An apparatus for mapping data in a wireless communication system. The apparatus includes circuitry for generating a precoding matrix for multi-antenna transmission based on a precoding matrix indicator (PMI) feedback from at least one remote receiver where the PMI indicates a choice of precoding matrix derived from a matrix multiplication of two matrices from a first code book and a second codebook. The apparatus further includes circuitry for precoding one or more layers of a data stream with the precoding matrix and transmitting the precoded layers of data stream to the remote receiver.

A method and apparatus for channel state information feedback and a storage medium are provided according to the present disclosure. The method includes: performing by a terminal channel measurement according to a reference signal; selecting M subbands from K subbands of a CSI reporting band, and reporting to a base station the M subbands' Relative Power Indicator (RPI) and Phase Indicator (PI) of a weighted coefficient associated with a precoding codebook index, where M and K are integers greater than or equal to 1, M<K; each subband is a set of R resource blocks RB, where R is an integer greater than or equal to 1.

The present disclosure relates to a method for determining a precoding matrix indicator, a user equipment (UE), a base station (e.g., eNB), and a system. The method includes: receiving a reference signal sent by a base station; selecting, based on the reference signal, a precoding matrix from a codebook, where a precoding matrix W included in the codebook is a product of two matrices W.sub.1 and W.sub.2, where W.sub.1 is a block diagonal matrix, where each block matrix is a Kronecker product of a matrix A.sub.i and a matrix B.sub.i; and sending a precoding matrix indicator (PMI) to the base station, where the PMI corresponds to the selected precoding matrix, so that the base station obtains the precoding matrix according to the PMI.

A computer-implemented method comprising: monitoring transmissions representing estimation of a wireless channel, between at least one wireless access point (AP) and a plurality of wireless stations (STAs); at a training stage, training a machine learning model on a training dataset comprising: (i) a plurality dataframes of a standard beamforming protocol associated with at least some of the monitored transmissions, and (ii) labels indicating an association between the dataframes and the STAs; and at an inference stage, applying the trained machine learning model to a target transmission representing estimation of a wireless channel, to predict whether the target transmission was transmitted from one of the STAs.

The present disclosure provides a method of generating codebook in a wireless communication system with multiple antenna arrays, as well as a wireless communication system, base station and terminal using the codebook for communication. The method comprises steps of: providing a basic codebook which contains multiple pre-coding matrices; and assigning phase offsets to certain pre-coding matrices in the basic codebook to form a codebook with phase offset. The feedback overhead from a client to a base station side is reduced and a good precision of feedback for multi-antenna array is kept by applying the method of generating codebook and using the generated codebook in the wireless communication system, base station and terminal.

The present invention relates to a method for transmitting and receiving channel state information (CSI) and a device for same. Specifically, the method comprises the steps of: receiving setting information including information about a codebook; receiving a reference signal; measuring CSI on the basis of the reference signal; and transmitting the CSI, wherein the CSI is calculated on the basis of the codebook, which is formed by linear combination on the basis of multiple matrices, a first matrix of the codebook includes a plurality of column vectors set differently for each polarization of antenna ports, and the CSI includes precoding matrix indicators (PMIs) corresponding to indexes of the codebook.

A method for providing feedback about a MIMO channel between a transmitter and a receiver in a wireless communication system includes receiving a radio signal which includes one or more reference signals according to at least one reference signal configuration known at the receiver and indicating one or more antenna ports associated with the reference signals; estimating the MIMO channel based on measurements on the reference signals; determining a precoding vector or matrix based on the estimated MIMO channel, on one or more vectors or one or more combinations of vectors from at least one port-selection codebook and on a set of precoding coefficients, the port-selection codebook including vectors, each vector being associated with one of the antenna ports and having a single element which is one and the remaining elements being zeros; and reporting, a feedback to the transmitter which indicates the determined precoding vector or matrix.

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.

A method for operating a user equipment (UE) comprises receiving information about a channel state information (CSI) report; determining, based on the information, the CSI report including amplitude indicators and phase indicators of a total of K.sup.NZ coefficients; determining, based on a condition, whether a bitmap indicator is included in the CSI report, where the bitmap indicator identifies indices of the K.sup.NZ coefficients; and transmitting the CSI report which includes the bitmap indicator when the condition is not satisfied.

A method performed by a base station of enabling a User Equipment (UE) to determine a precoder codebook in a wireless communication system is provided. The base station transmits, to the UE, information regarding precoder parameters enabling the UE to determine the precoder codebook. The precoder parameters are associated with a plurality of antenna ports of the base station. The precoder parameters relate to a first dimension and a second dimension of the precoder codebook. The plurality of antenna ports comprises a number of antenna ports that is a function of a number of antenna ports in the first dimension, and a number of antenna ports in the second dimension.