Methods, systems, and devices for wireless communications are described in which a receiving device, such as a receiving user equipment (UE) or vehicle, may provide channel state information (CSI) in which two or more parameters associated with the CSI are provided in a single joint indication. A transmitting device may transmit one or more reference signals and the receiving device may perform one or more measurements on the received reference signal(s). Based on the one or more measurements, the receiving device may determine one or more CSI parameters, such as a rank indicator, channel quality indicator, precoding matrix indicator, or combinations thereof, that may be provided to the transmitting device in a joint indication.

A method of a UE transmitting a codebook based uplink signal in a wireless communication system, the method comprising: transmitting capability information about UE capability that maintains differences between phase values applied to antenna ports for uplink signal transmission; receiving configuration information for determining a codebook subset related to the uplink signal transmission based on the capability information; receiving DCI for determining a precoding matrix applied to the uplink signal transmission; determining a precoding matrix to be applied for the uplink signal transmission, based on the DCI, from the codebook subset determined based on the configuration information; and transmitting the uplink signal, based on the determined precoding matrix, wherein, based on that the differences between phase values are maintained at some antenna ports, the codebook subset includes at least one specific precoding matrix applying different phase values to the antenna ports included in some or all of some antennas.

A CBSR configuration can include a set of restricted beams. Each restricted beam can be constrained by a configured maximum allowed gain value. A set of beams including one or more restricted beams can be selected. A set of precoder coefficients can be determined for each selected beam. A function of the set of precoder coefficients can satisfy the configured maximum allowed gain value. The function can be proportional to a square root of an average of squared values of amplitudes of members of the subset. A CSI report can be transmitted. The CSI report can include at least an indicator of the set of selected beams and an indicator of the set of precoder coefficients corresponding to each selected beam.

A method and an apparatus for feeding back channel state information (CSI) of user equipment (UE) in a communication system are disclosed. The method comprises the steps of: receiving, from a base station, configuration information related to a plurality of CSI reports; identifying the setting of the plurality of CSI reports corresponding to a plurality of measurement resources, on the basis of the configuration information; generating a first CSI report corresponding to a first measurement resource and a second CSI report corresponding to a second measurement resource when the plurality of CSI reports are set; and transmitting the first CSI report and the second. CSI report to the base station.

Methods, apparatus, and computer program products for a user equipment receiving CSI-RS and computing channel support information. Based on the CSI, the UE derives tap locations of channel support, depending on the observed channel and used subcarrier spacing. The deriving can additionally be done in relation to power class and window size. The UE apprises a base station of those tap locations of the channel support and also informs the base station of the strongest tap locations, which can be done in various ways comprising a bit mask. Methods, apparatus, and computer program products for a base station to send CSI-RS to a UE for computing CSI feedback. The CSI-RS resources can be for one or multiple transmit receive points. The base station receives back an indication of tap locations and a bit mask and builds information on tap locations by combining that received indication and bit mask.

The present disclosure describes methods, device, system that provide a codebook indication operation. In one example, a codebook indication method includes: receiving by a terminal device, a transmission parameter indication information indicating an index of one codebook subset configuration of three codebook subset configurations in the terminal device from a base station, wherein the three codebook subset configurations in the terminal device are related to fully coherent, partial coherent, and incoherent respectively, and the codebook subset configuration related to fully coherent includes M indexes, the codebook subset configuration related to partial coherent includes N indexes, and the codebook subset configuration related to incoherent includes K indexes, wherein M is an integer larger than N, and N is larger than K; and determining a transmission layer and precoding matrix associated with the index according to the transmission parameter indication information.

Provided are a method and a device for channel state information, terminal, and network side, and a storage medium. The method includes: receiving beamformed CSI-RSs, or the beamformed CSI-RSs and frequency domain basis vector indication information transmitted by a network side by means of antenna ports, where beams used in beamforming are determined based on spatial domain basis vectors or based on the spatial domain basis vectors and frequency domain basis vectors, and the spatial domain basis vectors and the frequency domain basis vectors are determined based on an uplink channel; determining port indication information and a port combination coefficient for data transmission based on the beamformed CSI-RS or the beamformed CSI-RS and the frequency domain basis vector indication information; and feeding back the port indication information and port combination coefficient to the network side for determining precoding of downlink transmission data at the network side.

This application provides a method for obtaining channel information and a communications apparatus. The method includes: A first device sends a first reference signal to a second device, where density of the first reference signal is less than or equal to density of a second reference signal, and the second reference signal is a normal-density reference signal; the first device receives first channel state information CSI from the second device; and the first device obtains second CSI based on the first CSI and a first neural network model, where the second CSI is used to indicate channel information between the first device and the second device. The first neural network model is deployed on a side of the first device, to reduce transmission overheads of the first device and/or feedback overheads of the second device.

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.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may receive a first configuration of one or more channel state information reference signal resources and a second configuration of a channel state information report associated with the one or more channel state information reference signal resources. In some cases, the second configuration may include at least one of an indication of a codebook, a set of codebook restriction sets, and a configured bandwidth. The UE may then identify a mapping between one or more frequency-domain subbands of the configured bandwidth and each codebook restriction set of the set of codebook restriction sets, and transmit, to the base station, a report indicating one or more precoding matrix indicators from the codebook for each of the one or more frequency-domain subbands based on the mapping.