A method, network node and antenna system providing multilayer digital sectors for advanced antenna systems are provided. According to one aspect, a first set of beams on a first frequency are steered to different directions such that only sidelobes of beams of the first set overlap in gaps between the main beams of the first set, while a second set of at least one beam on a second frequency are steered into at least one gap between the beams of the first set.

Methods, systems, and devices for wireless communications are described. A codebook adaptation may be performed for a flexible user equipment (UEs) to determine a codebook for a physical configuration of the UE. For example, if the UE determines that the physical configuration does not correspond to a pre-loaded codebook in its memory, the UE may provide information about the physical configuration to a base station to determine a corresponding codebook. Additionally, the UE may request that the base station provide channel information to assist with the codebook determination. In some cases, this request may indicate for the base station to allocate a specific number of channel state information reference signal symbols that the UE can use for the codebook determination. Additionally or alternatively, the UE may generate the codebook internally and then signal to the base station a request for a beam refinement procedure with the generated codebook.

A channel measurement method and a communication apparatus are provided. The method includes: generating channel information, where the channel information indicates one or more receive beam vectors and one or more weighting coefficients, each of the one or more weighting coefficients corresponds to one receive beam vector, the one or more receive beam vectors and the one or more weighting coefficients corresponding to the one or more receive beam vectors are used to determine a channel of at least one frequency domain unit between a terminal device and a network device, the one or more receive beam vectors are selected from a receive beam vector set, and the receive beam vector set is determined based on a predefined base vector set; and sending the channel information.

A UE determines a PMI, by performing at least the following: determining an intermediate set of vectors from a FD codebook; forming a subset of the intermediate set of vectors; mapping the subset of vectors to a combinatorial indicator; and forming the PMI at least from the combinatorial indicator. The UE sends the PMI toward a wireless network. A base station receives the PMI from the UE. The PMI includes a combinatorial indicator that maps to a subset of vectors from the FD codebook. The base station determines, using at least the received PMI, information from at least the FD codebook to apply to data for transmission toward the UE.

This application provides a resource indication method and a communication apparatus. The method includes: The second node receives first indication information from the first node, where the first indication information includes first resource information, and the first resource information is associated with a first reference signal. The second node determines the first resource information based on the first indication information, where the first resource information is for limiting sending of a to-be-sent signal on a first resource indicated by the first resource information. In this way, the sending of the to-be-sent signal by the second node on the first resource is limited, so that interference of the second node to the third node can be reduced, and network performance and spectrum efficiency can be improved.

The teachings herein present a method and apparatus that implement and use a factorized precoder structure that is advantageous in terms of performance and efficiency. In particular, the teachings presented herein disclose an underlying precoder structure that allows for certain codebook reuse across different transmission scenarios, including for transmission from a single Uniform Linear Array (ULA) of transmit antennas and transmission from cross-polarized subgroups of such antennas. According to this structure, an overall precoder is constructed from a conversion precoder and a tuning precoder. The conversion precoder includes antenna-subgroup precoders of size N.sub.T/2, where N.sub.T represents the number of overall antenna ports considered. Correspondingly, the tuning precoder controls the offset of beam phases between the antenna-subgroup precoders, allowing the conversion precoder to be used with cross-polarized arrays of N.sub.T/2 antenna elements and with co-polarized arrays of N.sub.T antenna elements.

A method of transmitting an uplink signal for a terminal configured to support multiple TTI (transmission time interval) lengths in a wireless communication system, includes mapping rank indicator (RI) information to elements on a column of an element matrix in a descending order of a row index from a maximum value of row indexes of the column; mapping ACK/NACK (acknowledgement/non-acknowledgement) information to the elements on the column in a descending order of the row index from a maximum value of the row indexes of the column among remaining elements except the elements of the column used for the RI information; and transmitting the uplink signal including the RI information and the ACK/NACK information.

A method, wireless device and network node for determining an indication of a precoder are provided. According to one aspect, a method in a wireless device includes determining and the indication of the precoder from a codebook, the indication comprising a first beam phase parameter and a second beam phase parameter corresponding to a first beam and a second beam respectively. The first beam phase parameter takes on one of a first integer number of phase values and the second beam phase parameter takes on one of a second integer number of phase values. At least one of the following conditions apply: the second integer number of phase values is less than the first number of phase values, and the second frequency-granularity is greater than the first frequency-granularity. The method includes transmitting the determined indication of a precoder to the network node.

Precoding matrix indicator (PMI) feedback for Type II channel state information (CSI) feedback in new radio (NR) multiple input, multiple output (MIMO) operations is discussed. According to various aspects, a user equipment (UE) determines a plurality of CSI feedback components and identifies a set of discarded ones of these components based on a particular component value of a precoding matrix indicator (PMI) component. The UE may then generate an adjusted CSI report by adjusting how the discarded feedback components are treated. The resulting adjusted CSI report may then be transmitted to a serving base station.

In one aspect, a method for wireless communication includes transmitting a first message indicating a precoding matrix identifier configured to identify a particular precoding matrix for precoding by another wireless communication device for at least one future transmission; and receiving a second message indicating information about whether the particular precoding matrix was or will be used for the at least one future transmission. In another aspect, a method for wireless communication includes receiving a first message indicating a precoding matrix identifier configured to identify a particular precoding matrix for precoding by the wireless communication device for at least one future transmission; and transmitting a second message indicating information about whether the particular precoding matrix was or will be used for precoding for the at least one future transmission. Other aspects and features are also claimed and described.