Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may determine one or more demodulation reference signal (DMRS) scrambling sequences using a low peak-to-average power ratio (PAPR) sequence generator, each corresponding to a respective port of one or more ports, the one or more ports being associated with a downlink multiple input multiple output (MIMO) communication, wherein the downlink MIMO communication is a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM)-based communication. The UE may receive the downlink MIMO communication including a DMRS according to an intra-slot DMRS pattern that indicates one or more time domain multiplexed symbols, each being at least partially allocated with at least one DMRS scrambling sequence of the one or more DMRS scrambling sequences. Numerous other aspects are described.

Abstract: Methods, systems, and devices for wireless communications are described. The described techniques support blind common phase error (CPE) and residual carrier frequency offset mitigation. Generally, the described techniques provide for blind CPE mitigation at a receiving device without a phase tracking reference signal (PTRS) associated with less overhead and improved performance as compared to use of a PTRS to mitigate CPE. A receiving device may receive a shared channel message in a scheduled shared channel allocation in accordance with a PTRS configuration that omits a PTRS allocation based on a capability of the receiving device to apply blind CPE mitigation for shared channel receptions. In some examples, with a single DMRS symbol allocation, blind CPE mitigation for each subsequent data symbol of a shared channel message may be based on the blind CPE estimation for the previous symbol, which may enable robust mitigation of a residual carrier frequency offset.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment may transmit a request, for an uplink transmission or a downlink transmission, for data aided phase tracking reference signals (PT-RSs) on multiple layers of a communication link; and communicate the uplink transmission or the downlink transmission based at least in part on the request. Numerous other aspects are provided.

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: This disclosure provides systems, methods, and apparatus, including computer programs encoded on computer-readable media, for determining a constellation configuration for an amplitude phase shift keying (APSK) modulation scheme. The constellation configuration may be based on communication impairment information that is indicative of at least one communication impairment expected to impair a single-carrier waveform communication. Examples of communication impairments may include additive white gaussian noise (AWGN), phase noise, non-linear distortion, or any combination thereof, among other examples. Examples of a constellation configuration may include a quantity of rings in a constellation pattern associated with the APSK modulation scheme, a quantity of constellation points associated the rings, a ring radius associated with one or more rings, a phase offset to one or more rings, and a mapping of data bits to one or more constellation points, among other examples.

Abstract: In a wireless communication system, dynamic changes of a code block (CB) to resource element (RE) mapping type may improve decoding performance in some scenarios. A user equipment may provide an indication of a preferred CB mapping type. A base station may transmit a physical downlink shared channel (PDSCH) based on a first dynamic CB mapping type in one or more slots. A UE may receive the PDSCH and determine a second CB mapping type that is preferred by the UE based on a metric. The UE may transmit an indicator of the second CB mapping type, for example, as a one-bit or two-bit indicator, which may be coupled with a channel state information (CSI) report or signaled in uplink control information (UCI) independently from a CSI report. The base station may consider the indicator when selecting a new dynamic CB mapping type for the UE.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may receive a message from a network entity indicating a first set of configuration parameters for tracking reference signals (TRSs) specific to the UE. The UE may monitor for one or more TRSs according to the first set of configuration parameters and during a first time interval. The UE may receive a layer-1 (L1) signal or a layer-2 (L2) signal from the network entity indicating a second set of configuration parameters for the TRSs specific to the UE that are different from the first set of configuration parameters. The UE may transmit an acknowledgement message to the network entity indicating the UE received the L1 signal or the L2 signal. During a second time interval subsequent to the first time interval, the UE may monitor for additional TRSs according to the second set of configuration parameters.

Abstract: The apparatus may be a UE configured to transmit, to a base station, an indication of a UE capability associated with a contiguous FD pilot; receive, from the base station, an indication of an allocation of one or more frequency sub-bands for a reception of one or more contiguous FD pilots; and receive, from the base station, the one or more contiguous FD pilots via the one or more frequency sub-bands. The apparatus may be a configured to receive, from a UE, an indication of a UE capability associated with a contiguous FD pilot; select one or more frequency sub-bands for a transmission of a contiguous FD pilot; transmit, to the UE, an indication of an allocation of the one or more frequency sub-bands for the transmission of the contiguous FD pilot; and transmit, to the UE, the contiguous FD pilot via the one or more frequency sub-bands.

Abstract: Certain aspects of the present disclosure provide techniques for network assisted selection of UE antenna ports for uplink transmissions. A method for wireless communication by a user equipment (UE) includes transmitting, to a network entity, a plurality of sounding reference signals over a plurality of UE antenna ports. The method further includes receiving, from the network entity, an indication of one or more antenna port indexes associated with one or more preferred antenna ports for uplink transmissions, and transmitting UE uplink transmissions to the network entity using one or more selected antenna ports of the one or more indicated preferred antenna ports.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive, from a network entity, a demodulation reference signal (DMRS) configuration indicating an intra-slot DMRS pattern. The UE may receive, from the network entity, an indication of an inter-slot DMRS pattern. The UE may communicate, with the network entity, a message that is associated with a time domain resource allocation that includes multiple slots, the message including one or more DMRSs in accordance with the intra-slot DMRS pattern and the inter-slot DMRS pattern. Numerous other aspects are provided.

Abstract: Aspects of the techniques and apparatuses described herein provide an intra slot antenna diversity scheme that a user equipment (UE) may use to transmit uplink communications while mitigating antenna imbalance. In an intra slot antenna diversity scheme, a UE transmits an uplink communication by transmitting a first portion of the uplink transmission in a first part of a slot using a first subset of antennas and a second portion of the uplink communication in a second part of the slot using a second subset of antennas. A decision to apply an intra slot antenna diversity scheme may be made by a network node such as a base station. Numerous other aspects are described.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may receive a message from a network entity indicating a first set of configuration parameters for tracking reference signals (TRSs) specific to the UE. The UE may monitor for one or more TRSs according to the first set of configuration parameters and during a first time interval. The UE may receive a layer-1 (L1) signal or a layer-2 (L2) signal from the network entity indicating a second set of configuration parameters for the TRSs specific to the UE that are different from the first set of configuration parameters. The UE may transmit an acknowledgement message to the network entity indicating the UE received the L1 signal or the L2 signal. During a second time interval subsequent to the first time interval, the UE may monitor for additional TRSs according to the second set of configuration parameters.

Abstract: Methods, systems, and devices for wireless communications are described. A transmitting device may operate in a non-linear region of a power amplifier by reporting an indication of power amplifier characteristics and backoff values to a receiving device. The indication of the power amplifier characteristics and the backoff values may be based on power amplifier operation in the non-linear region of power amplifier characteristic curves. The transmitting device may transmit, to the receiving device, signaling using a single carrier waveform at a transmission power in the non-linear region of the power amplifier characteristic curves based on the indication. The receiving device may receive the signaling and use the power amplifier characteristics and the backoff values to perform debiasing and nonlinearity corrections to recover the original signaling.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may support synchronization signal block (SSB) coverage extension for a sub-terahertz (sub-THz) band. The UE may monitor for multiple primary synchronization signals (PSSs) in a first instance of an SSB, a number of PSSs determined by the base station based on a periodicity of the SSB. The UE may combine the PSSs and determine a frequency offset for the SSB. The UE may monitor for additional instances of the SSB in accordance with the frequency offset. In some examples, the UE may monitor for one or more secondary synchronization signals (SSSs) in the first and additional instances of the SSB and combine the SSSs. In addition, the UE may monitor for a physical broadcast channel (PBCH) in the first and additional instances of the SSB, and decode the PBCH using log-likelihood ratio (LLR) combining.

Abstract: In a wireless communication system, dynamic changes of a code block (CB) to resource element (RE) mapping type may improve decoding performance in some scenarios. Dynamic CB mapping may impact calculation of channel state information (CSI) metrics. A base station may transmit a physical downlink shared channel (PDSCH) based on a first dynamic CB mapping type in one or more slots. The base station may transmit a CSI reference signal (CSI-RS). A UE may receive the PDSCH and CSI-RS and calculate a channel quality indicator (CQI) and rank indicator (RI) based on the CRS assuming a second dynamic CB mapping type. The UE may transmit a CSI report including the CQI and the RI to the base station, which may assume the same second dynamic CB mapping type for the CQI and the RI.

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: Aspects of the techniques and apparatuses described herein provide an intra slot antenna diversity scheme that a user equipment (UE) may use to transmit uplink communications while mitigating antenna imbalance. In an intra slot antenna diversity scheme, a UE transmits an uplink communication by transmitting a first portion of the uplink transmission in a first part of a slot using a first subset of antennas and a second portion of the uplink communication in a second part of the slot using a second subset of antennas. A decision to apply an intra slot antenna diversity scheme may be made by a network node such as a base station. Numerous other aspects are described.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a receiving device may receive, via a multi-layer communication link, an indication of one or more parameters for grouping code blocks (CBs) of a transport block (TB) into CB groups (CBGs). The receiving device may receive the TB having multiple CBs mapped to resources of the TB in a frequency first per layer (FFPL) mapping configuration, wherein the CBGs include a CB received on a first layer and a CB received on a second layer of the multi-layer communication link. The receiving device may transmit hybrid automatic repeat request (HARQ)-acknowledgment (ACK) feedback for the CBGs based at least in part on the grouping of the CBs. Numerous other aspects are described.

Abstract: Aspects are provided which allow for a base station to transmit code blocks according to a frequency first per layer (FFPL) mapping, and for a UE to decode received code blocks according to the FFPL mapping. The base station maps a plurality of code blocks to multiple layers, where each of the code blocks is mapped to a plurality of resource elements initially by frequency and subsequently by time on only a single layer of the multiple layers. The base station then transmits data including the code blocks to a UE. Afterwards, the UE receives the data including the mapped code blocks in multiple layers from the base station, and the UE decodes the code blocks based on the mapping. Thus, improvements in link efficiency, reliability, and reduced power consumption compared to frequency first (FF) mapping approaches may be achieved.

Abstract: Certain aspects of the present disclosure provide a method for wireless communication by a user equipment (UE). The UE receives, from a network entity, signaling dynamically enabling a code block group (CBG) configuration. The UE processes downlink (DL) transport blocks (TBs) including a number of CBGs, in accordance with the CBG configuration. The UE transmits, to the network entity, CBG-level acknowledgment information indicating results of the processing.