Abstract: Certain aspects of the present disclosure provide techniques for channel state information (CSI) reporting with frequency domain (FD) compression. A method that can be performed by a user equipment (UE) includes determining the size of the intermediate set based on one or more parameters included in the CSI report configuration, determining one or more FD bases for each layer based on the intermediate set, wherein the one or more FD bases are characterized by an M value indicative of a number of the one or more FD bases and based on the CSI report configuration, and reporting the one or more FD bases for each layer based on the size of the intermediate set.

Abstract: Certain aspects provide techniques for precoder matrix quantization for compressed channel state information (CSI) feedback. A method for wireless communications by a user equipment (UE) includes receiving a CSI report configuration for frequency domain compressed precoder matrix feedback. The CSI report configuration configures the UE to report, for a plurality of selected beams at a plurality of time domain taps, a frequency domain compression basis vector and a plurality of linear combination coefficients associated with the frequency domain compression. For each of the beams, the UE groups the time domain taps into at least first and second groups. The groups each can have zero, one, or more than one time domain taps. The UE quantizes the corresponding linear combination coefficients and/or frequency domain compression basis vectors based on the grouping.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment may perform channel state information (CSI) measurements on one or more reference signal transmissions from a base station; determine, based at least in part on the CSI measurements, a set of non-zero linear combination complex coefficients for weighting and co-phasing for a linear combination of a plurality of frequency domain basis vectors and a plurality of spatial domain basis vectors; and transmit a CSI feedback, wherein a first part of the CSI feedback includes at least an indication of a number of the set of non-zero linear combination complex coefficients with regard to all layers of a communication link between the UE and the base station. Numerous other aspects are provided.

Abstract: Aspects described herein relate to receiving a configuration for cross-link interference (CLI) measurement reporting, wherein the configuration includes, for each component carrier of one or more component carriers, one or more parameters for measuring signals on the component carrier, and a resource setting indicating resources of the component carrier over which to measure signals. One or more measurements of signals received on the resources indicated by the resource setting for the component carrier can be measured based at least in part on the one or more parameters, and reported to a base station.

Abstract: Aspects of the present disclosure relate to wireless communication. In some aspects, a user equipment may determine at least one of: a first number of coefficients to be included in a first set of coefficients in a transfer domain that characterize compressed channel state information (CSI) for a first layer, or a first quantization scheme to be used to interpret the first set of coefficients. The UE may determine at least one of: a second number of coefficients to be included in a second set of coefficients in the transfer domain that characterize the compressed CSI for a second layer, or a second quantization scheme to be used to interpret the second set of coefficients. The UE may transmit a report that identifies the first set of coefficients and the second set of coefficients based at least in part on the determination(s). Other aspects are provided.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a base station may determine that a user equipment (UE) is to use a differential reporting mode based at least in part on a channel state information (CSI) report from the UE. The base station may transmit to the UE, signaling to cause the UE to use the differential reporting mode based at least in part on determining that the UE is to use the differential reporting mode. Numerous other aspects are provided.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, an aerial user equipment (UE) may measure a first offset associated with a downlink frame based at least in part on a time when a downlink signal is received from a terrestrial base station. The aerial UE may determine a second offset corresponding to a starting time for the downlink frame at the terrestrial base station. The aerial UE may transmit an uplink message in an uplink frame using a timing advance that is based at least in part on a value of the first offset and a value of the second offset relative to a starting time associated with a global navigation satellite system frame duration. Numerous other aspects are described.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive a sounding reference signal (SRS) configuration that indicates a maximum number of SRS ports and whether the UE is permitted to determine an actual number of SRS ports to be used for SRS transmission that is different from the maximum number of SRS ports. The UE may determine the actual number of SRS ports to be used for SRS transmission based at least in part on the SRS configuration. The UE may transmit one or more SRSs using the actual number of SRS ports. Numerous other aspects are provided.

Abstract: Methods, systems, and devices for wireless communications are described that provide for channel state information (CSI) feedback for multiple discrete Fourier transform (DFT) beams on multiple transmission layers. A user equipment (UE) may report a total number of non-zero power DFT beams across all of the transmission layers. The UE may be configured with a total number of leading beams (Ktotal) across all of the transmission layers for which to provide high quantization feedback. When the total number of non-zero DFT beams across all the transmission layers exceeds the configured total number of leading beams across all the transmission layers, the UE may report high-resolution quantization feedback for Ktotal non-zero power precoding coefficients having the highest amplitude coefficients, and may report low-resolution quantization feedback for the remaining non-zero power precoding coefficients. A base station may receive the CSI feedback to determine a precoding matrix.

Abstract: Certain aspects of the present disclosure provide techniques for a coefficients report for compressed channel state information (CSI) feedback. A method for wireless communication by a user equipment (UE) includes receiving a CSI report configuration configuring the UE for reporting precoding matrix information including, a plurality of selected beams L, a frequency domain compression matrix F for each of the L beams at each of a plurality of taps M in the time domain, and a subset of a plurality of linear combination coefficients associated with the frequency domain compression matrices and beams. The UE determines the coefficients based on a first evaluation that is, for each beam, an evaluation of the amplitude of the coefficients across the taps, and a second evaluation and a evaluation that is, for each tap, an evaluation of the amplitude of the linear combination coefficients across the beams. The UE reports the first and second evaluations.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment may transmit, in a first part of two-part channel state information (CSI), a rank indication (RI) and an indication of one or more numbers of first transfer domain coefficients to be used to characterize compressed CSI for one or more layers; and transmit, in a second part of the two-part CSI, an indication of one or more numbers of second transfer domain coefficients to be used to characterize compressed CSI for one or more beams for the one or more layers. Numerous other aspects are provided.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment may determine a first decoding result for a plurality of downlink control channels of a diversity enhancement based non-coherent joint transmission communication and a second decoding result for a plurality of data channels corresponding to the plurality of downlink control channels; and selectively provide feedback regarding the first decoding result and feedback regarding the second decoding result, the feedback regarding the first decoding result indicating whether reception of one or more downlink control channels, of the plurality of downlink control channels, is successful, and the feedback regarding the second decoding result indicating whether decoding of a codeword of the plurality of data channels is successful. Numerous other aspects are provided.

Abstract: Certain aspects of the present disclosure provide techniques for reporting channel state information (CSI) with spatial and time domain compression.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive an indication that beam switching without an explicit beam indication or activation is allowed. The UE may transmit a channel state information (CSI) report identifying a selected beam. The UE may selectively switch to the selected beam in accordance with the indication. Numerous other aspects are described.

Abstract: Methods, systems, and devices for wireless communications are described. In some systems, a user equipment (UE) may report basis subset selection for a set of beams, where the basis vectors are used for frequency domain compression. To reduce reporting overhead, the UE may transmit two reports indicating the basis vectors. The first report may include first information for the basis vectors and is of a known payload size to both the UE and a base station, while the second report may include second information for the basis vectors and may have a payload size dependent on the first information. The base station may decode the first report and may use the decoded first information to decode the second report. Based on the first and second information, the base station may determine the reported set of basis vectors to use for frequency domain compression and may determine non-zero precoding coefficients.

Abstract: Methods, systems, and devices for wireless communication are described. In wireless systems supporting multiple-input, multiple-output (MIMO) transmissions, devices may implement beam-forming to improve reliability of communications. A user equipment (UE) may select a set of beams, and corresponding beam indices, for communication based on reference signals received from a base station. The UE may determine values corresponding to each of the beam indices using a scalable set of tables. For example, the UE may select a subset of the tables based on the number of selected beams, and may determine the values based on these tables. In this way, the UE may efficiently store sets of tables for multiple different configurations. The UE may sum the corresponding values to obtain a combination index value, and may transmit the combination index value to the base station. The base station may determine the selected beams based on this combination index value.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive, from a base station (BS), a first signaling communication that configures a plurality of transmit precoder matrix indicator (TPMI) and sounding reference signal (SRS) resource indicator (SRI) pairs. The plurality of TPMI and SRI pairs may be for transmitting respective physical uplink shared channel (PUSCH) communications to the BS. The UE may receive, from the BS, a second signaling communication that indicates an update to a TPMI and SRI pair of the plurality of TPMI and SRI pairs. The UE may transmit, to the BS, a PUSCH communication, of the respective PUSCH communications, based at least in part on the update to the TPMI and SRI pair. Numerous other aspects are provided.

Abstract: Methods, systems, and devices for wireless communication are described. Neural networks may assist user equipments (UEs) and base stations in performing various operations related to wireless communications. For example, neural networks may be used to generate non-orthogonal cover codes for transmitting reference signals such as channel state information-reference signals (CSI-RSs). A base station may transmit, to a UE, a CSI-RS associated with a non-orthogonal cover code of a set of non-orthogonal cover codes. Using the CSI-RS, the UE may perform a channel estimation procedure that corresponds to the non-orthogonal cover code. Based on the channel estimation procedure, the UE may transmit a feedback message to the base station that indicates a channel quality parameter. Additionally, or alternatively, a UE may receive a CSI-RS, determine a precoding matrix using the CSI-RS and neural network, and transmit an indication of the pre-coding matrix to a base station.

Abstract: Certain aspects of the present disclosure provide techniques for channel quality indictor (CQI) reporting with precoding matrix indicator (PMI) frequency domain (FD) units. A user equipment (UE) may configured with a CSI reporting configuration. CQI and PMI may be configured with different FD unit sizes. The UE may determine which PMI FD units to use for calculating corresponding CQI FD units. PMI and CQI FD units may not be aligned. The UE may determine which PMI FD units to use for calculating CQI based on the alignment. PMI and CQI FD units may be configured using a separate bitmaps, a bitmap and ratio of the FD unit sizes, or a single bitmap. PMI and/or CQI FD units may start from a lowest FD unit index in the system bandwidth, or the lowest FD unit index within a configured bandwidth part (BWP).

Abstract: Certain aspects of the present disclosure provide techniques for allocating channel state information (CSI) processing unit (CPU) for user equipment (UE) initiated CSI. For example, the UE may receive an indication from a network entity (e.g., a base station or gNB) configuring the UE with a number of one or more CPUs allowed to be occupied for UE-initiated CSI feedback. The UE uses the at least one of the CPUs to calculate UE-initiated CSI feedback. The UE transmits at least one report including the UE-initiated CSI feedback if one or more conditions are met, such as when a mismatch between a CSI metric for a scheduled physical downlink shared channel (PDSCH) and a CSI metric calculated as part of the UE-initiated CSI feedback is equal to or exceeding a threshold value.