Abstract: Methods, systems, and devices for wireless communications are described. In some systems, a user equipment (UE) may determine a set of groups of layers relating to a set of transport blocks (TBs) or a set of code division multiplexing (CDM) groups. The UE may group the layers such that the layers in each group have a minimal difference in signal-to-interference-plus-noise ratio (SINR) between the layers. The UE may select a different demodulation reference signal (DMRS) configuration for each of the set of groups of layers based on maximizing a communication efficiency metric for each group of layers. The UE may transmit an indication of the selected DMRS configurations for each group of layers to a base station via a field in a report. The base station may accordingly determine a DMRS configuration for each group of layers based on the DMRS configurations indicated by the UE.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may transmit an indication associated with phase noise characteristics of the UE. The UE may receive an indication of pilot allocation sizes, for different data modulation and coding schemes (MCSs) for communications, of frequency-domain contiguous pilots for phase noise mitigation based at least in part on the indication associated with the phase noise characteristics of the UE. 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 one or more reference signals associated with a downlink communication. The UE may transmit an indication of a preferred demodulation reference signal (DMRS) configuration to be used for the downlink communication, the preferred DMRS configuration based at least in part on the one or more reference signals and a transmission mode associated with the preferred DMRS configuration. Numerous other aspects are described.

Abstract: Disclosed are techniques related to wireless communication system in which multi-level encoded modulation (MLCM) is applied to non-coherent communication. In the proposed techniques, a small fraction of differential phase rotations or bits participating in differential symbol coding are protected with strong codes while other complementary differential phase rotations or bits are protected with weaker codes. Compared to conventional non-coherent communication techniques in which a uniform protection is applied to any fraction of differential phase rotation or any bit of a differential symbol, the proposed MLCM approach enables more spectrally efficient scheme.

Abstract: Methods, systems, and devices for wireless communications are described for estimating one or more environmental factors at a first user equipment (UE). The one or more environmental factors may be based on estimates of a Doppler spread and a power delay profile (PDP) taken over a set of subsets of a time period, based on multiple signals received from a second UE or a base station over the time period. The first UE may estimate the Doppler spread and PDP for a channel over each of the set of subsets of the time period, and may combine the Doppler spread over the set of subsets and combine the PDP over the set of subsets. The first UE may use the combined Doppler spread and the combined PDP to determine one or more communication parameters for the channel.

Abstract: In one aspect, performing, by a wireless communication device, a non-coherent encoding operation on first data to generate a first transmission, wherein the non-coherent encoding operation encodes data independent of channel state information (CSI); and transmitting, by the wireless communication device, the first transmission, wherein the first transmission is non-coherently encoded. In another aspect, receiving, by a wireless communication device, a first transmission, wherein the first transmission is non-coherently encoded independent of channel state information (CSI); and performing, by the wireless communication device, a non-coherent decoding operation on the first transmission to decode the first transmission. Other aspects and features are also claimed and described.

Abstract: Certain aspects of the present disclosure relate to wireless communications, and more particularly, to techniques for phase noise (PN) mitigation on multiple component carriers (CCs). A method that may be performed by a user equipment (UE) includes estimating impairments (e.g., common phase error (CPE) and/or inter-carrier interference (ICI)) caused by PN for only a first CC configured for the UE, wherein the first CC is configured with pilots for PN mitigation and mitigating the PN on each CC for all CCs configured for the UE based, at least in part, on the estimated impairments for the first CC.

Abstract: Aspects of disclosure relate to a UE reporting to a gNB time delays and phases of pilot signals received via multiple transmission paths in order for the gNB to pre-equalize a future transmission to the UE. The UE determines a first time delay for receiving a first pilot signal from a gNB via a first path, determines a second time delay for receiving a second pilot signal from the gNB via a second path, and generates a report based on the first time delay and the second time delay. The UE then sends the report to the gNB and receives a multi-TRP signal from the gNB via the first path and the second path, wherein the multi-TRP signal is pre-equalized for transmission based on the report to at least have a same time delay as a shorter one of the first time delay or the second time delay.

Abstract: An apparatus for wireless communication includes a transmitter and a receiver. The receiver is configured to receive a first code block (CB) that is associated with a code block group (CBG) and that is included in a transport block (TB). The receiver is further configured to receive a second CB that is associated with the CBG and that is included in the TB. The first CB is distinct from the second CB. The second CB includes at least a first bit that is associated with the first CB.

Abstract: Methods, systems, and devices for wireless communications are described. Generally, the described techniques provide for flexible selection of a type of mapping to use for mapping code blocks to a set of resources for transmission. A user equipment (UE) may transmit assistance information to a base station to assist the base station in selecting from a set of mapping types available for code block mapping. The UE may then receive, from the base station, an indication of a selected mapping type for code block mapping based on the assistance information. The assistance information may include a recommendation of a mapping type or a metric of a channel that the base station may use to select the mapping type. Because the mapping type may be selected dynamically (e.g., “on the fly”), the UE and the base station may be able to adaptively exploit different types of diversity.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a communication device may classify a set of packets of streaming video content based at least in part on one or more video characteristics; assign the set of packets to a plurality of transport blocks based at least in part on classifying the set of packets, wherein a first transport block is associated with a first set of values for a set of communication parameters and a second transport block is associated with a second set of values for the set of communication parameters, and wherein the set of communication parameters is associated with a layer mapping technique; and provide the plurality of transport blocks for transmission based at least in part on assigning the set of packets to the plurality of transport blocks. Numerous other aspects are provided.

Abstract: Methods, systems, and devices for wireless communications are described. A base station may determine the subcarrier spacing and carrier frequency used by a user equipment (UE) for communicating with the base station. The base station may select a sounding reference signal (SRS) configuration for the UE that is based on the subcarrier spacing and carrier frequency used by the UE. The SRS configuration may define the temporal spacing between repetitions of the SRS. The base station may indicate the SRS configuration to the UE so that the UE transmits repetitions of the SRS according to the SRS configuration. The base station may measure the SRS repetitions from the UE to determine the Doppler frequency for the uplink channel. The base station may use the uplink Doppler frequency to select a demodulation reference signal (DMRS) configuration for the UE.

Abstract: Methods, systems, and devices for wireless communications are described that support a single carrier multi-level coding (MLC) amplitude phase shift keying (APSK) modulated waveform. For example, a user equipment (UE) capable to communicate using MLC APSK modulated waveforms may transmit a channel state information (CSI) report, including a recommendation for a waveform configuration, to a base station. The base station may receive the CSI report and may transmit a configuration message to the UE, which may configure the UE with a set of waveform parameters associated with MLC APSK modulation. The UE may receive the configuration message and may communicate with the base station using MLC APSK modulated waveforms and based on the set of waveform parameters, which may reduce phase noise and provide lower peak average power ratio (PAPR) signaling.

Abstract: A base station may configure a Doppler tracking sounding reference signal (SRS) resource set with different time gaps between SRS resources of the Doppler tracking SRS resource set. However, factors influencing an optimal time gap for uplink Doppler parameter estimation may change over time and may depend on a Doppler parameter to be estimated. Therefore, parameters of an aperiodic Doppler tracking SRS resource set configuration may become suboptimal for estimating uplink Doppler parameters. Some techniques and apparatuses described herein enable dynamic parameter adaptation for aperiodic Doppler tracking SRS resource sets. The base station may dynamically adapt one or more parameters for an aperiodic Doppler tracking SRS resource set to modify a time gap and/or a number of resources or symbols to be transmitted for an aperiodic Doppler tracking SRS resource set. The base station may transmit downlink control information that indicates the one or more parameters.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) receives control signaling from the base station indicating a set of transmission mode indicators or transmission mode options and a set of demodulation reference signal (DMRS) configurations for every transmission mode from a set of transmission modes. The base station transmits additional control signaling to dynamically indicate a transmission mode or a combination of transmission mode indicators and DMRS configuration parameters to signal the transmission mode and one or more associated DMRS configurations. The UE identifies a DMRS configuration and a transmission mode based on the additional control signaling. The UE receives one or more DMRSs from multiple transmission reception points (TRPs) based on the joint/disjoint DMRS and transmission mode signaling. The UE receives one or more data messages from the TRPs based on the transmission mode indication and based on the received DMRSs.

Abstract: Methods, systems, and devices for wireless communications are described. A base station communicates with a UE via transmission reception points (TRPs). A UE receives, from a base station, control signaling identifying a set of demodulation reference signal (DMRS) configurations. The UE receives, from the base station, control signaling activating a first DMRS configuration and a second DMRS configuration. The UE receives an indication for the UE to use a first transmission mode of a set of transmission modes to communicate with multiple TRPs of the base station. The UE selects at least one of the first DMRS configuration or the second DMRS configuration based on the indicated first transmission mode and a pre-defined logical association. The UE then receives DMRS signals from the TRPs of the base station, according to the selected at least one of the first DMRS configuration or the second DMRS configuration.

Abstract: Disclosed are techniques for wireless communication. In an aspect, a base station receives one or more signals indicative of a downlink compensation capability (e.g., an in-band capability to compensate for non-linear distortion, or an out-of-band capability to compensate for other FDM'd signal(s) to other UE(s), etc.) of at least one UE. The base station determines a set of downlink transmission requirements based on the downlink compensation capability of the at least one UE, and transmits data to the at least one UE in accordance with the set of downlink transmission requirements.

Abstract: A first wireless device may receive, from a second wireless device, a transmission associated with an MLC scheme. The MLC scheme may include a plurality of bits with at least one first bit corresponding to a first level of the plurality of bits and at least one second bit corresponding to a second level of the plurality of bits. The at least one first bit may be coded with a first level of complexity, but the at least one second bit may be coded with either the first level of complexity or a second level of complexity, where the first level of complexity may be a higher level of complexity than the second level of complexity. The first wireless device may decode the at least one first bit and the at least one second bit using a decoder having a corresponding level of complexity.

Abstract: Aspects described herein relate to converting, by applying a non-linear function, a symbol indicating first data into an analog signal for transmitting to a network node, wherein applying the non-linear function indicates second data, separate from first data, and transmitting the analog signal to the network node. Additional aspects relate to receiving an analog signal from a user equipment (UE), and estimating a non-linear function applied to the analog signal in converting a symbol indicating first data into the analog signal, wherein estimating the non-linear function indicates second data, separate from first data.

Abstract: Methods, systems, and devices for wireless communications are described that support a single carrier multi-level coding (MLC) amplitude phase shift keying (APSK) modulated waveform. For example, a user equipment (UE) capable to communicate using MLC APSK modulated waveforms may transmit a channel state information (CSI) report, including a recommendation for a waveform configuration, to a base station. The base station may receive the CSI report and may transmit a configuration message to the UE, which may configure the UE with a set of waveform parameters associated with MLC APSK modulation. The UE may receive the configuration message and may communicate with the base station using MLC APSK modulated waveforms and based on the set of waveform parameters, which may reduce phase noise and provide lower peak average power ratio (PAPR) signaling.