding matrices obtained by performing a mathematical transformation on the vector of precoding matrices, and the mathematical transformation relationship between the precoding matrices and the precoding vectors is not limited in this application.

[0162] 4. Antenna port: Sometimes called a port for short. An antenna port may be understood as a transmit antenna identified by a receiving device or capable of being distinguished in space. One antenna port may be pre-configured for each virtual antenna, where each virtual antenna may be a weighted combination of multiple physical antennas, and each antenna port may correspond to one reference signal. Therefore, each antenna port may be called a reference signal port, for example, a CSI-RS port or a sounding reference signal (SRS) port.

[0163] 5. Spatial domain vector: Also called a beam vector, a spatial domain beam basis vector, or a spatial domain basis vector. The elements of the spatial domain vector may represent the weights of the antenna ports. The signals of the antenna ports are linearly superimposed based on the weights represented by the elements of the spatial domain vector of the antenna ports so that a strong signal region can be formed in a specific direction in space.

[0164] The length of the space domain vector is the number of transmit antenna ports in the polarization direction, N s where N s ≧1 and is an integer. A spatial domain vector is, for example, of length N s It can be a column vector or a row vector, where .times. ...

[0165] Optionally, the spatial domain vectors are obtained from a discrete Fourier transform (DFT) matrix. Each column vector of the DFT matrix may be referred to as a spatial domain DFT vector. In other words, the spatial domain vectors may be DFT vectors. The spatial domain vectors may be, for example, DFT vectors defined in the type II codebook of the NR protocol TS38.214 release 15 (R15).

[0166] 6. Spatial domain vector set: may contain multiple spatial domain vectors of different lengths to correspond to different amounts of antenna ports. In an embodiment of the present application, the length of the spatial domain vector is N s Therefore, the lengths of all spatial domain vectors in the spatial domain vector set to which the spatial domain vector reported by the terminal device belongs are N s is.

[0167] In a possible design, the spatial domain vector set is N s may contain spatial domain vectors, and these N s The spatial domain vectors may be orthogonal to each other. Each spatial domain vector in the spatial domain vector set may be obtained from a two-dimensional (2D) DFT matrix. 2D may represent two different directions, for example, horizontal and vertical. If the number of antenna ports in the horizontal direction is N1 and the number of antenna ports in the vertical direction is N2, then N s =N1N2.

[0168] N s The spatial domain vectors are, for example,

[0169]

number

[0170] ,

[0171]

number

[0172] , and

[0173]

number

[0174] The matrix U s is N smay be constructed based on spatial domain vectors, where

[0175]

number

[0176] Each spatial domain vector in the spatial domain vector set is a 2D-DFT matrix

[0177]

number

[0178] (D N is an N×N orthogonal DFT matrix), the element in the mth row and nth column is

[0179]

number

[0180] In another possible design, the spatial domain vector set is s Using O s ×N s In this case, the spatial domain vector set is s subsets, each of which may contain N s Each subset may contain N spatial domain vectors. s The spatial domain vectors may be orthogonal to each other. Each spatial domain vector in the spatial domain vector set may be obtained from an oversampled 2D-DFT matrix. The oversampling factor O s is a positive integer. Specifically, O s = O1 × O2, where O1 may be the horizontal oversampling factor and O2 may be the vertical oversampling factor. O1 ≥ 1, O2 ≥ 1, O1 and O2 cannot be 1 at the same time, and both are integers.

[0181] Spatial domain vector set No. o s (0≦o s ≦Os-1, and o s is an integer) subset of N s Each of the spatial domain vectors can be expressed as, for example,

[0182]

number

[0183] ,

[0184]

number

[0185] , ..., and

[0186]

number

[0187] In this case, the matrix

[0188]

number

[0189] is the o s N subsets of s may be constructed based on spatial domain vectors, where

[0190]

number

[0191] is.

[0192] 7. Frequency domain unit: A unit of frequency domain resources, which may represent different frequency domain resource granularities. The frequency domain unit may include, but is not limited to, a resource block (RB), a subcarrier, a resource block group (RBG), or a precoding resource block group (PRG). In addition, the frequency domain length of one frequency domain unit may alternatively be one RB.

[0193] In an embodiment of the present application, the precoding matrix corresponding to the frequency domain unit may be a precoding matrix determined by performing channel measurement and feedback based on a reference signal in the frequency domain unit. The precoding matrix corresponding to the frequency domain unit may be used to precode data subsequently transmitted in the frequency domain unit. In the following description, the precoding matrix or precoding vector corresponding to the frequency domain unit may also be referred to as a precoding matrix or precoding vector of the frequency domain unit for short.

[0194] 8. Frequency domain vector: A vector that can represent the change pattern of a channel in the frequency domain. The frequency domain vector may be called a frequency domain DFT vector or an oversampled frequency domain DFT vector. In the following, only an example in which the frequency domain vector is a frequency domain DFT vector will be used. It should be understood that the frequency domain DFT vector below may also be expressed as an oversampled DFT vector, a frequency domain shift vector, a frequency domain vector, etc.

[0195] Each frequency-domain DFT vector can represent one variation law. When transmitted through a wireless channel, a signal may travel multiple paths from the transmit antenna to the receive antenna. Multipath delays cause frequency-selective fading, i.e., frequency-domain channel variations. Therefore, variation laws of the frequency-domain channel caused by delays on different transmission paths can be represented using different frequency-domain DFT vectors.

[0196] The length of the frequency-domain DFT vector may be determined by the number of frequency-domain units to be reported preconfigured in the reporting band, by the length of the reporting band, or by a value predefined in the protocol. The length of the frequency-domain DFT vector is not limited in this application. The reporting band may be, for example, a CSI reporting band (csi-ReportingBand) carried in a preconfigured manner reported using channel state information (CSI) of higher layer signaling (e.g., radio resource control (RRC) messages).

[0197] Frequency domain DFT vector u f The length of N f where N f is a positive integer. The frequency domain DFT vector is, for example, of length N f It can be a column vector or a row vector, where .times. ...

[0198] 9. Frequency domain DFT vector set: may contain multiple frequency domain DFT vectors of different lengths. In an embodiment of the present application, the length of the frequency domain DFT vector is N f Therefore, the lengths of the frequency-domain DFT vectors in the frequency-domain DFT vector set to which the frequency-domain DFT vector reported by the terminal device belongs are all N f is.

[0199] In a possible design, the frequency domain DFT vector set is N f may contain N frequency domain DFT vectors. f The frequency-domain DFT vectors may be orthogonal to one another. Each frequency-domain DFT vector in the frequency-domain DFT vector set may be obtained from a DFT matrix or an inverse discrete Fourier transformation (IDFT) matrix (the conjugate transpose of the DFT matrix).

[0200] N f The frequency domain DFT vectors are, for example,

[0201]

number

[0202] ,

[0203]

number

[0204] , ..., and

[0205]

number

[0206] The matrix U f But, N f may be constructed based on frequency domain DFT vectors, where

[0207]

number

[0208] is.

[0209] In another possible design, the frequency domain DFT vector set is fUsing O f ×N f frequency-domain DFT vectors. In this case, the frequency-domain DFT vector set is f Contains subsets, each of which is N f Each subset contains N frequency-domain DFT vectors. f The frequency-domain DFT vectors may be orthogonal to one another. Each frequency-domain DFT vector in the set of frequency-domain DFT vectors may be obtained from an oversampled DFT matrix or the conjugate transpose of an oversampled DFT matrix. The oversampling factor O f is a positive integer.

[0210] The oth frequency domain DFT vector set f (0≦o f ≦Of-1, o f is an integer) is included in the subset of N f The frequency domain DFT vectors are each, for example,

[0211]

number

[0212] ,

[0213]

number

[0214] , ..., and

[0215]

number

[0216] In this case, the matrix

[0217]

number

[0218] is the o f N subsets of s pieces Frequency domain DFT vector, where

[0219]

number

[0220] is.

[0221] Therefore, each frequency-domain DFT vector in the frequency-domain DFT vector set may be obtained from the DFT matrix or an oversampled DFT matrix, or from the conjugate transpose of the DFT matrix or the conjugate transpose of the oversampled DFT matrix. Each column vector in the frequency-domain DFT vector set may be referred to as a frequency-domain DFT vector or an oversampled frequency-domain DFT vector. In other words, the frequency-domain DFT vector may be an oversampled frequency-domain DFT vector.

[0222] 10. Spatial-frequency vector: Also called a joint spatial-frequency vector, a pair of spatial-frequency vectors, or a spatial-frequency basis vector, it is a vector that can represent the change pattern of the channel in the joint spatial-frequency domain. In the embodiment of the present application, when the channel is a single-polarization channel, the dimension of the joint spatial-frequency vector matrix is ​​((M1×M2)×N sb ) × A, where M1 is the number of horizontal transmit antenna ports of the network device, M2 is the number of vertical transmit antenna ports of the network device, and N sb is the quantity in frequency units, and A is the quantity of paths. If the channel is a dual polarization channel, the dimension of the joint space-frequency vector matrix is ​​(2×(M1×M2)×N sb )×A.

[0223] Optionally, the combined spatial frequency vector may be a DFT vector.

[0224] 11. DFT vector: A new combined spatial-frequency vector is obtained after the frequency domain vector of the combined spatial-frequency vector is shifted according to the frequency domain shift vector, and corresponds to the same spatial domain vector and a different frequency domain vector compared with the original combined spatial-frequency vector. The frequency domain shift vector of the combined spatial-frequency vector can be a DFT vector.

[0225] 12. Weighting coefficients: Also called combination coefficients or projection coefficients, these represent the weights of the channels for the combined spatial frequency vector. The combined spatial frequency vector corresponds to a spatial domain vector and a frequency domain DFT vector. The weighting coefficients include amplitude and phase. Each weighting coefficient may include amplitude and phase. For example, the spatial frequency combination coefficients ae jθ where a is the amplitude and θ is the phase. As explained above, there is a one-to-one correspondence between the weighting coefficients and the vector pairs including the spatial domain vector and the frequency domain DFT vector obtained after the frequency domain DFT vector is shifted; in other words, each weighting coefficient corresponds to the spatial domain vector and the frequency domain DFT vector, or each weighting coefficient corresponds to one spatial domain vector and one frequency domain DFT vector.

[0226] The weighting coefficient with the largest amplitude in each spatial layer is called the strongest coefficient. The position indicator of the spatial frequency vector corresponding to the strongest coefficient is the strongest coefficient indicator (SCI).

[0227] Optionally, the SCI may indicate only the location of the CSI-RS port among the selected set of CSI-RS ports that corresponds to the space-frequency vector of the strongest coefficient. Alternatively, the SCI may indicate the location of the CSI-RS port among the selected set of CSI-RS ports that corresponds to the space-frequency vector of the strongest coefficient, and may also indicate the location of the frequency-domain DFT vector among the selected set of frequency-domain DFT vectors that corresponds to the space-frequency vector of the strongest coefficient.

[0228] Optionally, each spatial layer has the strongest coefficient, and therefore each spatial layer has an SCI, in other words, multiple spatial layers correspond to multiple SCIs.

[0229] 13. Spatial Layer: In MIMO, a spatial layer may be considered a data stream that can be transmitted separately. To improve the utilization of spectrum resources and improve the data transmission capacity of a communication system, a network device may transmit data to a terminal device using multiple spatial layers.

[0230] The number of spatial layers is the rank of the channel matrix. The terminal device may determine the number of spatial layers based on the channel matrix obtained by channel estimation. The precoding matrix may be determined based on the channel matrix. For example, the precoding matrix may be determined by performing SVD on the channel matrix or the covariance matrix of the channel matrix. In the SVD process, different spatial layers may be distinguished based on the magnitude of their eigenvalues. For example, the precoding vector determined by the eigenvector corresponding to the largest eigenvalue may correspond to the first spatial layer, and the precoding vector determined by the eigenvector corresponding to the smallest eigenvalue may correspond to the Rth spatial layer. In other words, the eigenvalues ​​corresponding to the first to Rth spatial layers are in descending order. Simply put, the R spatial layers are in descending order of strength from the first to Rth spatial layers.

[0231] It should be understood that distinguishing different spatial layers based on unique values ​​is merely a possible embodiment and does not constitute any limitation to the present application. For example, other criteria for distinguishing spatial layers may be predefined in the protocol. This is not a limitation of the present application.

[0232] 14. Configuration and Preconfiguration: In this application, both configuration and preconfiguration may be used. Configuration indicates that a base station / server transmits configuration information of some parameters or parameter values ​​to a terminal using a message or signaling so that the terminal determines parameters for communication or resources for transmission based on the values ​​or information. Similar to configuration, preconfiguration may be parameter information or parameter values ​​obtained by the base station / server and the terminal device through prior negotiation, or may be parameter information or parameter values ​​specified in a standard protocol and used by the base station / server or the terminal device, or may be parameter information or parameter values ​​pre-stored in the base station / server or the terminal device. This is not limited in this application. Furthermore, these values ​​and parameters may be changed or updated.

[0233] 15. Channel State Information (CSI) Report: Information used to describe channel attributes of a communication link and reported by a receiving end (e.g., a terminal device) of a wireless communication system to a transmitting end (e.g., a network device). The CSI report may include, but is not limited to, a precoding matrix indicator (PMI), a rank indicator (RI), a channel quality indicator (CQI), a channel state information reference signal (CSI-RS), a CSI-RS resource indicator (CRI), and a layer indicator (LI). It should be understood that the specific CSI content listed above is merely an example for illustration purposes and does not constitute any limitation to the present application. The CSI may include one or more of the above-listed items, or may include other information representing the CSI that is different from the above-listed items. This is not a limitation of the present application.

[0234] 16. Relevant definitions for mathematical symbols in this application include: (1)

[0235]

number

[0236] , which means rounding up A. (2)log a (b), which represents the logarithm of b when a is used as the base, and (3)

[0237]

number

[0238] , represents the quantity of combinations of B elements obtained from A elements.

[0239] For example, the terminal device reports the CSI to the network device.

[0240] A terminal device may report one or more CSI reports in one time unit (e.g., slot), and each CSI report may correspond to one CSI reporting setting condition. The CSI reporting setting condition may be determined, for example, based on a CSI reporting setting. The CSI reporting setting may indicate a time-domain behavior and a CSI report band, a format corresponding to a report quantity, etc. The time-domain behavior includes, for example, periodic, semi-persistent, and aperiodic time-domain behavior. The terminal device may generate one CSI report based on one CSI reporting setting.

[0241] As described above, the present application may be applied to a 5G communication system or a next-generation system of a 5G communication system. Here, an example in which the present application is applied to a 5G communication system is used for explanation. The 5G communication system has higher requirements for system capacity, spectral efficiency, etc. In the 5G communication system, massive multiple-input multiple-output (Massive MIMO) technology plays an important role in the spectral efficiency of the system. When MIMO technology is used, the network device needs to perform modulation and coding and signal precoding when transmitting data to a terminal device. How to transmit data to the terminal device needs to depend on channel state information fed back by the terminal device to the network device.

[0242] In the following, an example will be described in which the network device is a base station and the terminal device is a UE. The procedure in which the UE reports CSI to the base station may be shown in Figure 2. It should be understood that Figure 2 is just an example of obtaining CSI by the base station.

[0243] In FIG. 2, the procedure for the UE to report CSI to the base station includes the following steps:

[0244] Step 1: The base station sends channel measurement configuration information.

[0245] Step 2: The base station transmits a reference signal (RS) used for channel measurement.

[0246] Step 3: The UE performs measurement based on the RS to obtain a measurement result, and feeds back a CSI report indicating the measurement result to the base station (for example, the CSI report is carried by the UCI). For example, the CSI report includes xxxx.

[0247] Step 4: The base station transmits data based on the CSI report fed back by the UE.

[0248] In step 4, the base station determines the number of spatial layers for transmitting data to the UE based on the RI of the CSI report fed back by the UE in step 3; the base station determines the modulation order and the channel coding bit rate for transmitting data to the UE based on the CQI of the CSI report fed back by the UE in step 3; and the base station determines the precoding matrix for transmitting data to the UE based on the PMI of the CSI report fed back by the UE in step 3.

[0249] Specifically, the PMI included in the CSI report is selected and reported based on a set of codebooks. In other words, the information bits corresponding to the PMI reported by the UE include a selection result obtained by the UE through channel measurements. This selection result may include one or more of the following parameters: frequency-domain indication information indicating a selected frequency-domain DFT vector; spatial-domain indication information indicating a selected CSI-RS port; a strongest coefficient indicator (SCI) indicating a space-frequency vector corresponding to the strongest coefficient among the set of selected space-frequency vectors; weighting factors for the space-frequency vector; and the position of the weighting factor in the codebook.

[0250] The SCI of the PMI is used as an example. In the codebook of the R16 standard release, the SCI is only the index of the CSI-RS port corresponding to the strongest coefficient among the set of selected CSI-RS ports, and

[0251]

number

[0252] Shows.

[0253]

number

[0254] represents rounding up log2(2L), where 2L is the number of CSI-RS ports in the set of CSI-RS ports selected by the terminal device from the set of P CSI-RS ports, and P is greater than or equal to 2L.

[0255] It should be noted that in the codebook of the R16 standard release, one CSI-RS port is correlated with one spatial domain vector, and in particular the parameter, i.e., CSI-RS port, is a concept of spatial domain dimension and does not encompass the frequency domain dimension.

[0256] Furthermore, the base station may further include resources to be used by the UE to carry UCI in the channel measurement configuration information in step 1 shown in FIG. 2 (or in other configuration information different from the channel measurement configuration information in step 1 shown in FIG. 2). In other words, the base station allocates resources to be used to carry UCI to the UE based on the configuration information. In addition, when uplink resources are limited due to low channel quality, a large number of UEs communicating with the base station, etc., the resources to be used to carry UCI and allocated to the UE by the base station may be insufficient. In this case, in step 3, when the UE needs to discard some information carried in the UCI, the current standard sets priorities for different parameters carried in the UCI to ensure that the UE feeds back more important channel information in the limited feedback space.

[0257] The following describes the setting of the priority of different parameters in the current UCI using an implementation example. The setting of the priority of different parameters in the current UCI is configured based on the premise that the universal set of frequency-domain DFT vectors configured by the base station is the frequency-domain DFT vector that can be selected by the UE.

[0258] On the other hand, when weighting coefficient feedback is implemented, in order to reduce feedback overhead, for the weighting coefficients of the space-frequency vectors fed back in step 3 shown in Figure 2, the UE normalizes the strongest coefficient to 1, does not report the amplitude and phase information of the strongest coefficient, and uses the strongest coefficient as a reference to report the relative amplitude and phase information of the other weighting coefficients.

[0259] For example, the strongest coefficient of the spatial layer is

[0260]

number

[0261] and another weighting factor for the spatial layer is

[0262]

number

[0263] After the strongest coefficient of the spatial layer is normalized to 1, the relative amplitude of another weighting coefficient x2 of the spatial layer is A2 / A1. phase is θ2-θ1. In addition, the strongest coefficient may indicate a weight value corresponding to the strongest spatial frequency vector selected by the UE. Therefore, the SCI indicating the location of the strongest coefficient is very important, thereby giving the SCI a higher priority during UCI.

[0264] On the other hand, in the codebook of the R16 standard release, one CSI-RS port is correlated with one spatial domain vector, and the UE may determine the frequency domain vector by selecting among a universal set of frequency domain DFT vectors.

[0265] For example, in the scenario shown in Figure 3, the universal set of frequency-domain DFT vectors is 64 frequency-domain DFT vectors (with index values ​​from 0 to 63). In Figure 3, rectangular boxes (including rectangular boxes filled with diagonal lines, rectangular boxes filled with blank spaces, and rectangular boxes filled with horizontal lines) indicate the locations of weighting coefficients, the horizontal coordinate axis represents the frequency-domain DFT vector index (from 0 to 63) corresponding to the weighting coefficients, and the vertical coordinate axis represents the CSI-RS port index (the values ​​of the CSI-RS port index are not shown in Figure 3).

[0266] It should be noted that the value range of the CSI-RS port index in Figure 3 is determined by the quantity (denoted as P) of CSI-RS ports corresponding to each spatial layer, and the weighting factors of the set of spatial frequency vectors selected by the UE correspond to 2L CSI-RS ports out of the P CSI-RS ports (2L is less than or equal to P). In other words, the weighting factors of the set of spatial frequency vectors selected by the UE correspond to the 2L CSI-RS ports. Additionally, in the example shown in Figure 3, 2L is equal to P.

[0267] Specifically, in the example of the left diagram shown in FIG. 3, the frequency-domain DFT vector indices corresponding to the weighting factors of the set of spatial-frequency vectors selected by the UE are 0, 2, 3, and 4, which correspond to the rectangular boxes filled with diagonal lines in the diagram. Correspondingly, the rectangular boxes filled with blanks are spatial-frequency vectors not selected by the UE, which correspond to, for example, frequency-domain DFT vector indices 1, 5, ..., and 63. In addition, the rectangular boxes filled with horizontal lines are the positions of the strongest coefficients, and the frequency-domain DFT vector index corresponding to the rectangular box is 3. For ease of explanation, hereinafter, the frequency-domain DFT vector corresponding to the weighting factors of the set of spatial-frequency vectors selected by the UE will be referred to as the selected frequency-domain DFT vector for short, and the CSI-RS port corresponding to the weighting factors of the set of spatial-frequency vectors selected by the UE will be referred to as the selected CSI-RS port for short.

[0268] Next, the UE performs a cyclic shift to shift the index of the frequency-domain DFT vector corresponding to the strongest coefficient to 0, so that the originally selected frequency-domain DFT vector changes from indexes 0, 2, 3, and 4 to 61, 63, 0, and 1 in the right diagram of FIG. 3 , and feeds back the shifted related information to the base station via UCI. Therefore, the frequency-domain DFT vectors with indexes 61, 63, 0, and 1 are selected at the base station end as precoding bases based on the UCI fed back by the UE, while the indices of the frequency-domain DFT vectors actually selected by the UE are 0, 2, 3, and 4. Since the frequency-domain DFT vectors determined by the base station based on the UCI differ from the frequency-domain DFT vectors actually selected by the UE by three DFT vector phases, the precoding at the base station also differs by one linear phase. Specifically, this is equivalent to the precoding matrix corresponding to the PMI reported to the UE end via UCI differing by one fixed phase from the precoding matrix restored at the base station end. Multiplying the precoding matrix by a fixed phase does not affect the beam direction, and therefore the precoding accuracy is not affected.

[0269] In the implementation scenario shown in FIG. 3, the SCI does not need to include the index of the frequency-domain DFT vector corresponding to the strongest coefficient, but only the index of the CSI-RS port corresponding to the strongest coefficient. In addition, the CSI-RS port index indicates the specific position of the CSI-RS port corresponding to the strongest coefficient in the CSI-RS port selected by the UE. In other words, the index of the frequency-domain position of the SCI is 0 by default. Performing a linear shift on the universal set of frequency-domain DFT vector sets is equivalent to multiplying all frequency-domain DFT vectors in the universal set by the same phase difference. Therefore, the frequency-domain DFT vector determined by the base station differs from the frequency-domain DFT vector selected by the UE by one fixed phase difference. Specifically, this is equivalent to the precoding matrix corresponding to the PMI reported at the UE end differing by one fixed phase from the precoding matrix restored at the base station. Multiplying the precoding matrix by one fixed phase does not affect the beam direction. Therefore, precoding accuracy is not affected. In other words, the frequency domain DFT vector indicating the frequency domain information and corresponding to the strongest coefficient does not need to be indicated in the SCI, thereby reducing the overhead of the SCI such that the frequency domain indication information indicating the selected frequency domain DFT vector of the UCI has a lower priority than the priority of the SCI.

[0270] The following describes, using examples, the multiple pieces of information included in the UCI and the priorities of the multiple pieces of information.

[0271] In the current R16 standard release, UCI is mainly divided into Part I and Part II. Part I includes information such as the number of non-zero weighting factors selected by the UE (all non-zero weighting factors corresponding to one or more spatial layers), RI, and CQI. Part II is divided into three groups based on the importance of the information. Group 0 has the first priority, Group 1 has the second priority, and Group 2 has the lowest priority.

[0272] For example, in the R16 standard release, UCI Part II is as follows:

[0273] Group 0 includes at least the CSI-RS port indicator and the SCI for each spatial layer.

[0274] Group 1 is the frequency domain vector starting index M initial and a relative amplitude (the relative amplitude indicates the relative amplitude of the strongest coefficient in another polarization direction with respect to the strongest coefficient indicated by the SCI), and a first determined based on the priority.

[0275]

number

[0276] The amplitude of the weighting coefficient (the superscript "NZ" means non-zero, K NZ indicates the number of non-zero weighting factors), and the first

[0277]

number

[0278] The first one is determined based on the phase of the weighting coefficient and the priority.

[0279]

number

[0280] and a bitmap of weighting coefficients.

[0281] Note that in this and subsequent embodiments, ν denotes the number of spatial layers, 2L denotes the number of selected CSI-RS ports (if dual polarization directions are used, L CSI-RS ports are selected for each polarization direction), and M denotes the number of selected frequency-domain DFT vectors.

[0282] Group 2 is the last group to be prioritized.

[0283]

number

[0284] The amplitude of the weighting coefficient and the final

[0285]

number

[0286] The final weighting factor is determined based on the phase and priority.

[0287]

number

[0288] and a bitmap of weighting coefficients.

[0289] When uplink resources are limited due to poor channel quality, a large number of UEs communicating with the base station, or the like, resources used to carry UCI and allocated to UEs by the base station may be insufficient. In this case, the UE determines the information to be reported in Part II of UCI based on the priority of the groups. For example, when the number of UCI resources is small, the UE may report only the information included in Group 0; when UCI resources are more sufficient, the UE may report the information included in Group 0 and Group 1; when UCI resources are even more sufficient, the UE may report the information included in Group 0, Group 1, and Group 2. Therefore, in the current design of Part II of UCI, the highly important SCI and its correlated CSI-RS port indicator are placed in Group 0 with the highest priority, and the frequency-domain DFT vector indicator is placed in Group 1 with the second highest priority because the frequency-domain DFT vector indicator is not correlated with the SCI.

[0290] The above-described implementation process is an implementation process in which the UE performs selection based on a universal set of frequency-domain DFT vectors configured by the base station. However, for example, in the codebook of the R17 standard release, one CSI-RS port is correlated with one space-frequency domain vector (the space-frequency domain vector is sometimes referred to as a space-frequency vector for short). Specifically, the parameter, i.e., the CSI-RS port, encompasses not only the concept of the space-domain dimension but also the frequency-domain dimension. In addition, the base station configures only some frequency-domain DFT vectors for selection by the UE. In other words, the frequency-domain DFT vectors that can be selected by the UE are only a part of the universal set. In this scenario, the current UCI priority setting may not be applicable. The following description will be given using the implementation example shown in Figure 4.

[0291] For the meaning of parameters such as the rectangular box and horizontal coordinate axis shown in Figure 4, please refer to the description of Figure 3 above. The details will not be explained again here.

[0292] As shown in Figure 4, the universal set of frequency-domain DFT vectors still includes 64 frequency-domain DFT vectors, and the number of frequency-domain DFT vectors that can be selected by the UE and configured by the base station is N=6, in other words, it is assumed that selection can be performed at the UE side among only 6 frequency-domain DFT vectors given at the base station end.

[0293] In the example shown on the left side of FIG. 4, the frequency-domain DFT vectors provided by the base station have indices 0 to 5, and the frequency-domain DFT vectors selected by the UE have indices 2 and 3, corresponding to the rectangular boxes filled with diagonal lines. Accordingly, the blank rectangular boxes are spatial frequency vectors not selected by the UE, and correspond to frequency-domain DFT vector indices 0, 1, 4, and 5, for example. Additionally, the horizontally filled rectangular boxes indicate the positions of the strongest coefficients, and the frequency-domain DFT vector corresponding to the rectangular boxes has an index of 3. The UE performs a circular shift of six frequency-domain DFT vectors to allow the index of the frequency-domain DFT vector corresponding to the strongest coefficient to become 0 and reports the shifted information to the base station. Therefore, the indices of the frequency-domain DFT vectors determined by the base station based on UE feedback are changed to 0 and 5, and the frequency-domain DFT vectors actually selected by the UE have indices 2 and 3. Since the frequency domain DFT vectors determined by the base station based on the UCI do not differ from the frequency domain DFT vectors actually selected by the UE by more than one fixed DFT vector phase, the phase difference between the frequency domain DFT vector determined by the base station based on UE feedback and the frequency domain DFT vector actually selected at the UE end is different for the universal set of 64 frequency domain DFT vectors, resulting in the base station's precoding not differing by more than one linear phase. In other words, the phase differences between the frequency domain DFT vectors determined by the base station based on UE feedback and all of the frequency domain DFT vectors actually selected at the UE end are different, resulting in the frequency domain DFT vector determined by the base station not differing by more than one fixed phase from the frequency domain DFT vector selected by the UE. Therefore, it is not possible to ensure that the precoding matrix indicated at the UE end differs by more than one linear phase from the precoding matrix generated at the base station end.As a result, the beam directions indicated at the base station end based on the frequency-domain DFT vectors obtained after precoding and with indices 0 and 5 may not match the beam directions indicated by the frequency-domain DFT vectors obtained after precoding and selected at the UE end with indices 2 and 3. This affects the precoding accuracy.

[0294] From the example shown in FIG. 4, it can be seen that when a UE reports an SCI, it is truly necessary to indicate the index of the frequency-domain DFT vector with the strongest coefficient, which exists before the cyclic shift, regardless of whether the cyclic shift is performed on the frequency-domain DFT vector. However, with the current priority setting of UCI-related parameters, when the CSI report storage space allocated to the UE by the base station is insufficient, the UE may report only the SCI and not report the frequency-domain DFT vector indicator. As a result, the frequency-domain position of the SCI determined by the network device may be inaccurate, which may affect the accuracy of precoding performed by the network device based on the SCI, thereby affecting communication efficiency.

[0295] In addition, for example, in the codebook of the R16 standard release, if the universal set of frequency-domain DFT vectors configured by the base station is the frequency-domain DFT vector that can be selected by the UE, the frequency-domain DFT vector with index 0 is definitely selected by default, so that the frequency-domain DFT vector indicators of each spatial layer on the UE side are

[0296]

number

[0297] bits, where N3 represents the number of frequency domain DFT vectors that can be selected by the UE, and M i denotes the quantity of frequency-domain DFT vectors selected in the ith spatial layer,

[0298]

number

[0299] is the sum of M from N3-1 frequency domain DFT vectors. i -Select one frequency-domain DFT vector, in total

[0300]

number

[0301] In addition, to reduce overhead, when the value of N3 is greater than 19, the frequency domain DFT vector selection is performed at the UE side with the starting point being M initial And the length is

[0302]

number

[0303] may be implemented in a window of

[0304]

number

[0305] and the frequency domain DFT vector indicators for each layer on the UE side are

[0306]

number

[0307] bits. Therefore, when the value of N3 is greater than 19, M initial and frequency domain DFT vector indicators are also reportedly placed in Group 1 of Part II of the UCI.

[0308] For example, in the codebook of the R17 standard release, when the frequency domain DFT vectors that can be selected by the UE are part of the universal set of frequency domain DFT vectors configured by the base station, the quantity of that part of the frequency domain DFT vectors is usually a small value (e.g., 4, 6, or 8) and not greater than 19. Therefore, when the UE selects the parameter M initial It also determines whether the company needs to report the

[0309] The embodiments of the present application provide a channel information feedback method and a communication device, so that a network device obtains the strongest coefficient corresponding to a downlink channel based on the SCI and first information, which have the same priority and are included in the UCI. Therefore, when UCI reporting resources are limited, the terminal device feeds back at least the SCI and the first information indicating a second frequency-domain DFT vector set, so that the accuracy of the frequency-domain position corresponding to the SCI and determined by the network device based on the SCI and the first information is improved to ensure the effectiveness of the precoding matrix as much as possible.

[0310] 5 is a schematic diagram of a channel information feedback method according to an embodiment of the present application. The method includes the following steps:

[0311] S101: A network device transmits first indication information.

[0312] In this embodiment, the network device transmits first indication information in step S101, and in response, the terminal device receives the first indication information in step S101. The first indication information indicates a first frequency-domain DFT vector set, in other words, the first indication information indicates that a set of frequency-domain DFT vectors that can be selected by the terminal device is the first frequency-domain DFT vector set.

[0313] Specifically, the first frequency-domain DFT vector set includes the second frequency-domain DFT vector set, or in other words, the second frequency-domain DFT vector set is a subset or universal set of the first frequency-domain DFT vector set. The number of frequency-domain DFT vectors included in the first frequency-domain DFT vector set (denoted as N) is equal to or greater than the number of frequency-domain DFT vectors included in the second frequency-domain DFT vector set (denoted as M), or in other words, N≧M. In addition, the second frequency-domain DFT vector set may also be referred to as a (set) of frequency-domain DFT vectors selected by a (terminal device) or a (set) of frequency-domain DFT vectors selected by a terminal device.

[0314] In a possible implementation, the first indication information may be carried in a radio resource control (RRC) configuration message sent by the network device to the terminal device, or may be carried in a media access control (MAC CE) control element, or may be carried in another message / other signaling, which is not limited herein.

[0315] In a possible implementation, the first indication information may include an identifier of the first frequency-domain DFT vector set, or may include one or more of an index of the first frequency-domain DFT vector set and a quantity of frequency-domain DFT vectors included in the first frequency-domain DFT vector set, or may include other information that can enable the terminal device to determine the first frequency-domain DFT vector set, which is not limited herein.

[0316] In a possible implementation, in step S101, the network device may further transmit second indication information to the terminal device. The second indication information indicates the number M of frequency-domain DFT vectors included in the second frequency-domain DFT vector set. In other words, the second indication information indicates the number M of frequency-domain DFT vectors (second frequency-domain DFT vector set) that need to be selected by the terminal device from the set of frequency-domain DFT vectors (first frequency-domain DFT vector set) that can be selected by the terminal device. In other words, the second indication information indicates the number M of frequency-domain DFT vectors (second frequency-domain DFT vector set) selected by the terminal device from the set of frequency-domain DFT vectors (first frequency-domain DFT vector set) that can be selected by the terminal device.

[0317] Optionally, the second indication information includes the quantity of frequency-domain DFT vectors included in the second frequency-domain DFT vector set, or includes other information that can enable the terminal device to determine the quantity of frequency-domain DFT vectors included in the second frequency-domain DFT vector set, which is not limited herein.

[0318] Optionally, the second indication information may be included in the first indication information, specifically, in addition to indicating the first frequency domain DFT vector set, the first indication information further indicates a second frequency domain DFT vector set.

[0319] Optionally, the second indication information may be pre-configured in the terminal device.

[0320] In a possible implementation, in step S101, the network device may further send third indication information to the terminal device, where the third indication information indicates the first CSI-RS port set, in other words, the third indication information indicates that the set of CSI-RS ports that can be selected by the terminal device is the first CSI-RS port set.

[0321] Specifically, the first CSI-RS port set includes the second CSI-RS port set, or in other words, the second CSI-RS port set is a subset or universal set of the first CSI-RS port set. The quantity of CSI-RS ports included in the first CSI-RS port set (denoted as P) is equal to or greater than the quantity of CSI-RS ports included in the second CSI-RS port set (denoted as 2L), or in other words, P≧2L. In addition, the second CSI-RS port set may also be referred to as a (set) of CSI-RS ports selected by a (terminal device).

[0322] Optionally, the third indication information may be included in the first indication information, specifically, in addition to indicating the first frequency domain DFT vector set, the first indication information may also include: 1 1 further illustrates the CSI-RS port set of

[0323] Optionally, the third indication information may be pre-configured in the terminal device.

[0324] Optionally, the third indication information includes an identifier of the first CSI-RS port set, or the third indication information includes one or more of an index of the first CSI-RS port set and a quantity of CSI-RS ports included in the first CSI-RS port set, or the third indication information includes other information that can enable the terminal device to determine the first CSI-RS port set, which is not limited herein.

[0325] In a possible implementation, in step S101, the network device may further transmit fourth indication information to the terminal device. The fourth indication information indicates the quantity 2L of CSI-RS ports included in the second CSI-RS port set, in other words, the fourth indication information indicates the quantity 2L of CSI-RS ports (second CSI-RS port set) that need to be selected by the terminal device from the set of CSI-RS ports (first CSI-RS port set) that can be selected by the terminal device, in other words, the fourth indication information indicates the quantity 2L of CSI-RS ports (second CSI-RS port set) selected by the terminal device from the set of CSI-RS ports (first CSI-RS port set) that can be selected by the terminal device.

[0326] Similarly, the fourth indication information may include the number of CSI-RS ports included in the second CSI-RS port set, or may include other information that can enable the terminal device to determine the number of CSI-RS ports included in the second CSI-RS port set, which is not limited herein.

[0327] Optionally, the fourth indication information may be included in the first indication information, specifically, the first Frequency domain DFT vector In addition to indicating the set, the first indication information further indicates a second CSI-RS port set.

[0328] Optionally, the fourth indication information may be pre-configured in the terminal device.

[0329] From the above description, it can be seen that the first indication information may include any one or more of the second indication information, the third indication information, and the fourth indication information. Specifically, the first indication information may include any one or more of the second indication information, the third indication information, and the fourth indication information. Frequency domain DFT vectorIn addition to indicating the set, the first indication information may be found to further indicate other related information.

[0330] In a possible implementation, the network device indicates values ​​of parameters such as M or 2L by including an index or other indication information corresponding to a combination of one or more parameters, such as M (the number of frequency-domain DFT vectors included in the second frequency-domain DFT vector set) and / or 2L (the number of CSI-RS ports included in the second CSI-RS port set). In other words, the terminal device may determine values ​​of parameters such as M and / or 2L using an index or other indication information corresponding to a combination of one or more parameters and transmitted by the network device.

[0331] S102: The terminal device determines an SCI based on the first indication information.

[0332] In this embodiment, the terminal device determines the SCI based on the first indication information received in step S101.

[0333] Specifically, in step S102, the terminal device may determine a spatial-frequency vector corresponding to the strongest coefficient of the spatial-frequency vector set corresponding to the CSI-RS port based on the first frequency-domain DFT vector set indicated by the first indication information, determine an SCI based on the spatial-frequency vector corresponding to the strongest coefficient, and indicate the spatial-frequency vector corresponding to the strongest coefficient to the network device using the SCI in a later step S103.

[0334] In a possible implementation, in step S102, a space-frequency vector set including space-frequency vectors corresponding to the strongest coefficients may be jointly determined by the terminal devices based on the second frequency-domain DFT vector set and the set of CSI-RS port sets selected by the terminal devices, and is also referred to as the first space-frequency vector set; or, a space-frequency vector set including space-frequency vectors corresponding to the strongest coefficients may be jointly determined by the terminal devices based on the first frequency-domain DFT vector set and the set of CSI-RS ports selected by the terminal devices, and is also referred to as the second space-frequency vector set.

[0335] Additionally, in step S102, the terminal device may determine the SCI based on the first indication information in multiple implementations. For example, the terminal device may determine, as the space-frequency vector corresponding to the SCI, a space-frequency vector corresponding to the strongest coefficient of a first space-frequency vector set corresponding to a second frequency-domain DFT vector set including M frequency-domain DFT vectors, and the selected CSI-RS port indicated by the first indication information. In another example, the terminal device may determine, as the space-frequency vector corresponding to the SCI, a space-frequency vector corresponding to the strongest coefficient of a second space-frequency vector set corresponding to a first frequency-domain DFT vector set including N frequency-domain DFT vectors, and the selected CSI-RS port indicated by the first indication information. The implementation process will be described below using different embodiments.

[0336] Embodiment 1: In step S102, the terminal device determines, as the space-frequency vector corresponding to the SCI, the space-frequency vector corresponding to the strongest coefficient of the first space-frequency vector set corresponding to the second frequency-domain DFT vector set including M frequency-domain DFT vectors, and the CSI-RS port selected by (the terminal device) indicated by the first indication information.

[0337] In a possible implementation of embodiment 1, the number of bits occupied by the SCI determined by the terminal device in step S102 is correlated with the number of frequency domain DFT vectors in the second frequency domain DFT vector set. For example, the correlation indicates that the number of bits occupied by the SCI is positively correlated with the number of frequency domain DFT vectors in the second frequency domain DFT vector set. Specifically, the larger the number of frequency domain DFT vectors in the second frequency domain DFT vector set, the larger the number of bits occupied by the SCI. Conversely, the smaller the number of frequency domain DFT vectors in the second frequency domain DFT vector set, the smaller the number of bits occupied by the SCI.

[0338] Based on the above technical solution, the SCI indicates a spatial-frequency vector corresponding to the second frequency-domain DFT vector set selected by the terminal device and corresponding to the strongest coefficient. The SCI may use at least some occupied bits to indicate the position of the strongest coefficient of the second frequency-domain DFT vector set and the frequency-domain DFT vector selected by the terminal device.

[0339] In a possible implementation of embodiment 1, the number of bits occupied by the SCI determined by the terminal device in step S102 is further correlated with the number of CSI-RS ports. For example, the correlation indicates that the number of bits occupied by the SCI is positively correlated with the number of CSI-RS ports in the second CSI-RS port set. Specifically, a larger number of CSI-RS ports in the second CSI-RS port set indicates a larger number of bits occupied by the SCI, and conversely, a smaller number of CSI-RS ports in the second CSI-RS port set indicates a smaller number of bits occupied by the SCI.

[0340] Based on the aforementioned technical solution, the SCI indicates the space-frequency vector corresponding to the strongest coefficient of the first space-frequency vector set corresponding to the second frequency-domain DFT vector set selected by the terminal device and the selected CSI-RS port. The SCI may indicate the location of the strongest coefficient and of the CSI-RS port selected by the terminal device in the selected CSI-RS port using at least some occupied bits. Therefore, in subsequent processing after the network device receives the SCI, the network device determines, based on the SCI, the location of the CSI-RS port corresponding to the strongest coefficient among the CSI-RS ports selected by the terminal device.

[0341] In a possible implementation, the number of bits occupied by the SCI determined by the terminal device in step S102 satisfies a first scheme, and the first scheme is:

[0342]

number

[0343] where 2L represents the number of CSI-RS ports and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors.

[0344] In a possible implementation of embodiment 1, the number of bits occupied by the SCI determined by the terminal device in step S102 satisfies a second scheme, and the second scheme is as follows:

[0345]

number

[0346] where 2L represents the number of CSI-RS ports and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors.

[0347] Embodiment 2: In step S102, the terminal device determines, as the space-frequency vector corresponding to the SCI, a space-frequency vector corresponding to the strongest coefficient of a second space-frequency vector set corresponding to a first frequency-domain DFT vector set including N frequency-domain DFT vectors, and a CSI-RS port selected by the terminal device indicated by the first indication information.

[0348] In a possible implementation of embodiment 2, the number of bits occupied by the SCI is correlated with the number of frequency-domain DFT vectors in the first frequency-domain DFT vector set. For example, the correlation indicates that the number of bits occupied by the SCI is positively correlated with the number of frequency-domain DFT vectors in the first frequency-domain DFT vector set. Specifically, a larger number of frequency-domain DFT vectors in the first frequency-domain DFT vector set indicates a larger number of bits occupied by the SCI, and conversely, a smaller number of frequency-domain DFT vectors in the first frequency-domain DFT vector set indicates a smaller number of bits occupied by the SCI.

[0349] Based on the above technical solution, the SCI indicates a space-frequency vector corresponding to a first frequency-domain DFT vector set configured by the network device and corresponding to the strongest coefficient, and the SCI may use at least some occupied bits to indicate the position of the frequency-domain DFT vector of the strongest coefficient in the first frequency-domain DFT vector set selected by the terminal device.

[0350] In a possible implementation of embodiment 2, the number of bits occupied by the SCI is further correlated with the number of CSI-RS ports. For example, the correlation indicates that the number of bits occupied by the SCI is positively correlated with the number of CSI-RS ports in the second CSI-RS port set. Specifically, a larger number of CSI-RS ports in the second CSI-RS port set indicates a larger number of bits occupied by the SCI, and conversely, a smaller number of CSI-RS ports in the second CSI-RS port set indicates a smaller number of bits occupied by the SCI.

[0351] Based on the aforementioned technical solutions, SCI: network By device composition The SCI indicates a space-frequency vector corresponding to the strongest coefficient of the second space-frequency vector set corresponding to the first frequency-domain DFT vector set and the CSI-RS port selected by the terminal device. The SCI may indicate, using at least some of the reserved bits, the location of the CSI-RS port corresponding to the strongest coefficient and selected by the terminal device in the selected CSI-RS port. Thus, in subsequent processing after the network device receives the SCI, the network device determines, based on the SCI, the location of the CSI-RS port selected by the terminal device that corresponds to the strongest coefficient.

[0352] In a possible implementation of embodiment 2, the number of bits occupied by the SCI satisfies a fifth scheme, which is as follows:

[0353]

number

[0354] where 2L represents the number of CSI-RS ports and N represents the number of frequency-domain DFT vectors in the first frequency-domain DFT vector set.

[0355] In a possible implementation of embodiment 2, the number of bits occupied by the SCI satisfies a sixth scheme, which is as follows:

[0356]

number

[0357] where 2L represents the number of CSI-RS ports and N represents the number of frequency-domain DFT vectors in the first frequency-domain DFT vector set.

[0358] S103: The terminal device transmits UCI.

[0359] In this embodiment, the terminal device sends the UCI to the network device in step S103, and in response, the network device receives the UCI from the terminal device in step S103.

[0360] Specifically, the UCI includes the SCI and first information, and the priority of the SCI may be the same as or different from the priority of the first information. The SCI indicates a spatial frequency vector corresponding to the strongest coefficient of the first spatial frequency vector set. The first information indicates a second frequency domain DFT vector set, in other words, the first information indicates the position of a frequency domain DFT vector included in the second frequency domain DFT vector set among the first frequency domain DFT vector set, in other words, the first information indicates the index of a frequency domain DFT vector included in the second frequency domain DFT vector set among the first frequency domain DFT vector set.

[0361] In a possible implementation, the UCI sent by the terminal device in step S103 is a parameter M initialIn the codebook of the R16 standard release, the frequency domain DFT vectors that can be selected by the UE are a universal set of frequency domain DFT vectors. Therefore, when N is greater than a threshold (e.g., 19), the frequency domain DFT vector selection is performed by the UE, starting from M initial And the length is

[0362]

number

[0363] must be performed within a window of

[0364]

number

[0365] However, in the codebook of the R17 standard release, the frequency domain DFT vectors (first frequency domain DFT vector set) that can be selected by the UE are not a universal set of frequency domain DFT vectors. Therefore, the number of frequency domain DFT vectors (first frequency domain DFT vector set) that can be selected by the UE is small. Specifically, when the number of frequency domain DFT vectors in the first frequency domain DFT vector set indicated by the first indication information sent by the network device in step S101 is less than a predefined threshold, which may be 19, 18, 10, or another value, the UCI is set by the parameter M initial In response, the network device sets the parameter M initial There is no need to read it from the UCI.

[0366] In a possible implementation, the number of bits occupied by the first information sent by the terminal device in step S103 satisfies the following:

[0367]

number

[0368] where N represents the number of frequency-domain DFT vectors in the first frequency-domain DFT vector set, M represents the number of frequency-domain DFT vectors in the second frequency-domain DFT vector set, and

[0369]

number

[0370] represents the number of combinations of N to M items.

[0371] Based on the above technical solution, the first information indicates a second set of frequency-domain DFT vectors selected by the terminal device. When no cyclic shift is performed on the frequency-domain DFT vectors, the first information of the terminal device includes a position indicator of the frequency-domain DFT vector corresponding to the strongest coefficient, so that the number of bits occupied by the first information is correlated with the number N of frequency-domain DFT vectors configured by the network device and the number M of frequency-domain DFT vectors selected by the terminal device, and N and M are represented using the number of bits in this implementation. Therefore, the terminal device does not need to perform a cyclic shift on the frequency-domain DFT vectors, thereby reducing implementation complexity.

[0372] For example, an implementation of the number of bits occupied by the first information is described herein using an example where N=4 (the number of frequency-domain DFT vectors in the first frequency-domain DFT vector set is 4) and M=2 (the number of frequency-domain DFT vectors in the second frequency-domain DFT vector set is 2).

[0373] Specifically, when N=4 and M=2, there are six cases where two frequency-domain DFT vectors are selected from the frequency-domain DFT vectors with indices 0, 1, 2, and 3. In this case,

[0374]

number

[0375] and the information that can be indicated using the 3 bits occupied by the first information includes eight values: 000, 001, 010, 011, 100, 101, 110, and 111. To indicate the aforementioned six cases, only six of the eight values ​​may be used and two of the eight values ​​may be discarded, or two of the eight values ​​may be reused as indications of the same case, or another implementation may be used, which is not limited herein.

[0376] For example, only six of the eight values ​​(000, 001, 010, 011, 100, 101) are used, and two of the eight values ​​(110, 111) are discarded. For example, when the value of the three bits occupied by the first information is 000, it indicates that the frequency-domain DFT vectors with indices 0 and 1 are selected; when the value of the three bits occupied by the first information is 001, it indicates that the frequency-domain DFT vectors with indices 0 and 2 are selected; when the value of the three bits occupied by the first information is 010, it indicates that the frequency-domain DFT vectors with indices 0 and 3 are selected; when the value of the three bits occupied by the first information is 011, it indicates that the frequency-domain DFT vectors with indices 1 and 2 are selected; when the value of the three bits occupied by the first information is 100, it indicates that the frequency-domain DFT vectors with indices 1 and 3 are selected; or when the value of the three bits occupied by the first information is 101, it indicates that the frequency-domain DFT vectors with indices 2 and 3 are selected.

[0377] Optionally, the network device may send fifth indication information to the terminal device before step S103, and use this fifth indication information to indicate index values ​​corresponding to different values ​​of the number of bits occupied by the first information.

[0378] Optionally, the fifth indication information may be included in the first indication information in step S101, specifically, the first Frequency domain DFT vector In addition to indicating the set, the first indication information further indicates index values ​​corresponding to different values ​​of the quantity of bits occupied by the first information.

[0379] Optionally, the fifth indication information may be pre-configured in the terminal device.

[0380] In a possible implementation, the number of bits occupied by the first information sent by the terminal device in step S103 satisfies the following:

[0381]

number

[0382] where N represents the number of frequency-domain DFT vectors in the first frequency-domain DFT vector set, M represents the number of frequency-domain DFT vectors in the second frequency-domain DFT vector set, and

[0383]

number

[0384] represents the number of combinations between N-1 and M-1 items.

[0385] Based on the above technical solution, the first information indicates a second frequency-domain DFT vector set selected by the terminal device. When the terminal device performs a circular shift on the first frequency-domain DFT vector set to enable the index of the frequency-domain DFT vector corresponding to the strongest coefficient indicated by the SCI to become 0, the terminal device assumes by default that the frequency-domain DFT vector corresponding to the strongest coefficient is definitely selected. Compared with an implementation in which the terminal device performs a circular shift on a universal set of frequency-domain DFT vectors of a codebook of the R16 standard release, in this embodiment (e.g., during application to a codebook of the R17 standard release), the terminal device performs a circular shift on the first frequency-domain DFT vector set instead of performing a circular shift on the universal set of frequency-domain DFT vectors. Therefore, the number of bits occupied by the first information is correlated with the number N-1 of frequency-domain DFT vectors configured by the network device and from which the frequency-domain DFT vector corresponding to the strongest coefficient is removed, and the number M-1 of frequency-domain DFT vectors selected by the terminal device and from which the frequency-domain DFT vector corresponding to the strongest coefficient is removed, where N-1 and M-1 are represented using the number of bits in this implementation, thereby reducing the bit overhead of the SCI.

[0386] In a possible implementation, the SCI in the UCI transmitted by the terminal device in step S103 is implemented in step S102 based on the implementation of embodiment 1. Specifically, in the UCI, the priority of the first information is the same as the priority of the SCI. The first information indicates a second frequency-domain DFT vector set selected by the terminal device, and the SCI indicates a space-frequency vector corresponding to the strongest coefficient of the first space-frequency vector set, which corresponds to the second frequency-domain DFT vector set and the CSI-RS port selected by the terminal device. In other words, the SCI indicates the space-frequency vector corresponding to the second frequency-domain DFT vector set selected by the terminal device and the strongest coefficient, so that the network device obtains a weighting coefficient of the strongest space-frequency vector corresponding to the downlink channel based on the SCI and the first information, which have the same priority and are included in the UCI. Therefore, when UCI reporting resources are limited, the terminal device feeds back at least the SCI and the first information indicating the second frequency-domain DFT vector set, so as to improve the accuracy of the frequency-domain position corresponding to the SCI and determined by the network device based on the SCI and the first information, thereby ensuring the effectiveness of the precoding matrix as much as possible.

[0387] The following describes the manner of a specific data bearer of a UCI when the priority of the first information is the same as the priority of the SCI in the UCI sent by the terminal device in step S103 in embodiment 1.

[0388] Typically, the UCI sent by the terminal device in step S103 may include at least two parts, namely Part I and Part II.

[0389] Part I includes the quantity of non-zero weighting factors, RI, and CQI for all spatial layers.

[0390] In a possible implementation, Part II includes three groups, with different groups corresponding to different priorities.

[0391] For example, the three groups included in Part II may be represented as Group 0, Group 1, and Group 2. In addition, Group 0 has the highest priority, Group 1 has the second highest priority, and Group 2 has the lowest priority. Group 0 includes at least an SCI and a frequency domain DFT vector indicator (the first information described above in this embodiment).

[0392] Optionally, group 0 may further include a CSI-RS port indicator.

[0393] Optionally, Group 1 may be a first group determined based on relative amplitude (where relative amplitude indicates the relative amplitude of the strongest coefficient in another polarization direction with respect to the strongest coefficient indicated by the SCI) and priority.

[0394]

number

[0395] The amplitude of the weighting coefficient and the first

[0396]

number

[0397] The first one is determined based on the phase of the weighting coefficient and the priority.

[0398]

number

[0399] and a bitmap of weighting coefficients.

[0400] Optionally, Group 2 may be the last group to be assigned based on priority.

[0401]

number

[0402] The amplitude of the weighting coefficient and the final

[0403]

number

[0404] The final weighting factor is determined based on the phase and priority.

[0405]

number

[0406] and a bitmap of weighting factors.

[0407] In the example implementation, Group 0 includes a CSI-RS port indicator corresponding to each of one or more spatial layers, an SCI corresponding to each of one or more spatial layers, and a frequency-domain DFT vector indicator corresponding to each of one or more spatial layers.

[0408] Optionally, if there are multiple spatial layers and these multiple spatial layers correspond to the same CSI-RS port, Group 0 may include one CSI-RS port indicator, or Group 0 may include multiple CSI-RS port indicators, and the number of CSI-RS port indicators is equal to the number of spatial layers.

[0409] Optionally, if there are multiple spatial layers and these multiple spatial layers correspond to the same frequency-domain DFT vector indicator, group 0 may include one frequency-domain DFT vector indicator, or group 0 may include multiple frequency-domain DFT vector indicators, and the number of frequency-domain DFT vector indicators is equal to the number of spatial layers.

[0410] Group 1 is the first group determined based on the relative amplitude (relative amplitude indicates the relative amplitude of the strongest coefficient in another polarization direction with respect to the strongest coefficient indicated by the SCI) and priority.

[0411]

number

[0412] The amplitude of the weighting coefficient and the first

[0413]

number

[0414] The first one is determined based on the phase of the weighting coefficient and the priority.

[0415]

number

[0416] and a bitmap of weighting coefficients.

[0417] Group 2 is the last group to be prioritized.

[0418]

number

[0419] The amplitude of the weighting coefficient and the final

[0420]

number

[0421] The final weighting factor is determined based on the phase and priority.

[0422]

number

[0423] and a bitmap of weighting factors.

[0424] In a possible implementation, Part II includes two groups, with different groups corresponding to different priorities.

[0425] For example, the two groups included in Part II may be represented as Group 0 and Group 1. In addition, Group 0 has a high priority and Group 1 has a low priority. Group 0 includes at least an SCI and a frequency domain DFT vector indicator (the first information described above in this embodiment).

[0426] Optionally, group 0 further includes a CSI-RS port indicator.

[0427] Optionally, group 0 is a first group determined based on relative amplitude (relative amplitude indicates the relative amplitude of the strongest coefficient in another polarization direction with respect to the strongest coefficient indicated by SCI) and priority.

[0428]

number

[0429] The amplitude of the weighting coefficient and the first

[0430]

number

[0431] The first one is determined based on the phase of the weighting coefficient and the priority.

[0432]

number

[0433] and a bitmap of the weighting factors.

[0434] Optionally, Group 1 may be the last group to be prioritized.

[0435]

number

[0436] The amplitude of the weighting coefficient and the final

[0437]

number

[0438] The final weighting factor is determined based on the phase and priority.

[0439]

number

[0440] and a bitmap of weighting factors.

[0441] In the example implementation, Group 0 includes a CSI-RS port indicator corresponding to each of one or more spatial layers, an SCI corresponding to each of one or more spatial layers, a frequency-domain DFT vector indicator corresponding to each of one or more spatial layers, a relative amplitude (the relative amplitude indicates the relative amplitude of the strongest coefficient in another polarization direction with respect to the strongest coefficient indicated by the SCI), and a first order of priority.

[0442]

number

[0443] The amplitude of the weighting coefficient and the first

[0444]

number

[0445] The first one is determined based on the phase of the weighting coefficient and the priority.

[0446]

number

[0447] and a bitmap of weighting coefficients.

[0448] Optionally, if there are multiple spatial layers and these multiple spatial layers correspond to the same CSI-RS port, Group 0 may include one CSI-RS port indicator, or Group 0 may include multiple CSI-RS port indicators, and the number of CSI-RS port indicators is equal to the number of spatial layers.

[0449] Optionally, if there are multiple spatial layers and these multiple spatial layers correspond to the same frequency-domain DFT vector indicator, group 0 may include one frequency-domain DFT vector indicator, or group 0 may include multiple frequency-domain DFT vector indicators, and the number of frequency-domain DFT vector indicators is equal to the number of spatial layers.

[0450] Group 1 is the last group to be prioritized.

[0451]

number

[0452] The amplitude of the weighting coefficient and the final

[0453]

number

[0454] The final weighting factor is determined based on the phase and priority.

[0455]

number

[0456] and a bitmap of weighting factors.

[0457] In a possible implementation, the SCI in the UCI transmitted by the terminal device in step S103 is implemented in step S102 based on the implementation of embodiment 2. Specifically, in the UCI, the priority of the first information is lower than the priority of the SCI. The first information indicates a second frequency-domain DFT vector set selected by the terminal device, and the SCI indicates a space-frequency vector corresponding to the strongest coefficient of the second space-frequency vector set corresponding to the first frequency-domain DFT vector set configured by the network device and the CSI-RS port selected by the terminal device. In other words, the SCI indicates a space-frequency vector corresponding to the first frequency-domain DFT vector set configured by the network device and the strongest coefficient, and there is no correlation between the SCI and the second frequency-domain DFT vector set selected by the terminal device so that the network device can obtain the weighting coefficient of the strongest space-frequency vector corresponding to the downlink channel based on the high-priority SCI included in the UCI. Therefore, when the UCI reporting resource is limited, the terminal device feeds back at least the SCI, so that the accuracy of the frequency domain position corresponding to the SCI and determined by the network device based on the SCI can be improved to ensure the effectiveness of the precoding matrix as much as possible. In addition, when the UCI reporting resource is limited, the terminal device may not need to feed back the first information, so that the overhead can be reduced to a certain degree.

[0458] The following describes a specific data bearer scheme of the UCI when the priority of the first information is lower than the priority of the SCI in the UCI sent by the terminal device in step S103 in embodiment 2.

[0459] Typically, the UCI sent by the terminal device in step S103 may include at least two parts, namely Part I and Part II.

[0460] Part I includes the non-zero weighting factors, RI, and CQI for all spatial layers.

[0461] In a possible implementation, the first type of Part II includes three groups, with different groups corresponding to different priorities.

[0462] For example, the three groups included in Part II may be represented as Group 0, Group 1, and Group 2. Additionally, Group 0 has the highest priority, Group 1 has the second highest priority, and Group 2 has the lowest priority. Group 0 includes at least SCI.

[0463] Optionally, group 0 may further include a CSI-RS port indicator.

[0464] Optionally, Group 1 is a first group determined based on a frequency domain DFT vector indicator (the first information described above in this embodiment), a relative amplitude (the relative amplitude indicates the relative amplitude of the strongest coefficient in another polarization direction with respect to the strongest coefficient indicated by the SCI), and a priority.

[0465]

number

[0466] The amplitude of the weighting coefficient and the first

[0467]

number

[0468] The first one is determined based on the phase of the weighting coefficient and the priority.

[0469]

number

[0470] and a bitmap of weighting factors.

[0471] Optionally, Group 2 may be the last group to be assigned based on priority.

[0472]

number

[0473] The amplitude of the weighting coefficient and the final

[0474]

number

[0475] The final weighting factor is determined based on the phase and priority.

[0476]

number

[0477] and a bitmap of weighting factors.

[0478] A possible implementation would be Group 0 includes a CSI-RS port indicator corresponding to each of one or more spatial layers and an SCI corresponding to each of one or more spatial layers.

[0479] Optionally, if there are multiple spatial layers and these multiple spatial layers correspond to the same CSI-RS port, Group 0 may include one CSI-RS port indicator, or Group 0 may include multiple CSI-RS port indicators, and the number of CSI-RS port indicators is equal to the number of spatial layers.

[0480] Group 1 is a set of frequency domain DFT vector indicators, relative amplitudes (relative amplitudes indicate the relative amplitudes of the strongest coefficients in other polarization directions relative to the strongest coefficient indicated by the SCI), and the first set of priorities.

[0481]

number

[0482] The amplitude of the weighting coefficient and the first

[0483]

number

[0484] The first one is determined based on the phase of the weighting coefficient and the priority.

[0485]

number

[0486] and a bitmap of weighting coefficients.

[0487] Optionally, if there are multiple spatial layers and these multiple spatial layers correspond to the same frequency-domain DFT vector indicator, group 0 may include one frequency-domain DFT vector indicator, or group 0 may include multiple frequency-domain DFT vector indicators, and the number of frequency-domain DFT vector indicators is equal to the number of spatial layers.

[0488] Group 2 is the last group to be prioritized.

[0489]

number

[0490] The amplitude of the weighting coefficient and the final

[0491]

number

[0492] The final weighting factor is determined based on the phase and priority.

[0493]

number

[0494] and a bitmap of weighting factors.

[0495] While the present application has been described above in terms of a method, the present application will now be described in terms of an apparatus.

[0496] 6 is a schematic diagram of an implementation of a terminal device according to an embodiment of the present application. The terminal device may particularly implement the implementation process related to the terminal device in any one of the foregoing embodiments.

[0497] In an implementation, the terminal device 600 includes a transceiver unit 601 and a processing unit 602 .

[0498] The transceiver unit 601 is configured to receive first indication information, the first indication information indicating a first frequency-domain DFT vector set, a subset of the first frequency-domain DFT vector set including a second frequency-domain DFT vector set, and the second frequency-domain DFT vector set and a CSI-RS port selected by the terminal device correspond to the first spatial-frequency vector set.

[0499] The processing unit 602 is configured to determine a strongest coefficient indicator SCI based on the first indication information, where the SCI indicates a space-frequency vector corresponding to a strongest coefficient of a first space-frequency vector set, and the space-frequency vector set is correlated with a channel state information reference signal CSI-RS port.

[0500] The transceiver unit 601 is further configured to transmit uplink control information UCI, where the UCI includes first information and SCI, where the first information indicates a second frequency domain DFT vector set, and the first information and SCI have the same priority in the UCI.

[0501] Optionally, the first information and the SCI have the same priority in the UCI, in other words the priority of the first information in the UCI is the same as the priority of the SCI in the UCI.

[0502] In a possible implementation, the number of bits occupied by the SCI is correlated with the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors.

[0503] In a possible implementation, the number of bits occupied by the SCI is further correlated with the number of CSI-RS ports.

[0504] In a possible implementation, the number of bits occupied by the SCI satisfies a first scheme, which is:

[0505]

number

[0506] where 2L represents the number of CSI-RS ports and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors.

[0507] In a possible implementation, the number of bits occupied by the SCI satisfies a second scheme, which is:

[0508]

number

[0509] where 2L represents the number of CSI-RS ports and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors.

[0510] In a possible implementation, the number of bits occupied by the first information satisfies a third scheme, and the third scheme is as follows:

[0511]

number

[0512] where N represents the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors, and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors;

[0513]

number

[0514] represents the number of combinations of N to M items.

[0515] In a possible implementation, the number of bits occupied by the first information satisfies a fourth scheme, which is:

[0516]

number

[0517] where N represents the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors, and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors;

[0518]

number

[0519] represents the number of combinations between N-1 and M-1 items.

[0520] In a possible implementation, the terminal device 600 includes a transceiver unit 601 and a processing unit 602 .

[0521] The transceiver unit 601 is configured to receive first indication information, the first indication information indicating a first frequency-domain DFT vector set, a subset of the first frequency-domain DFT vector set including a second frequency-domain DFT vector set, 1 The frequency domain DFT vector set of and the CSI-RS port selected by the terminal device correspond to a second space-frequency vector set.

[0522] The processing unit 602 is configured to determine a strongest coefficient indicator SCI based on the first indication information, the SCI indicating a spatial frequency vector corresponding to a strongest coefficient of the second set of spatial frequency vectors.

[0523] The transceiver unit 601 is further configured to transmit uplink control information UCI, where the UCI includes first information and SCI, where the first information indicates a second frequency domain DFT vector set, and where a priority of the first information in the UCI is lower than a priority of the SCI in the UCI.

[0524] Optionally, the priority of the first information in the UCI is lower than the priority of the SCI in the UCI, in other words, the priority of the SCI in the UCI is higher than the priority of the first information in the UCI.

[0525] In a possible implementation, the number of bits occupied by the SCI is correlated with the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors.

[0526] In a possible implementation, the number of bits occupied by the SCI is further correlated with the number of CSI-RS ports.

[0527] In a possible implementation, the number of bits occupied by the SCI satisfies a fifth scheme, which is:

[0528]

number

[0529] where 2L represents the number of CSI-RS ports, N represents the quantity of frequency-domain DFT vectors in the first frequency-domain DFT vector set.

[0530] In a possible implementation, the number of bits occupied by the SCI satisfies a sixth scheme, which is:

[0531]

number

[0532] where 2L represents the number of CSI-RS ports and N represents the number of frequency-domain DFT vectors in the first frequency-domain DFT vector set.

[0533] In a possible implementation, the number of bits occupied by the first information satisfies a seventh scheme, which is:

[0534]

number

[0535] where N represents the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors, and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors;

[0536]

number

[0537] represents the number of combinations of N to M items.

[0538] In a possible implementation, the number of bits occupied by the first information satisfies an eighth scheme, and the eighth scheme is:

[0539]

number

[0540] where N represents the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors, and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors;

[0541]

number

[0542] represents the number of combinations between N-1 and M-1 items.

[0543] Please note that for details of the contents such as information execution processing of the unit of the terminal device 600, please refer to the description of the preceding method embodiment of the present application, and the details will not be described again in this specification.

[0544] 7 is a schematic diagram illustrating an implementation of a network device according to an embodiment of the present application, which may specifically implement the implementation process associated with the network device of any one of the foregoing embodiments.

[0545] In a possible implementation, the network device 700 includes a sending unit 701 and a receiving unit 702 .

[0546] The transmitting unit 701 is configured to transmit first indication information, the first indication information indicating a first frequency-domain DFT vector set, a subset of the first frequency-domain DFT vector set including a second frequency-domain DFT vector set, and the second frequency-domain DFT vector set and a CSI-RS port selected by the terminal device correspond to the first space-frequency vector set.

[0547] The receiving unit 702 is configured to receive uplink control information UCI, the UCI including first information and SCI, where the SCI indicates a space-frequency vector corresponding to a strongest coefficient of a first space-frequency vector set, the first information indicates a second frequency-domain DFT vector set, and the first information and the SCI have the same priority in the UCI.

[0548] Optionally, the first information and the SCI have the same priority in the UCI, in other words the priority of the first information in the UCI is the same as the priority of the SCI in the UCI.

[0549] In a possible implementation, the network device 700 includes a sending unit 701 and a receiving unit 702 .

[0550] The transmitting unit 701 is configured to transmit first indication information, the first indication information indicating a first frequency-domain DFT vector set, a subset of the first frequency-domain DFT vector set including a second frequency-domain DFT vector set, and the second frequency-domain DFT vector set and the CSI-RS port selected by the terminal device are related to a first frequency-domain DFT vector set. 1 corresponds to a set of spatial frequency vectors.

[0551] The receiving unit 702 is configured to receive uplink control information UCI, where the UCI includes first information and SCI, where the SCI indicates a space-frequency vector corresponding to a strongest coefficient of a second space-frequency vector set, the first information indicates a second frequency-domain DFT vector set, and a priority of the first information in the UCI is lower than a priority of the SCI in the UCI.

[0552] Optionally, the priority of the first information in the UCI is lower than the priority of the SCI in the UCI, in other words, the priority of the SCI in the UCI is higher than the priority of the first information in the UCI.

[0553] In a possible implementation, the number of bits occupied by the SCI is correlated with the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors.

[0554] In a possible implementation, the number of bits occupied by the SCI is further correlated with the number of CSI-RS ports.

[0555] In a possible implementation, the number of bits occupied by the SCI satisfies a fifth scheme, which is:

[0556]

number

[0557] where 2L represents the number of CSI-RS ports, N represents the quantity of frequency-domain DFT vectors in the first frequency-domain DFT vector set.

[0558] In a possible implementation, the number of bits occupied by the SCI satisfies a sixth scheme, which is:

[0559]

number

[0560] where 2L represents the number of CSI-RS ports and N represents the number of frequency-domain DFT vectors in the first frequency-domain DFT vector set.

[0561] In a possible implementation, the number of bits occupied by the first information satisfies a seventh scheme, which is:

[0562]

number

[0563] where N represents the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors, and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors;

[0564]

number

[0565] represents the number of combinations of N to M items.

[0566] In a possible implementation, the number of bits occupied by the first information satisfies an eighth scheme, and the eighth scheme is:

[0567]

number

[0568] where N represents the number of frequency-domain DFT vectors in the first set of frequency-domain DFT vectors, and M represents the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors;

[0569]

number

[0570] represents the number of combinations between N-1 and M-1 items.

[0571] Please note that for details of the contents such as information execution processing of the units of the network device 700, please refer to the description of the preceding method embodiment of the present application, and the details will not be described again in this specification.

[0572] 8 is a schematic diagram of a possible logical structure of a terminal device 800 related to the above-mentioned embodiment according to an embodiment of the present application. The terminal device 800 may include, but is not limited to, at least one processor 801 and a communication port 802. Furthermore, optionally, the apparatus may further include at least one of a memory 803 and a bus 804. In this embodiment of the present application, the at least one processor 801 is configured to perform control processing for the operation of the terminal device 800.

[0573] Additionally, the processor 801 may be a central processing unit, a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array, another programmable logic device, a transistor logic device, a hardware component, or any combination thereof. The processor may implement or execute various exemplary logic blocks, modules, and circuits described with reference to the contents disclosed in this application. Alternatively, the processor may be a combination that implements computing functions, such as a combination including one or more microprocessors, or a combination of a digital signal processor and a microprocessor. For convenience and conciseness, those skilled in the art may clearly understand that the specific work processes of the above-mentioned systems, devices, and units may refer to the corresponding processes in the above-mentioned method embodiments. Details will not be described again in this specification.

[0574] It should be noted that the terminal device 800 shown in Fig. 8 may be specifically configured to implement the steps implemented by the terminal device in the corresponding method embodiments described above and to implement the technical effects corresponding to the terminal device. For all specific implementations of the terminal device shown in Fig. 8, please refer to the description of the method embodiments described above. The details will not be described again in this specification.

[0575] 9 is a schematic diagram of the structure of the network device of the aforementioned embodiment according to an embodiment of the present application. For the structure of the network device, please refer to the structure shown in FIG.

[0576] The network device includes at least one processor 911 and at least one network interface 914. Optionally, the network device further includes at least one memory 912, at least one transceiver 913, and one or more antennas 915. The processor 911, the memory 912, the transceiver 913, and the network interface 914 are connected to each other, for example, via a bus. In this embodiment of the present application, the connection may include various interfaces, transmission lines, buses, etc. This is not limited in this embodiment. The antenna 915 is connected to the transceiver 913. The network interface 914 is configured to enable the network device to communicate with another communication device via a communication link. For example, the network interface 914 may include a network interface between the network device and a core network device, such as an S1 interface. The network interface may include a network interface between the network device and another network device (e.g., another network device or a core network device), such as an X2 or Xn interface.

[0577] The processor 911 is mainly configured to process communication protocols and communication data, to control the entire network device, to execute software programs, and to process data of the software programs, for example, to support the network device in performing the operations described in the embodiments. The network device may include a baseband processor and a central processing unit. The baseband processor is mainly configured to process communication protocols and communication data. The central processing unit is mainly configured to: network The processor 911 in FIG. 9 may integrate the functions of a baseband processor and a central processing unit. It will be understood by those skilled in the art that the baseband processor and the central processing unit may alternatively be processors independent of each other and interconnected using a technology such as a bus. network The device may include multiple baseband processors to accommodate different network standards; network The device is network The device may contain multiple central processing units to increase its processing power; network It may be understood that the components of the device may be connected via various buses. The baseband processor may also be expressed as a baseband processing circuit or a baseband processing chip. The central processing unit may also be expressed as a central processing circuit or a central processing chip. The functions for processing communication protocols and communication data may be built into the processor or may be stored in memory in the form of a software program. The processor executes the software program to implement the baseband processing functions.

[0578] The memory is mainly configured to store software programs and data. The memory 912 may exist independently and be connected to the processor 911. Optionally, the memory 912 may be integrated together with the processor 911, for example, in one chip. The memory 912 may store program codes for executing the technical solutions of the embodiments of the present application, and the processor 911 controls the execution thereof. Various types of computer program codes that are executed may also be considered as drivers for the processor 911.

[0579] Figure 9 shows only one memory and one processor. network The device may have multiple processors and multiple memories. The memory may also be referred to as a storage medium, a storage device, etc. The memory may be a storage element located on the same chip as the processor, i.e., an on-chip storage element, or may be an independent storage element. This is not a limitation in the embodiments of the present application.

[0580] The transceiver 913 may be configured to support receiving or transmitting high-frequency signals between the network device and the terminal. The transceiver 913 may be connected to an antenna 915. The transceiver 913 includes a transmitter Tx and a receiver Rx. Specifically, the one or more antennas 915 may receive high-frequency signals. The receiver Rx of the transceiver 913 is configured to receive the high-frequency signals from the antenna, convert the high-frequency signals into digital baseband signals or digital intermediate frequency signals, and provide the digital baseband signals or digital intermediate frequency signals to the processor 911 so that the processor 911 performs further processing, such as demodulation and decoding, on the digital baseband signals or digital intermediate frequency signals. In addition, the transmitter Tx of the transceiver 913 is further configured to receive modulated digital baseband signals or modulated digital intermediate frequency signals from the processor 911, convert the modulated digital baseband signals or modulated digital intermediate frequency signals into high-frequency signals, and transmit the high-frequency signals via the one or more antennas 915. Specifically, the receiver Rx may selectively perform one-level or multi-level downmixing and analog-to-digital conversion on the high-frequency signal to obtain a digital baseband signal or a digital intermediate frequency signal. The order of the downmixing and analog-to-digital conversion processes is adjustable. The transmitter Tx may selectively perform one-level or multi-level upmixing and digital-to-analog conversion on the modulated digital baseband signal or the modulated digital intermediate frequency signal to obtain a high-frequency signal. The order of the upmixing and digital-to-analog conversion processes is adjustable. The digital baseband signal and the digital intermediate frequency signal may be collectively referred to as a digital signal.

[0581] A transceiver may also be referred to as a transceiver unit, a transceiver device, etc. Optionally, components for implementing a receiving function in a transceiver unit may be considered as a receiving unit, and components for implementing a transmitting function in a transceiver unit may be considered as a transmitting unit, in other words, a transceiver unit includes a receiving unit and a transmitting unit. A receiving unit may also be referred to as a receiver, an input port, a receiving circuit, etc. A transmitting unit may also be referred to as a transmitter, a transmitting circuit, etc.

[0582] It should be noted that the network device shown in Figure 9 may be specifically configured to implement the steps implemented by the network device in the above-described method embodiments and to implement the technical effects corresponding to the network device. For all specific implementations of the network device shown in Figure 9, please refer to the description of the above-described method embodiments. Details will not be described again herein.

[0583] An embodiment of the present application further provides a computer-readable storage medium storing one or more computer-executable instructions, which, when executed by a processor, cause the processor to perform a method according to a possible implementation of the terminal device of the aforementioned embodiment.

[0584] An embodiment of the present application further provides a computer-readable storage medium storing one or more computer-executable instructions that, when executed by a processor, cause the processor to perform a method according to a possible implementation of the network device of the aforementioned embodiment.

[0585]

[0013] An embodiment of the present application further provides a computer program product (also referred to as a computer program) storing one or more computer-executable instructions, which, when executed by a processor, causes the processor to implement the method in the above possible implementation of the terminal device.

[0586] An embodiment of the present application further provides a computer program product storing one or more computer-executable instructions, which, when executed by a processor, cause the processor to perform the method in the above possible implementation of the network device.

[0587] An embodiment of the present application further provides a chip system. The chip system includes at least one processor configured to support the terminal device in implementing functions in the above-mentioned possible implementations of the terminal device. Optionally, the chip system further includes an interface circuit. The interface circuit provides program instructions and / or data to the at least one processor. In a possible design, the chip system may further include a memory. The memory is configured to store program instructions and data required for the terminal device. The chip system may include a chip, or may include a chip and another individual component.

[0588] An embodiment of the present application further provides a chip system. The chip system includes at least one processor configured to support the network device in implementing functions in the above-mentioned possible implementation of the network device. Optionally, the chip system further includes an interface circuit. The interface circuit provides program instructions and / or data to the at least one processor. In a possible design, the chip system may further include a memory. The memory is configured to store program instructions and data required for the network device. The chip system may include a chip, or may include a chip and another individual component. The network device may specifically be the network device in the above-mentioned method embodiment.

[0589] An embodiment of the present application further provides a communication system, the architecture of which includes the terminal device and the network device of any one of the preceding embodiments.

[0590] In some embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the described device embodiments are merely examples. For example, the division into units is merely a logical division of function, and other divisions may be used in actual implementation. For example, multiple units or components may be combined or integrated to form another system, or some features may be omitted or not implemented. In addition, the shown or discussed mutual couplings or direct couplings or communication connections may be implemented via some interfaces. Indirect couplings or communication connections between devices or units may be implemented in electronic, mechanical, or other forms.

[0591] The units described as separate parts may or may not be physically separated, and the parts presented as units may or may not be physical units, specifically located in one location or distributed across multiple network units. Some or all of the units may be selected based on actual requirements to achieve the objectives of the solutions of the embodiments.

[0592] In addition, the functional units in the embodiments of the present application may be integrated into one processing unit, each unit may exist physically alone, or two or more units may be integrated into one unit. The integrated unit may be implemented in the form of hardware or in the form of a software functional unit. When the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, the integrated unit may be stored in a computer-readable storage medium. Based on such understanding, the essential technical solution of the present application, the portion contributing to the prior art, or all or part of the technical solution may be implemented in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for instructing a computer device (which may be a personal computer, a server, a network device, etc.) to perform all or part of the steps of the method described in the embodiments of the present application. The storage medium includes any medium capable of storing program code, such as a USB flash drive, a removable hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0593] The above description is merely a specific implementation of the embodiments of the present application, and the protection scope of the embodiments of the present application is not limited thereto. Any modifications or replacements that can be easily conceived by those skilled in the art within the technical scope disclosed in the embodiments of the present application shall fall within the protection scope of the embodiments of the present application. Therefore, the protection scope of the embodiments of the present application shall be determined by the protection scope of the claims.

Claims

1. A channel information feedback method, comprising: Receiving first indication information by a terminal device or a chip of the terminal device (S101), wherein the first indication information indicates a first frequency-domain Discrete Fourier Transform (DFT) vector set, the first frequency-domain DFT vector set includes a second frequency-domain DFT vector set, and the second frequency-domain DFT vector set and a Channel State Information Reference Signal (CSI-RS) port selected by the terminal device or the chip of the terminal device correspond to a first space-frequency vector set; Determining a strongest coefficient indicator (SCI) and first information based on the first indication information by the terminal device or a chip of the terminal device (S102), wherein the SCI indicates a space-frequency vector corresponding to a strongest coefficient of the first space-frequency vector set, and the first information indicates the second frequency-domain DFT vector set; Sending uplink control information (UCI) by the terminal device or a chip of the terminal device (S103), wherein the UCI includes the first information and the SCI, and the first information and the SCI have the same priority in the UCI; A channel information feedback method including:

2. The terminal device or the chip of the terminal device determines (S102) a strongest coefficient indicator (SCI) and first information based on the first indication information, The terminal device or a chip of the terminal device determines the SCI, the first information, and a group 1 based on the first indication information (S102), and the group 1 is a first group determined based on a priority order. [Equation 1] a bitmap of weighting coefficients, where ν denotes the number of layers, 2L denotes the number of the selected CSI-RS ports, M denotes the number of frequency-domain DFT vectors in the second frequency-domain DFT vector set, and K NZ 2. The method of claim 1, wherein: ≠ ≠ indicates a quantity of non-zero weighting factors; and the priority of the first information and the priority of the SCI are higher than the priority of the group 1.

3. A channel information feedback method, comprising: Sending first indication information (S101) by a network device or a chip of the network device, the first indication information indicating a first frequency-domain Discrete Fourier Transform (DFT) vector set, the first frequency-domain DFT vector set including a second frequency-domain DFT vector set, and the second frequency-domain DFT vector set and a channel state information reference signal (CSI-RS) port selected by a terminal device or a chip of the terminal device correspond to a first space-frequency vector set; receiving uplink control information (UCI) by the network device or a chip of the network device (S103), wherein the UCI includes first information and a strongest coefficient indicator (SCI), the SCI indicating a space-frequency vector corresponding to a strongest coefficient of the first space-frequency vector set, the first information indicating the second frequency-domain DFT vector set, and the first information and the SCI having the same priority in the UCI; A channel information feedback method including:

4. The priority of the first information and the priority of the SCI are higher than the priority of Group 1, and Group 1 is a first information group determined based on the priority. [Equation 2] a bitmap of weighting coefficients, where ν denotes the number of layers, 2L denotes the number of the selected CSI-RS ports, M denotes the number of frequency-domain DFT vectors in the second frequency-domain DFT vector set, and K NZ The method of claim 3 , wherein ∇ denotes the number of non-zero weighting coefficients.

5. The method of claim 2 or 4, wherein the UCI further includes the Group 1.

6. 5. The method of claim 1, wherein the quantity of bits occupied by the SCI is correlated with the quantity of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors.

7. The method of claim 6 , wherein the quantity of bits occupied by the SCI is further correlated with the quantity of CSI-RS ports.

8. The number of bits occupied by the SCI satisfies a first scheme, and the first scheme comprises: [Equation 3] where 2L represents the number of CSI-RS ports and M represents the number of frequency-domain DFT vectors in the second frequency-domain DFT vector set; [Equation 4] is log 2 8. The method of claim 7, wherein (2L) represents rounding up.

9. The number of bits occupied by the SCI satisfies a second scheme, the second scheme comprising: [Equation 5] where 2L represents the number of CSI-RS ports and M represents the number of frequency-domain DFT vectors in the second frequency-domain DFT vector set; [Equation 6] is log 2 (2L) represents rounding up, [Equation 7] is log 2 8. The method of claim 7, wherein (M) represents rounding up.

10. The number of bits occupied by the first information satisfies a third scheme, and the third scheme is: [Equation 8] wherein N represents the number of frequency domain DFT vectors in the first frequency domain DFT vector set, and M represents the number of frequency domain DFT vectors in the second frequency domain DFT vector set; [Equation 9] teeth, [Equation 10] represents rounding up, [0011] The method according to claim 1 , wherein M represents the number of combinations of N to M.

11. The number of bits occupied by the first information satisfies a fourth scheme, and the fourth scheme is: [0012] wherein N represents the number of frequency domain DFT vectors in the first frequency domain DFT vector set, and M represents the number of frequency domain DFT vectors in the second frequency domain DFT vector set; [0013] teeth, [0014] represents rounding up, [Equation 15] The method according to any one of claims 1 to 4, wherein represents the number of combinations of N-1 to M-1 items.

12. A communication device (600) comprising a transceiver unit (601) and a processing unit (602), the transceiver unit (601) is configured to receive first indication information, the first indication information indicating a first frequency-domain Discrete Fourier Transform (DFT) vector set, a subset of the first frequency-domain DFT vector set including a second frequency-domain DFT vector set, the second frequency-domain DFT vector set and a Channel State Information Reference Signal (CSI-RS) port selected by the communication device correspond to the first space-frequency vector set; The processing unit (602) is configured to determine a strongest coefficient indicator (SCI) and first information based on the first indication information, wherein the SCI indicates a spatial-frequency vector corresponding to a strongest coefficient of the first spatial-frequency vector set, and the first information indicates the second frequency-domain DFT vector set; The transceiver unit (601) is further configured to transmit uplink control information (UCI), the UCI including the first information and the SCI, and the first information and the SCI having the same priority in the UCI.

13. The processing unit (602) is configured to determine a strongest coefficient indicator (SCI) and first information based on the first indication information, The processing unit (602) is configured to determine the SCI, the first information, and Group 1 based on the first indication information, and the Group 1 is a first group determined based on a priority. [0016] a bitmap of weighting coefficients, where ν denotes the number of layers, 2L denotes the number of the selected CSI-RS ports, M denotes the number of frequency-domain DFT vectors in the second frequency-domain DFT vector set, and K NZ 13. The apparatus (600) of claim 12, comprising: wherein: ≠ ≠ ≠ indicates a quantity of non-zero weighting factors; and the priority of the first information and the priority of the SCI are higher than the priority of the group 1.

14. A communication device (700) including a transmitting unit and a receiving unit, The transmitting unit (701) is configured to transmit first indication information, the first indication information indicating a first frequency-domain Discrete Fourier Transform (DFT) vector set, a subset of the first frequency-domain DFT vector set including a second frequency-domain DFT vector set, and the second frequency-domain DFT vector set and a Channel State Information Reference Signal (CSI-RS) port selected by a terminal device or a chip of the terminal device correspond to the first space-frequency vector set; 1. A communications device, comprising: a receiving unit (702) configured to receive uplink control information (UCI), the UCI including first information and a strongest coefficient indicator (SCI), the SCI indicating a space-frequency vector corresponding to a strongest coefficient of the first space-frequency vector set; the first information indicating the second frequency-domain DFT vector set; and the first information and the SCI having the same priority in the UCI.

15. The priority of the first information and the priority of the SCI are higher than the priority of Group 1, and Group 1 is a first information group determined based on the priority. [Equation 17] a bitmap of weighting coefficients, where ν denotes the number of layers, 2L denotes the number of the selected CSI-RS ports, M denotes the number of frequency-domain DFT vectors in the second frequency-domain DFT vector set, and K NZ 15. The apparatus (700) of claim 14, wherein ∇ denotes the number of non-zero weighting coefficients.

16. 16. The apparatus (600, 700) of claim 13 or 15, wherein the UCI further comprises the group 1.

17. 16. The apparatus (600, 700) of any one of claims 12 to 15, wherein the quantity of bits occupied by the SCI is correlated with the number of frequency-domain DFT vectors in the second set of frequency-domain DFT vectors.

18. 18. The apparatus (600, 700) of claim 17, wherein the number of bits occupied by the SCI is further correlated with a number of CSI-RS ports.

19. The number of bits occupied by the SCI satisfies a first scheme, and the first scheme comprises: [Equation 18] where 2L represents the number of CSI-RS ports and M represents the number of frequency-domain DFT vectors in the second frequency-domain DFT vector set; [Equation 19] is log 2 20. The apparatus (600, 700) of claim 18, representing rounding up (2L).

20. The number of bits occupied by the SCI satisfies a second scheme, the second scheme comprising: [Equation 20] where 2L represents the number of CSI-RS ports and M represents the number of frequency-domain DFT vectors in the second frequency-domain DFT vector set; [0000] is log 2 (2L) represents rounding up, [Equation 22] is log 2 20. The apparatus (600, 700) of claim 18, wherein (M) represents rounding up.

21. The number of bits occupied by the first information satisfies a third scheme, and the third scheme is: [Equation 23] wherein N represents the number of frequency domain DFT vectors in the first frequency domain DFT vector set, and M represents the number of frequency domain DFT vectors in the second frequency domain DFT vector set; [0000] teeth, [Equation 25] represents rounding up, [Equation 26] 16. The apparatus according to claim 12, wherein M represents the number of combinations of N to M.

22. The number of bits occupied by the first information satisfies a fourth scheme, and the fourth scheme is: [Equation 27] wherein N represents the number of frequency domain DFT vectors in the first frequency domain DFT vector set, and M represents the number of frequency domain DFT vectors in the second frequency domain DFT vector set; [0000] teeth, [0000] represents rounding up, [Equation 30] The apparatus according to any one of claims 12 to 15, wherein represents the number of combinations between N-1 and M-1.

23. 1. A communications device comprising at least one processor coupled to a memory, the memory is configured to store programs or instructions; An apparatus, wherein said at least one processor is configured to execute said program or said instructions, enabling said apparatus to perform the method of claim 1 or 3.

24. A computer program comprising program instructions, said program instructions being program instructions for causing a computer to carry out the method according to claim 1 or 3.

25. A computer readable storage medium, the computer readable storage medium storing program instructions, the program instructions being program instructions for causing a computer to perform the method of claim 1 or 3.

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