According to one embodiment of the present specification, a method by which a terminal can report beam information in a wireless communication system can be provided, and the method by which a terminal reports beam information comprises: obtaining information related with beam reporting from a base station; triggering beam reporting; receiving a signal related with beam reporting from the base station; measuring the signal related with beam reporting; and reporting the beam information to the base station based on the measured signal, wherein the beam information includes information on best beams among all available beams and the beam information can be reported based on reporting configuration.

A user equipment (UE) in communication with a base station (BS) is disclosed that includes a receiver that receives Channel State Information (CSI)-Reference Signals (RSs) from the BS, a processor that generates CSI based on the CSI-RS and performs CSI omission, and a transmitter that transmits, to the BS, CSI reports including the CSI where one or more linear combination (LC) coefficients are omitted based on the CSI omission. Further, in the CSI omission, the processor prioritizes LC coefficients based on a predetermined priority rule and the processor also determines the omitted one or more LC coefficients based on the prioritized LC coefficients. In other aspects, a method for a UE and a wireless communication system are disclosed.

Systems and methods for multi-beam Channel State Information (CSI) reporting are provided. In some embodiments, a method of operation of a second node connected to a first node in a wireless communication network for reporting multi-beam CSI includes reporting a rank indicator and a beam count indicator in a first transmission to the first node. The method also includes reporting a cophasing indicator in a second transmission to the first node. The cophasing indicator identifies a selected entry of a codebook of cophasing coefficients where the number of bits in the cophasing indicator is identified by at least one of the beam count indicator and the rank indicator.

In this way, feedback for both a rank indicator and a beam count indicator may be possible which may allow robust feedback and variably sized cophasing and beam index indicators.

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, systems, and devices for channel state information feedback based on full channel estimation are described. The method may include receiving a set of beamformed reference signals from a transmit device via a set of receive beams of the receive device, each beamformed reference signal of the set of beamformed reference signals associated with a corresponding transmit beam of a set of transmit beams of the transmit device, determining, based on the set of beamformed reference signals, a channel matrix representative of a communications channel between the receive device and the transmit device, and transmitting, to the transmit device, channel state information based on the channel matrix.

Methods, systems, and devices for wireless communications are described. A station (STA) may receive a null data packet (NDP) on a plurality of subcarriers, and the STA may generate a channel state information (CSI) matrix for each subcarrier of the plurality of subcarriers. After generating a CSI matrix for a subcarrier, such as at least one subcarrier, the STA may scale each value in the CSI matrix using a power-of-two value to minimize complexity. Specifically, instead of scaling each value in the CSI matrix to a value between zero and one using divisions (for example, which may be computationally expensive), the STA may use shifting to scale each value in the CSI matrix. The STA may then quantize the scaled values in the CSI matrix for reporting, and the STA may transmit the quantized, scaled values in the CSI matrix in a CSI report.

A network node signals to a wireless communication device which precoders in a codebook are restricted from being used. The network node in this regard generates codebook subset restriction signaling that, for each of one or more groups of precoders, jointly restricts the precoders in the group by restricting a certain component (e.g., a certain beam precoder) that the precoders in the group have in common. This signaling may be for instance rank-agnostic signaling that jointly restricts the precoders in a group without regard to the precoders transmission rank. Regardless, the network node sends the generated signaling to the wireless communication device.

An approach is described that includes receiving a CSI report, where the CSI report includes a channel quality indicator (CQI), a rank indicator (RI), and a precoding matrix indicator (PMI). The approach further includes constructing a precoding matrix based on a linear combination of a plurality of mutually orthogonal digital Fourier transformation (DFT) spatial beams, and determining a number of bits for the PMI of the precoding matrix. The approach also includes determining a space frequency matrix based, at least in part, on the number of bits for the PMI and the precoding matrix, and compressing the space frequency matrix. Finally, the approach includes determining a compressed PMI based, at least in part, on the space frequency matrix.

A channel measurement method includes a network device obtains first information and obtains third downlink channel information based on the first information. The first information is obtained based on second information and third information, the second information is obtained based on first downlink channel information obtained by a terminal device through measurement, and the third information is obtained based on uplink channel information and/or second downlink channel information obtained by the terminal device through measurement. The network device considers auxiliary information in a process of reconstructing downlink channel information, so that precision of the reconstructed channel information is improved.

Methods, systems, and devices for wireless communications at a first user equipment (UE) are described. The first UE may receive, from a second UE over a sidelink channel, a first channel state information report, a second channel state information report, and a first transmission configuration indicator, The first UE may select at least one of the first channel state information report or the second channel state information report to be canceled based on receiving an indication associated with the first transmission configuration indicator. The first UE may cancel information included in at least one of the first channel state information report or the second channel state information report based at least in part on the selecting. The first UE may receive a data transmission based at least in part on the cancelling.