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.

Abstract: This application provides a reference signal sending method, a reference signal receiving method, a network device, and a terminal device, to perform CSI (Channel State Information) measurement by using more precoding vectors (or precoding matrices), to measure more equivalent channels, thereby improving flexibility and a spatial degree of freedom of network device scheduling. The method includes: performing, by the network device, precoder cycling on a first reference signal by using at least two precoding vectors, to obtain a precoded first reference signal, where the precoded first reference signal is borne in a plurality of physical resource groups, and signals borne in any two adjacent physical resource groups correspond to different precoding vectors; and sending, by the network device, the precoded first reference signal to the terminal device by using the plurality of physical resource groups, where the first reference signal is used by the terminal device to perform CSI measurement.

Abstract: This application disclose a method for indicating and determining a precoding vector related to precoding technologies to increase an overall system performance gain. The method may include: generating indication information, and sending the indication information. The indication information is used to indicate a plurality of component vectors of a precoding vector and a combination coefficient of each component vector. The combination coefficient of the component vector includes at least one of the following types: a wideband amplitude coefficient, a narrowband amplitude coefficient, and a narrowband phase coefficient.

Abstract: This application provides a communication method and a communications apparatus. The method includes: generating, by a terminal device, first indication information, where the first indication information is used to indicate a precoding matrix, the precoding matrix is applied to at least one antenna panel and includes at least one precoding vector, each precoding vector includes a plurality of subvectors, each subvector corresponds to an antenna port on the antenna panel and includes two polarization vectors, and each polarization vector is generated by performing weighted combination on a plurality of basis vectors; and sending the first indication information. In embodiments of this application, accuracy of a codebook can be improved.

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: A transmission control method includes: receiving N pieces of transmission control information; and generating, based on the N pieces of transmission control information, transmission feedback information corresponding to transport blocks respectively scheduled by using the N pieces of transmission control information. Transport blocks can be accurately distinguished based on different effective transmission parameter group fields, and an effective feedback is provided.

Abstract: Embodiments of this application disclose a terminal device capability transmission method, apparatus, and system. A terminal device reports, to a network device, capability information used to indicate a channel state information CSI reporting capability of the terminal device. The capability information is associated with a quantity, supported by the terminal device in a time-domain unit, of ports of pilots used for CSI measurement, and is used to enable the network device receiving the capability information to learn the CSI reporting capability of the terminal device, thereby determining a CSI measurement configuration of the terminal device.

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: The application provides method for communicating channel state information (CSI) in a communication network. The method is as follows: An apparatus determines whether a length of CSI is less than a preset length; and adds a padding bit to the CSI when determining that the length of the CSI is less than the preset length, where a length of CSI obtained by adding the padding bit is consistent with the predetermined length. The CSI obtained by adding the padding bit is communicated in the communication network.

Abstract: The present invention belongs to the field of communications technologies, and discloses a channel state information CSI feedback method and an apparatus. The method includes: determining a codebook of at each transport layer CSI of user equipment UE, where the codebook of the CSI at each transport layer of the UE is: W=W1×W2, an element Xi in W2 is a weighting coefficient corresponding to each codeword in W1, and i is an integer greater than or equal to 1 and less than or equal to K; determining a quantity Ni of bits occupied by a quantized value of an ith element in W2, where quantized values of at least two elements in W2 occupy different quantities of bits; and feeding back the quantized value of the ith element to a network device based on Ni.

Abstract: Embodiments of the present invention provide user equipment, including: a transceiver module, configured to receive configuration information, where the configuration information is used to configure at least one physical resource block (PRB) bundling size; and a processing module, configured to determine a precoding resource block group (PRG) size based on the at least one PRB bundling size. The embodiments of the present invention further provide an access device. In technical solutions provided in the embodiments of the present invention, the PRG size is configured by configuring the PRB bundling size. In this way, there is no need to set dedicated signaling for configuring the PRG size. This helps reduce signaling overheads caused by configuring the PRG size.

Abstract: Embodiments can provide a precoding matrix indicating method, a precoding matrix determining method, a receive end device, and a transmit end device. In the precoding matrix indicating method, component matrices of an ideal precoding matrix and a weight of each component matrix can be determined based on at least one basic codebook. A dimension of each component matrix is the same as a dimension of the ideal precoding matrix, and a column vector of each component matrix is selected from column vectors of one of the at least one basic codebook. A precoding matrix indicator can be sent. The precoding matrix indicator can indicate the component matrices and the weight of each component matrix. With this, an ideal precoding matrix is approximately represented in a form of a weighted sum of a plurality of component matrices so that feedback overheads caused by feeding back a precoding matrix can be reduced.

Abstract: Embodiments of the present invention provide a channel measurement method. The method includes: obtaining, for a to-be-measured frequency band including at least one reporting subband and at least one missing subband, channel state information of each reporting subband and channel state information of each missing subband, where the channel state information of each reporting subband is obtained based on channel estimation, and the channel state information of each missing subband is obtained according to a reference rule with reference to channel state information of a reporting subband that is indicated by the reference rule and that is in the at least one reporting subband; and sending a measurement report of the to-be-measured frequency band to a transmit end device, where the measurement report includes the channel state information of each reporting subband in the at least one reporting subband.

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: This application provides a communication method, a communications apparatus, and a system. The method may include receiving, by a terminal device, a first group of precoded reference signals and a second group of precoded reference signals. The method may also include feeding back first indication information based on a channel state information (CSI) feedback-based transmission scheme, where the first indication information is used to determine a plurality of precoding vectors, at least one of the plurality of precoding vectors is determined by using the first group of precoded reference signals, and at least one of the plurality of precoding vectors is determined by using the second group of precoded reference signals.

Abstract: A method includes generating, by a processor, first indication information based on N reference signals, where N is an integer and N?2. The first indication information indicates a plurality of component vectors for constructing a precoding matrix and a superposition coefficient of each component vector of each of M precoding vectors for constructing the precoding matrix upon which a precoding of M reference signals is based, where M is an integer and 1?M<N. The method also includes transmitting the first indication information by way of an antenna.

Abstract: This application disclose a method for indicating and determining a precoding vector related to precoding technologies to increase an overall system performance gain. The method may include: generating indication information, and sending the indication information. The indication information is used to indicate a plurality of component vectors of a precoding vector and a combination coefficient of each component vector. The combination coefficient of the component vector includes at least one of the following types: a wideband amplitude coefficient, a narrowband amplitude coefficient, and a narrowband phase coefficient.

Abstract: This application provides a data transmission method and apparatus. The method includes: receiving, by a terminal device, a first reference signal sent by a network device; measuring, by the terminal device, a downlink channel based on the first reference signal, to obtain a channel status of the downlink channel; determining, by the terminal device, a target mode from a plurality of modes based on the channel status of the downlink channel, where information that is used to feed back channel state information (CSI) and that is sent by the terminal device in different modes of the plurality of modes is different; and sending, by the terminal device, indication information to the network device, where the indication information is used to indicate the target mode. The data transmission method and apparatus in the embodiments of this application are conducive to improve flexibility of feeding back CSI.

Abstract: This application provides a data transmission method and apparatus, and a system.