A communication device for providing a channel state information, CSI, feedback in a wireless communication system includes a transceiver to receive, from a transmitter a radio signal via a time-variant, frequency-selective MIMO channel, the radio signal including downlink reference signals according to a reference signal configuration including a number of antenna ports, and downlink signals including the reference signal configuration; and a processor. The processor estimates an explicit CSI in the frequency domain using measurements on the downlink reference signals on the radio channel, selects a Doppler-delay precoder matrix (W) for a composite Doppler-delay-beam three-stage precoder, calculates either one or more of a channel quality indicator, CQI, and/or a precoder matrix indicator, PMI, and/or a rank indicator, RI, and reports to the transmitter the CSI feedback including either one or more of the CQI, and/or the PMI and/or the RI.

Aspects presented herein enable updating the codebook configuration upon the changing of the cover or case of the UE. The apparatus applies a first codebook from a plurality of preconfigured codebooks. The apparatus detects a change of a cover state of the UE, wherein the change alters a transmission beam pattern at the UE. The apparatus applies a second codebook from the plurality of preconfigured codebooks based on the change of the cover state.

Devices and methods for detection of active return loss for an antenna element of a plurality of antenna elements of a phased array antenna are provided. An exemplary device can convert a voltage differential at an input of a power amplifier (PA) to first current. The device can convert a coupled voltage corresponding to a signal transmitted from the PA to a respective antenna element, to a second current. The device can convert a reflected voltage corresponding to a signal reflected from the respective antenna element, to a third current. The device can convert the first current, the second current, and the third current to an output voltage at a generator output. The device can further have a controller that can adaptively generate codebooks for transmission based on the output voltage.

Provided are a weight sending method and apparatus, a storage medium and an electronic device. The weight sending method includes: dividing a plurality of cells to obtain one or more subnets: for any first subnet of the one or more subnets, determining a subnet target broadcast beam weight set of the first subnet from preset weights of a member cell according to at least one of: cell coverage of the member cell included in the first subnet or inter-cell interference of the member cell included in the first subnet; and sending the determined subnet target broadcast beam weight set to the first subnet.

Wireless communications systems and methods related to CSI feedback are provided. A user equipment (UE) receives an indication of a restricted set of frequency domain (FD) beamforming components and one or more channel state information reference signals (CSI-RSs). The UE may transmit channel state information (CSI) report indicating a plurality of precoding coefficients based on the received one or more CSI-RSs and the restricted set of FD beamforming components.

A method for operating a user equipment (UE) comprises receiving channel state information (CSI) reporting configuration information including a CSI reporting band and a frequency granularity of CSI reporting, where the CSI reporting band is within a bandwidth part (BWP) comprising M physical resource blocks (PRBs), and the frequency granularity of CSI reporting is based on whether M<N, where N is a threshold; identifying the frequency granularity of CSI reporting; generating a CSI report with the identified frequency granularity, wherein the CSI report includes at least one of a precoding matrix indicator (PMI) and a channel quality indicator (CQI); and transmitting the CSI report over an uplink (UL) channel.

A method for operating a user equipment (UE) comprises receiving configuration information for a CSI report. The configuration information includes information to: configure a codebook and parameters for the codebook, the codebook comprising a precoding matrix indicator (PMI) indicating a set of components S to represent N.sub.3 precoding matrices, where N.sub.3≥1; and partition the PMI into two subsets, a first PMI subset indicating a first subset of components S1 from the set of components S, and a second PMI subset indicating a second subset of components S2 from the set of components S different from the first subset of components S1. The method further comprises determining the CSI report based on the configuration information, the CSI report including the second PMI subset indicating the second subset of components S2, and transmitting the determined CSI report over an uplink (UL) channel.

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.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive a configuration including a plurality of codebook subset restrictions. The UE may identify a codebook subset restriction, of the plurality of codebook subset restrictions, to be applied to precoding matrix indicator (PMI) selection associated with a slot. The UE may transmit a channel state information (CSI) report including an indication of a PMI selected based at least in part on the identified codebook subset restriction. Numerous other aspects are described.

Apparatuses and methods for high resolution CSI codebook is provided. The method includes receiving configuration information about a channel state information (CSI) report, the configuration information including a parameter d≥1, where d is a number of principal components; determining left principal component vectors; determining right principal component vectors; determining principal singular values; and transmitting the CSI report including a precoding matrix indicator (PMI), the PMI indicating the left principal component vectors, the right principal component vectors, and the principal singular values, wherein at least one of the left principal component vectors, the right principal component vectors, and the principal singular values are selected from adaptive codebooks.