Abstract: A basis feedback method and an apparatus are provided to implement an effective solution of feeding back a weighting coefficient matrix in a non-DFT basis. In this application, when a spatial domain eigenbasis and a frequency domain eigenbasis (or a space-frequency eigenbasis) are reported, the spatial domain eigenbasis and the frequency domain eigenbasis are decomposed based on a spatial domain basis and a frequency domain basis (or the space-frequency eigenbasis is decomposed based on a space-frequency basis); the spatial domain eigenbasis and the frequency domain eigenbasis (or the space-frequency eigenbasis) are respectively indicated by reporting weighting coefficients obtained through decomposition; and a reporting priority of the weighting coefficient is associated with a sequence number of a spatial domain basis, a sequence number of a frequency domain basis, a sequence number of a spatial domain eigenbasis, and a sequence number of a frequency domain eigenbasis.

Abstract: This application provides a communication method and a communication apparatus. The communication method includes: A terminal device reports a full-channel measurement result to a network device through two-stage feedback. The terminal device feeds back, at a first stage, at least one space-frequency basis group in which all antenna ports of the terminal device have a non-zero coefficient in a matrix corresponding to a space domain basis set and a frequency domain basis set, and specifically feeds back, at a second stage, a location at which each of all the antenna ports has a non-zero coefficient in the at least one space-frequency basis group. In embodiments of this application, resource overheads for full-channel feedback can be reduced in the two-stage feedback method.

Abstract: A channel state information feedback method and a related product are provided. A network device sends first indication information. A terminal device sends second indication information based on the first indication information. The second indication information indicates X groups of basis vectors. The first indication information indicates P groups of basis vectors. The X groups of basis vectors belong to the P groups of basis vectors. Only a basis vector for representing a sub-eigenspace beam needs to be selected from a limited quantity of basis vector groups. In this way, indication overheads of a basis vector for representing a sub-eigenspace beam are reduced, and processing complexity is reduced.

Abstract: The present disclosure relates to phase compensation methods and communication apparatuses. In one example method, a terminal receives at least two reference signal sets, where each of the at least two reference signal sets includes at least one reference signal. The terminal sends first information based on the at least two reference signal sets, where the first information indicates a corresponding phase variation between reference signal sets in the at least two reference signal sets at a first moment.

Abstract: A channel state information reporting method and a related apparatus is described. The method includes: receiving a first channel state information reference signal CSI-RS; sending, to a network device, first channel state information CSI obtained based on a measurement result of the first CSI-RS. The first CSI includes indication information of a first vector set for the network device to determine a target precoding matrix. The method further includes receiving a second CSI-RS; and sending, to the network device, second CSI obtained based on a measurement result of the second CSI-RS and a second vector set.

Abstract: In accordance with an embodiment, a method includes obtaining Mv frequency domain components, where the Mv frequency domain components are a subset of N candidate frequency domain components, and Mv is a positive integer; and sending first indication information, where the first indication information indicates the Mv frequency domain components, the first indication information occupies ? log 2 ? ( N - 1 M v - 1 ) ? bits, and N is a positive integer greater than Mv.

Abstract: This application provides a resource configuration method. The method includes: A terminal device receives a channel state information CSI reporting configuration from a network device, where the CSI reporting configuration includes N fields, the N fields are in one-to-one correspondence with N CSI resource configurations, a first field in the N fields indicates a first carrier associated with a first CSI resource configuration that is in the N CSI resource configurations and that corresponds to the first field, the N CSI resource configurations are associated with N carriers, and N is a positive integer greater than 1; the terminal device obtains CSI based on the CSI reporting configuration; and the terminal device sends the CSI to the network device.

Abstract: This application provides a channel measurement method and a communication apparatus, to improve accuracy of a channel measurement result, and may be applied to a communication system. The method includes: A terminal device receives first information indicating a channel state information reference signal CSI-RS resource occupied by a CSI-RS, receives the CSI-RS on the CSI-RS resource, and sends channel state information CSI.

Abstract: A pilot mapping method and an apparatus are provided, to implement pilot mapping corresponding to ports whose quantity is greater than 32. The method includes: determining time-frequency resource positions of CDM groups that correspond to each group of ports in X groups of ports and that are associated with Y positions, where each group of ports is distributed in a different resource block RB, X is determined based on a total quantity P of ports, a quantity of CDM groups is determined based on P and a type of the CDM group, X>1, Y?1, P>32, and X, Y, and P are integers; and sending first indication information, where the first indication information indicates the time-frequency resource positions of the CDM groups that correspond to each group of ports in the X groups of ports and that are associated with the Y positions.

Abstract: In accordance with an embodiment, a method includes transmitting first indication information to a terminal device, where the first indication information indicates a first parameter combination including at least two of the following: a first value of Mv, a first value of ?, and a first value of ?. The first parameter combination is for determining that a first coefficient matrix to be indicated by the terminal device includes a maximum of K0 non-zero elements, and K0 is determined based on the first values of Mv, ?, and ?. The terminal device sends a second information indication to the network device, where the second indication information indicates K2 non-zero elements in the first coefficient matrix, and K2 is less than or equal to K0.

Abstract: This application provides a capability reporting method and an apparatus, to improve effectiveness of CSI report reporting, and may be applied to a communication system. The method includes: A terminal device generates first information. The first information includes at least one piece of capability information of the terminal device, and the capability information indicates a quantity of time domain units supported by the terminal device for a precoding matrix indicator (PMI). The terminal device sends the first information to a network device.

Abstract: The present disclosure provides a method for determining channel state information and an apparatus, relating to the field of communication technologies, to improve accuracy of channel state information (CSI) fed back by a terminal. In the method, a terminal may determine, based on a plurality of reference signals on a plurality of reference signal resources and a plurality of power offsets, a precoding matrix that matches a channel for actual transmission, so that a channel quality indicator (CQI) obtained based on the precoding matrix conforms to channel quality of the channel for actual transmission. In other words, in this case, the terminal can obtain an accurate CQI, thereby improving accuracy of CSI fed back by the terminal to a network device, and improving transmission performance.

Abstract: Embodiments of this application provides a method and an apparatus for channel measurement. A network device sends first information, where the first information indicates K sending moments for sending an NZP CSI-RS and a sending gap m between adjacent sending moments in the K sending moments. After receiving the first information, a terminal device may determine a time domain location of a target CSI reference resource, and receive a measurement signal before the target CSI reference resource (time domain location). The terminal device reports, based on the measurement signal, CSI to the network device at a time domain location of CSI report, and the network device receives the reported CSI. According to the method in embodiments of this application, channel measurement and determining of channel information can be effectively completed, to ensure communication performance of the terminal device.

Abstract: In accordance with an embodiment, a method includes receiving first indication information from a network device, where the first indication information indicates a first parameter combination including at least two of the following: a first value of Mv, a first value of ?, and a first value of ?. The first parameter combination is configured to be used to determine a a maximum of K0 non-zero elements for a first coefficient matrix, and K0 is determined based on the first values of Mv, ?, and ?; sending a second information indication to the network device, where the second indication information indicates K2 non-zero elements in the first coefficient matrix, and K2 is less than or equal to K0.

Abstract: This application provides a method for determining a channel state information measurement parameter and a related apparatus. The method includes: A terminal device receives, from a network device, first information indicating a quantity NTRP of reference signal resources used for channel state information (channel state information, CSI) measurement, where a CSI reporting type is aperiodic CSI reporting, and NTRP is a positive integer greater than or equal to 1. The terminal device determines a time domain position of a CSI reference resource based on the first information. The technical solutions provided in this application can increase a success rate of reporting CSI by the terminal device.

Abstract: Embodiments of this application provide a communication method and apparatus. A DMRS type is a type 1, and a quantity of DMRS ports in a DMRS port set is greater than 4, that is, a quantity of DMRS ports supported on a single symbol is greater than 4. Alternatively, a DMRS type is a type 2, and a quantity of DMRS ports in a DMRS port set is greater than 6, that is, a quantity of DMRS ports supported on a single symbol is greater than 6. In this way, the frequency domain position occupied by the PTRS port is determined when the quantity of DMRS ports supported on the single symbol increases.

Abstract: This application discloses a communication method and a communication apparatus. In the method, A communication apparatus determines first information, where the first information indicates a precoding matrix, and the first information includes a plurality of coefficients Cl,i,f,d, where l is a transport layer sequence number, i is a channel state information reference signal (CSI-RS) port sequence number or a spatial domain basis sequence number, f is a frequency domain basis sequence number, d is a Doppler domain basis sequence number, the coefficient Cl,i,f,d corresponds to a priority indication Pri(l, i, f, d), and the coefficients Cl,i,f,d in the first information are arranged based on Pri(l, i, f, d). The communication apparatus sends the first information to a network device.

Abstract: A method applied to a communication apparatus includes receiving first information and second information from a network device, wherein the first information indicates reference signal port indexes corresponding to m code division multiplexing groups, m is a positive integer greater than or equal to 2, at least two of the m code division multiplexing groups support different quantities of orthogonal ports, and the second information indicates a first reference signal port index in a reference signal port correspondence indicated by the reference signal port indexes corresponding to the m code division multiplexing groups. Based on the first reference signal port index, a port used for a reference signal is determined.

Abstract: Example reference signal port indication methods and apparatus are described. In one example method, a network device generates first information and second information, and sends the first information and the second information to a terminal device. The first information indicates one or more reference port indices. The second information indicates a manner of determining one or more target port indices based on the one or more reference port indices indicated by the first information. The one or more target port indices indicate one or more ports used for a reference signal. The one or more ports used for the reference signal are indicated by the first information and the second information.

Abstract: This application relates to the field of communication technologies, and provides an information transmission method and an apparatus. In this method, a radio access network device sends, to a terminal device, first indication information indicating first information and second information and second indication information indicating a first quantity of DFT vectors, the first information indicates a first quantity of to-be-selected ports, and the second information indicates a first compression factor. The radio access network device further sends a reference signal to the terminal device. The terminal device sends downlink channel state information to the radio access network device based on the first indication information, the second indication information, and the reference signal. The compression factor is a compression factor of a complex coefficient matrix. There is a correspondence between the compression factor and a quantity of transport layers.