A terminal according to an aspect of the present disclosure includes: a control section that determines a plurality of pieces of channel state information (CSI) corresponding to at least one group and an ID corresponding to each of the plurality of pieces of CSI, each of the at least one group corresponding to at least one channel measurement; and a transmitting section that transmits each of the plurality of pieces of CSI in an occasion corresponding to the ID. With this configuration, reduction of reliability of CSI can be prevented while reducing increase of UL overhead.

Apparatus and methods are provided for port selection codebook configuration. A user equipment (UE) may decode a channel state information (CSI) report configuration (CSI-ReportConfig) from a base station. The CSI-ReportConfig configuring a port selection codebook comprising a port selection matrix W.sub.1, a combinational coefficient matrix W.sub.2, and a frequency basis selection matrix W.sub.f. Based on the CSI-ReportConfig, the determines, for the port selection matrix W.sub.1, up to L CSI reference signal (CSI-RS) ports out of P CSI-RS ports configured for measuring and reporting CSI. For the frequency basis selection matrix W.sub.f, the UE determines up to Mv frequency basis out of N frequency basis. For the combinational coefficient matrix W.sub.2, the UE determines up to L*Mv entries per layer. The UE reports one or more of the port selection matrix W.sub.1, the combinational coefficient matrix W.sub.2, and the frequency basis selection matrix W.sub.f to the base station.

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 base station may transmit to a device an indication of codebook subset restriction (CBSR), which includes at least a restriction on a frequency basis. The device may receive the indication of CBSR, and may transmit to the base station channel state information (CSI) according to the received indication of CBSR. The indication of CBSR may also include a restriction on a spatial basis and restrict the device from reporting the CSI based on a subset of the frequency basis in addition to the spatial basis per configuration of the base station. The indication of CBSR may include a separately configured maximum allowed amplitude of a weighting coefficient for the spatial basis and the frequency basis, where the weighting coefficient is associated with a column vector of a precoding matrix used by the base station and the device. The number of frequency bases and the frequency compression units may be determined based on a number of different criteria, for example the number of antennas, the number of subbands, etc.

A user equipment (UE) for channel state information (CSI) feedback comprises a transceiver configured to receive, from a base station (BS), configuration information for the CSI feedback, the configuration information indicating a number of antenna panels (N.sub.g) at the BS and a codebook mode, wherein N.sub.g>1 and each of the antenna panels comprises antenna ports with a first polarization (P.sub.1) and antenna ports with a second polarization (P.sub.2). The UE further comprises a processor operably connected to the transceiver, the processor configured to identify the number of antenna panels (N.sub.g) at the BS, identify a codebook for the CSI feedback based on the codebook mode configured between a first codebook mode and a second codebook mode, and generate the CSI feedback using the identified codebook. The transceiver is further configured to transmit the generated CSI feedback to the BS.

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.

A user equipment (UE) for channel state information (CSI) comprises receiving configuration information for K CSI reports, wherein the configuration information includes resource allocation information for an uplink control information (UCI) transmission that includes UCI comprising N UCI parts, calculating the K CSI reports and partitioning the K CSI reports into N parts, determining an available number of information bits (B1) for the UCI transmission according to the resource allocation information, determining a required number of information bits (B2) for the UCI transmission according to the calculated K CSI reports, determining whether the B2 exceeds the B1; and transmitting, to the BS over one slot of an uplink channel, a first part of the N UCI parts including a first of the N parts of the K CSI reports when the B2 exceeds the B1, wherein K and N are positive integers.

A method implemented by a wireless transmit/receive unit (WTRU) having multiple antennas includes determining, by the WTRU, information that is associated with a baseband channel and that indicates any of measurement information and channel information, and transmitting, by the WTRU, a signal for requesting baseband beam tracking, on condition that any of: (1) the WTRU determines, according to the indicated information, that: (i) system performance is degraded in a hybrid beamforming transmission, and (ii) re-estimation of the baseband channel is part of a current link adaptation procedure, and (2) detailed baseband channel information was not part of a multiple-in multiple-out (MIMO) setup procedure.

Apparatuses, methods, and systems are disclosed for Type-II port-selection codebook generation. One apparatus includes a processor and a transceiver that receives a set of CSI-RS. The processor identifies a set of CSI-RS ports based on the set of CSI-RS. The processor selects a subset of CSI-RS ports from the identified set of CSI-RS ports based on a free selection of the respective CSI-RS ports from the identified CSI-RS ports. The processor generates, based on the set of CSI-RSs, at least one amplitude coefficient indicator and at least one phase coefficient indicator for each selected CSI-RS port generates a CSI report comprising a Type-II port-selection codebook corresponding to the generated coefficients and the subset of CSI-RS ports.

This application provides a communication method and apparatus, and relates to the field of communication technologies. In the method, a first communication apparatus determines a first index indicating a first precoding vector, and sends the first index to a second communication apparatus. The second communication apparatus receives the first index from the first communication apparatus, determines the first precoding vector based on the first index, and precodes data based on the first precoding vector. The first precoding vector includes spatial angle information and spatial depth information of a channel between the first communication apparatus and the second communication apparatus.