The present disclosure discloses a codebook feedback method, a terminal device and a network device. The codebook feedback method, comprising: selecting, by a terminal device, M frequency domain Discrete Fourier Transform (DFT) vectors from a DFT array; determining, by the terminal device, a first frequency domain DFT vector indication set from a plurality of frequency domain DFT vector indication sets according to the M frequency domain DFT vectors, wherein an indication of the M frequency domain DFT vectors is equivalent to a first frequency domain DFT vector indication in the first frequency domain DFT vector indication set, and M is a positive integer; and sending, by the terminal device, an indication message to the network device, wherein the indication message is used for indicating the first frequency domain DFT vector indication set.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a wireless communication device may generate a Legendre precoder for transmission on a multiple-input multiple-output channel based at least in part on computing Legendre polynomials for a quantity of transmit antennas. The wireless communication device may transmit a communication using the Legendre precoder. Numerous other aspects are provided.

Wireless network interfaces that are capable of transmitting and/or receiving beamformed radiofrequency (RF) signals may be assisted by the use of codebooks. Electronic devices with memory to store a database of codebooks may be used to increase the number of entries available for operation. The database of codebooks may employ environmental parameters to improve efficiency of the wireless network interface. Methods for calibration of electronic devices and/or adjustment and selection of codebooks based on the parameters are also described. The calibration may employ a testing chamber that measure powers at in a limited number of angles.

A method for transmitting Physical Uplink Shared Channel (PUSCH) performed by a User Equipment (UE) in a wireless communication system may include receive downlink control information (DCI) for uplink (UL) transmission scheduling; and performing codebook based PUSCH transmission based on precoding information included in the DCI.

This application relates to a communications method and apparatus, and a device. The communications method includes: A terminal device determines a first codeword set, where the first codeword set includes a first codeword, the first codeword is a 4×1 matrix, and each element in the matrix is a non-zero element.

A method and network node for management of beams radiated by a phased array antenna of a network node to comply with regulatory or other constraints are provided. According to one aspect, a network node is configured to selectively transmit radio frequency beams in a plurality of directions on a plurality of layers to a plurality of wireless devices. The network node includes processing circuitry configured to direct and beams to a first set of directions while suppressing energy radiated in a second set of directions according to algorithms that modify a precoder to achieve a distribution of radiated energy without computationally burdensome optimization algorithms.

A user equipment (UE) is configured to vary a number of chains in uplink or downlink communications with a base station (BS). The UE includes a processor coupled to a transceiver. The processor is configured to: identify a full-chain beam for a downlink reception based on a beam sweeping; determine a number of activated chains for an uplink transmission; and determine a sub-chain uplink transmission beam.

The present disclosure relates to a communication method and system for converging a 5th-Generation (5G) communication system for supporting higher data rates beyond a 4th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. A method of operating a user equipment (UE) for CSI feedback is provided. The method comprises receiving configuration information for the CSI feedback from a base station (BS) and identifying a number of antenna ports for the CSI feedback. The method comprises, if the number of antenna ports is <16, identifying a first codebook for the CSI feedback corresponding to a rank value of 3 or 4, and, if otherwise, identifying a second codebook for the CSI feedback corresponding to the rank value of 3 or 4. The method comprises generating the CSI feedback using the identified codebook and transmitting the generated CSI feedback to the BS. The first codebook has a structure that partitions the antenna ports into two equal partitions. The second codebook has a structure that partitions the antenna ports into four equal partitions by partitioning each partition into two equal sub-partitions.

A network entity comprises a plurality of antenna elements arranged in one or more two dimensional (2D) arrays having one or more columns and rows. The network entity configured to determine at least one set of one or more precoding vectors related to the plurality of antenna elements, wherein each set of precoding vectors is associated with a different Kronecker product tradeoff parameter L≥1; and transmit, at least one set of a plurality of Cell Specific Reference Signals (CRS) to be used to estimate channel state information (CSI) based on the at least one set of precoding vectors and/or at least one Kronecker product tradeoff parameter L.

A network node for a Frequency Division Duplex, FDD, wireless communication network is provided. The network node includes processing circuitry configured to determine a transformation matrix for transforming an uplink codebook to a downlink codebook where the transformation matrix is based at least in part on channel state information, CSI. The processing circuitry is further configured to determine a first uplink codebook based at least in part on uplink signals, determine a first downlink codebook based at least in part on the transformation matrix and the first uplink codebook, and cause transmission of downlink signals to a wireless device based at least in part on the first downlink codebook.