Abstract: One example method includes receiving one or more precoded reference signals, where the one or more precoded reference signals are obtained by precoding one or more reference signals based on K angle vectors. First indication information can then be generated, where the first indication information is used to indicate at least one delay vector and P weighting coefficients corresponding to P angle-delay pairs, the at least one delay vector and the P weighting coefficients are determined based on the one or more precoded reference signals, each of the P angle-delay pair includes one of the K angle vectors and one of the at least one delay vector, and the P angle-delay pairs and the P weighting coefficients are used to determine a precoding matrix, where P and K are positive integers, and where P?1, K?1. The first indication information can then be sent.

Abstract: This application provides a method for configuring channel state information CSI reporting and a communication apparatus. The method includes: A terminal device receives configuration information for CSI reporting, where the configuration information for the CSI reporting is associated with configuration information of a first reference signal and configuration information of a second reference signal, the second reference signal is used for measuring an uplink channel, and the first reference signal is used for measuring a downlink channel. The terminal device performs channel measurement based on the first reference signal and the second reference signal to generate a CSI, and feeds back CSI. By using uplink and downlink channel reciprocity, the terminal device may not need to feed back information with reciprocity, for example, an angle and a delay, so that feedback overheads of the terminal device are reduced.

Abstract: Embodiments of this application disclose a channel estimation method and apparatus, and relate to the field of communications technologies, to help reduce indication overheads. The method may include: generating and sending indication information, where the indication information is used to indicate M N-dimensional precoding vectors, each precoding vector is applied to one of M frequency bands, the M N-dimensional precoding vectors form a space-frequency matrix, and the space-frequency matrix is generated by performing weighted combination on a plurality of space-frequency component matrices, where the space-frequency matrix is an M×N-dimensional space-frequency vector or an X×Y space-frequency matrix, X and Y are one and the other of M and N, M?1, N?2, and both M and N are integers.

Abstract: This application discloses a channel estimation method and apparatus, and relates to the field of communications technologies, to help reduce indication overheads. The method may include: generating and sending indication information. The indication information indicates K N-dimensional spatial-domain component vectors, L M-dimensional frequency-domain component vectors, and a weight matrix, for constructing an M×N-dimensional spatial-frequency matrix, or an M×N or N×M spatial-frequency matrix.

Abstract: Embodiments of this application disclose channel state information feedback and receiving methods, a transmit-end device and a receive-end device, and relate to the field of communications technologies. The method includes: generating and sending, by a transmit-end device, codebook indication information of K transport layers, where K is an integer greater than or equal to 2; the codebook indication information includes: L pieces of beam information used by the K transport layers, and indication information used to indicate beam information associated with each of the K transport layers; L is an integer greater than or equal to 2, and a quantity of pieces of beam information associated with at least one of the K transport layers is less than L. Implementing a channel state information feedback and receiving technology provided in this application helps reduce feedback overheads of channel state information.

Abstract: Example precoding vector indication methods, precoding vector determining methods, and communications apparatus to reduce feedback overheads are described. One example method includes generating and sending a channel state information (CSI) report by a terminal device. A network device determines a precoding vector of one or more frequency domain units based on the CSI report. The CSI report is used to indicate M space-frequency units and a weighting coefficient of a part or all of the M space-frequency units, each of the M space-frequency units corresponds to one beam vector and one frequency domain vector, and a weighted sum of the part or all of the M space-frequency units is used to determine the precoding vector of the one or more frequency domain units.

Abstract: A synchronization processing method, including sending, in a first time unit, by a network device, a first synchronization signal having one or more first beams to a terminal device, and sending, in a second time unit, a second synchronization signal having one or more second beams to the terminal device. The first synchronization signal and the second synchronization signal cause the terminal device to determine, according to the first synchronization signal and the second synchronization signal, an optimal transmit beam of the network device for the terminal device from the one or more first beam and the one or more second beams, and further to determine a time sequence in which the optimal transmit beam is located. A time offset corresponding to each first beam and second beams is different, and is a difference between a time sequence of the beams and a time sequence of the second beams.

Abstract: This application relates to channel state information (CSI) feedback methods and devices. One method comprises: receiving, by a terminal device from a network device, indication information of a channel state information (CSI) reporting band; determining, by the terminal device, based on the indication information, a subset of subbands in a bandwidth part configured for the terminal device for CSI reporting; determining, by the terminal device. CSI reporting priorities of the subset of the subbands based on index numbers of the subset of the subbands, wherein the index numbers of the subset of the subbands are numbered in an ascending numerical order; and sending, by the terminal device to the network device, CSI of M subbands with higher CSI reporting priorities in the subset of the subbands compared to a remainder of subbands in the subset of subbands.

Abstract: This disclosure discloses methods and apparatuses for signal processing. In an implementation, a method comprises: generating first indication information, wherein the first indication information indicates L1 space domain vectors in a space domain vector set, K1 frequency domain vectors in a frequency domain vector set, and T1 space-frequency component matrices, wherein a precoding vector of one or more frequency domain units is determined by a weighted sum of the T1 space-frequency component matrices, wherein the L1 space domain vectors and the K1 frequency domain vectors correspond to M1 space-frequency component matrices that comprise the T1 space-frequency component matrices, wherein each of the M1 space-frequency component matrices is uniquely determined by a different combination of one of the L1 space domain vectors and one of the K1 frequency domain vectors; and sending the first indication information.

Abstract: Embodiments of the present invention provide a precoding vector indicating method, a precoding vector determining method, a receive end device, and a transmit end device. The precoding vector indicating method includes: determining a plurality of component vectors of an ideal precoding vector and a weight of each component vector based on at least one basic codebook, where each component vector is a column vector of one of the at least one basic codebook; and sending a precoding vector indicator, where the precoding vector indicator is used to indicate the plurality of component vectors and the weight of each component vector. The embodiments of the present invention further provide a precoding vector determining method, a receive end device, and a transmit end device. In the technical solutions provided in the embodiments of the present invention, a basic codebook is constructed based on a plurality of parameters, so that the basic codebook can be used to more accurately describe a channel environment.

Abstract: This application provides methods and apparatuses for precoding vector indication and determination. One method includes: generating, by a first communications device, first indication information that indicates one or more port selection vectors, one or more frequency domain vectors, and one or more linear combination coefficients, wherein each of the one or more linear combination coefficients corresponds to a port selection vector and a frequency domain vector, each of the one or more port selection vectors indicates a port of a precoded reference signal, and each of the one or more frequency domain vectors indicates a variation pattern of a channel in a frequency domain; and sending the first indication information to a second communications device.

Abstract: Embodiments of this application disclose a channel estimation method and apparatus, and relate to the field of communications technologies. The method may include: generating and sending indication information, where the indication information is used to indicate L space-frequency basis vectors for constructing an M×N-dimensional space-frequency vector; the space-frequency vector includes M N-dimensional precoding vectors, each precoding vector is used in one of M frequency bands, and the space-frequency vector is generated by performing a weighted combination on L space-frequency component vectors; each of the L space-frequency component vectors is a vector including M×N elements that are in one of the L space-frequency basis vectors, and each of the L space-frequency basis vectors is an Nf×N-dimensional vector; the space-frequency basis vector is a three-dimensional oversampled (DFT) vector; and L?2, Nf?M?1, N?2, and L, M, N, and Nf are all integers.

Abstract: A precoding matrix indicating and determining method, including determining a precoding matrix indicator (PMI) having R groups of space-frequency information corresponding to R transmission layers, where the R groups of space-frequency information are used to determine a precoding matrix of each subband, and an rth group of space-frequency information in the R groups indicates P×L space domain vectors corresponding to an rth transmission layer in the R transmission layers, K frequency domain vectors corresponding to the rth transmission layer, and P×L×K coefficients corresponding to the rth transmission layer, where each of the P×L×K coefficients indicates a linear superposition coefficient of a vector operation result of a P×L space domain vectors and one of the K frequency domain vectors, R is a quantity of transmission layers, P is a quantity of polarization directions, and R, r, P, L, and K are all positive integers, and sending the PMI.

Abstract: This application provides a technical solution for rank indication, and especially when a CQI number is not configured or a CQI number is 1, a network device configures a rank indication restriction parameter as that at least one of ranks whose index numbers are 0, 1, 2, and 3 is allowed to be reported by the terminal device; or even if the network device does not perform the foregoing configuration, and none of the ranks whose index numbers are 0, 1, 2, and 3 is allowed to be reported, the terminal device may select at least one rank for RI reporting, so as to resolve a problem that a system cannot work. In addition, according to embodiments of this application, bit overheads required for RI reporting may further be reduced.

Abstract: A channel state information feedback method includes: generating, by a transmit-end device, codebook indication information of K transport layers, where K is an integer greater than or equal to 1; and for each of at least one of the K transport layers, the codebook indication information includes narrowband superposition coefficients of N sub-bands of the layer, where a quantity of the narrowband superposition coefficients of the N sub-bands is less than R(L?1)*N, N is an integer greater than or equal to 2, R is a quantity of polarization directions and R is an integer greater than or equal to 1, and L is a quantity of pieces of beam information used by the K transport layers and L is an integer greater than or equal to 2; and sending, by the transmit-end device, the codebook indication information.

Abstract: The present disclosure relates to channel state information (CSI) receiving methods and apparatus. One example method includes transmitting a pilot, and receiving feedback of W1 and W2 for each transport layer which are determined based on the pilot, where W1 and W2 are used to form a combined vector W for each transport layer, W=W1×W2, W1=[b1 b2 . . . bK], bi is a vector to be combined, W2=[X1 X2 . . . XK]T, Xi is a weighting coefficient corresponding to bi, K is a quantity of vectors in W1, K is a positive integer which is greater than 1, i is an integer, 1?i?K, and quantities of bits for feeding back at least two elements in W2 are different from each other.

Abstract: Embodiments of this application relate to the field of communications technologies, and disclose a precoding matrix configuration method and apparatus, to help improve performance of decoding data. The method may include: receiving first configuration information, where the first configuration information is used to configure M precoding matrices, M?2, and M is an integer; and aggregately sending a signal in N time domain units based on the first configuration information, where the signal is a signal obtained after precoding is performed by using a precoding matrix corresponding to each of the N time domain units, the precoding matrix corresponding to each time domain unit is one of the M precoding matrices, N?2, and N is an integer.

Abstract: The application provides a beam training method and a communications apparatus. The method includes: generating, by a terminal device, capability indication information, where the capability indication information is used to indicate that the terminal device can support simultaneous beam training in a maximum of N frequency bands, and N is an integer greater than or equal to 1; and sending, by the terminal device, the capability indication information. In this way, the network device may select a plurality of frequency bands at a time based on a capability of the terminal device to simultaneously perform beam training. Therefore, in an embodiments of this application, when the quantity N, of frequency bands for simultaneous training, supported by the terminal device is greater than 1, beam training may be simultaneously performed between the network device and the terminal device in a plurality of frequency bands.

Abstract: This application discloses a channel estimation method and apparatus, and relates to the field of communications technologies, to help reduce indication overheads. The method may include: generating and sending indication information. The indication information is used to indicate K N-dimensional spatial-domain component vectors, L M-dimensional frequency-domain component vectors, and a weight matrix, to indicate to construct an M×N-dimensional spatial-frequency matrix, or an M×N or N×M spatial-frequency matrix.

Abstract: Embodiments of the present application provide a parameter indication method and parameter determining method, a receive device, and a transmit device. The parameter indication method includes: generating indication information for each of a plurality of antenna panels, where the indication information is used to indicate an adjustment parameter of the antenna panel, and the adjustment parameter includes at least one of an amplitude adjustment parameter and a phase adjustment parameter; and sending the indication information. The embodiments of the present application further provide a parameter determining method, a receive device, and a transmit device. In the technical solutions provided in the embodiments of the present application, adjustment parameters of the plurality of antenna panels are fed back to adjust the plurality of antenna panels, so that a precoding vector constructed based on the plurality of antenna panels is more accurate.