Abstract: This disclosure provides systems, methods and apparatus for wireless communications that support fallback from a 2-step to a 4-step random access procedures. A user equipment (UE) may establish a connection with a base station using a random access procedure. The random access procedure may be a 2-step random access procedure and reduce a number of handover exchange messages. The 2-step random access procedure may include the UE transmitting, to the base station, a first random access message including a preamble and a payload. In some implementations, the base station may receive the preamble but fail to receive or decode the payload. The random access procedure may utilize the received preamble information instead of performing retransmission of the first random access message. The base station may transmit a second random access message to the UE indicating, explicitly or implicitly, a fallback to a 4-step random access procedure for connection establishment.

Abstract: Disclosed is a method of wireless communication. The method is performed at a user equipment (UE). The method comprises receiving, from a network entity, downlink control information (DCI) for a downlink transmission, wherein the downlink transmission is based on a rate-splitting multiple access scheme, and wherein the downlink transmission comprises a common stream, a demodulation reference signal (DM-RS) for the common stream, a private stream and a DM-RS for the private stream, determining, based on the DCI, a DM-RS configuration for the DM-RS for the common stream and for the DM-RS for the private stream, and receiving, based on the DM-RS configuration, the downlink transmission.

Abstract: A user equipment may be configured to perform active interference cancellation for random-access channel. In some aspects, the user equipment may receive, from a base station, physical layer random-access channel (PRACH) configuration information including one or more active interference cancellation (AIC) parameters for applying AIC to a PRACH message to the base station. Further, the user equipment may transmit, to the base station, the PRACH message with one or more AIC subcarriers based on the one or more AIC parameters.

Abstract: Certain aspects of the present disclosure provide a method for wireless communications by a transmitter UE. The method generally includes receiving, from a network entity, a downlink control information (DCI) allocating resources in an unlicensed frequency band for multiple physical sidelink shared channel (PSSCH) transmissions to at least one receiver UE across transmission time intervals (TTIs), performing a listen-before-talk (LBT) channel access procedure in the TTIs, and transmitting at least one LBT report to the network entity on a physical uplink control channel (PUCCH) resource that occurs before another PUCCH resource used for transmitting acknowledgment feedback for the PSSCH transmissions.

Abstract: Channel occupancy time (COT) aware sensing and resource selection for new radio-unlicensed (NR-U) sidelink operations is disclosed. A first sidelink user equipment (UE) determines a sensing window or resource selection window (RSW) based on a projected listen-before-talk (LBT) completion time. The UE may sense for a subset of sideline resources within the RSW and COT-SI from a neighboring sidelink UE including identification of a COT initiated by the neighboring UE and one or more parameters associated with the COT. The UE may identify in-COT resources of located within the COT and out-of-COT resources located outside of the COT and then randomly select a set of transmission resources from the in-COT and out-of-COT resources. The UE may then transmit to a second UE using the set of transmission resources.

Abstract: Methods, systems, and devices for wireless communications are described. For instance, a user equipment (UE) may receive, from a base station, a first downlink control information message in a downlink control channel, the first downlink control information message scheduling first resources of a downlink shared channel for a second downlink control information message. The UE may identify a first, UE-specific scrambling sequence for the second downlink control information message. The UE may receive, from the base station, the second downlink control information message based on the first scrambling sequence, the second downlink control information message scheduling second resources of the downlink shared channel for a data message. The UE may receive, from the base station, the data message in the second resources scheduled by the second downlink control information message.

Abstract: Some aspects described herein relate transmitting, to a receiving UE, a sidelink control information (SCI) that schedules multiple transport blocks (TBs) of shared channel communications in multiple time divisions, and transmitting, to the receiving UE and based on the SCI, the multiple TBs of shared channel communications in the multiple time divisions. Other aspects relate to receiving, from a transmitting UE, a SCI that schedules multiple TBs of shared channel communications in multiple time divisions, and receiving, from the transmitting UE and based on the SCI, the multiple TBs of shared channel communications in the multiple time divisions. Additional aspects relate to configuring the UEs in this regard.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) and a base station may communicate in an unlicensed spectrum (e.g., a shared radio frequency spectrum band). As such, the UE may determine a codebook size for transmitting hybrid access request (HARQ) acknowledgement (ACK) feedback with respect to the unlicensed spectrum. Accordingly, the UE may base the HARQ ACK codebook size on a number of HARQ processes with which the UE has been configured. Additionally or alternatively, the UE may base the HARQ ACK codebook size on a number and/or duration of downlink channel monitoring occasions indicated by the base station. In some cases, the UE may base the HARQ ACK codebook size on a combination of the techniques described herein.

Abstract: Methods, systems, and devices for wireless communications are described. A communication device, which may be otherwise known as user equipment (UE) may receive a downlink control information (DCI) on a physical downlink control channel (PDCCH). The DCI may include one or more of an indication of a set of transmission configuration indicator (TCI) states related to a physical downlink shared channel (PDSCH), one or more receive beams associated with the set of TCI states, or a physical downlink shared channel (PDSCH) scheme. The UE may decode the DCI and may determine a temporal period associated with the indication of the set of TCI states. The UE may receive, based on the temporal period, the PDSCH according to one or more of the set of TCI states, the one or more receive beams associated with the set of TCI states, the PDSCH scheme, or one or more default receive beams.

Abstract: Disclosed are techniques for wireless sensing and/or positioning. In an aspect, a base station (BS) may define a resource set comprising a plurality of phase-coherent positioning resources, the phase-coherent positioning resources comprising phase-coherent positioning reference signal (PRS) resources, phase-coherent sounding reference signal (SRS) resources, or a combination thereof. The BS may configure a user equipment (UE) with the resource set. The BS may use the plurality of phase-coherent positioning resources, including transmitting phase-coherent PRS signals using the phase-coherent PRS resources, receiving phase-coherent SRS signals using the phase-coherent SRS resources, or a combination thereof.

Abstract: Systems and method for configuring and providing discontinuous reception (DRX) operations in sidelink (SL) mode 1 and mode 2 are disclosed. A first user equipment (UE) may operate in DRX communications with a second UE over a SL while concurrently maintaining DRX communications with a base station. In some embodiments, DRX operations may include the first UE monitoring for either one or both of transmissions in a downlink from a base station and in the SL from the second UE during an active period of a DRX cycle of the DRX configuration. In embodiments, the UE may extend the active period associated with the DRX cycle when control information from either the base station or the second UE is received. Other aspects and features are also claimed and described.

Abstract: Methods, systems, and devices for wireless communications are described. In some wireless communications systems, a user equipment (UE) may receive, from a base station, downlink control information (DCI) that activates periodic channel state information (CSI) reporting via uplink shared channel transmissions (e.g., via physical uplink shared channel (PUSCH) transmissions). The UE may then identify a trigger condition that triggers a transmission of both a first instance of a CSI report and a second instance of the CSI report within a period of the periodic CSI reporting. Based on the satisfaction of the trigger condition, the UE may transmit the first instance of the CSI report via a first uplink shared channel transmission and the second instance of the CSI report via a second uplink shared channel transmission, where both uplink channel transmissions are within the period of the periodic CSI reporting.

Abstract: Methods, systems, and devices for wireless communication are described. A user equipment (UE) may transmit, to a base station, a capability report that includes an indication of a maximum number of reference signal resources within a transmission time interval (TTI) for which the UE supports channel state information (CSI) reporting. The maximum number of reference signal resources may be based on a capability for supporting joint CSI reporting for both a downlink and an uplink. The UE may receive, from the base station, a report configuration in response to the capability report. Subsequently, the base station may transmit reference signals to the UE, which the UE may use to determine CSI for both the downlink and the uplink. The UE may then transmit, to the base station, a CSI report including the CSI for both the downlink and the uplink, in accordance with the report configuration.

Abstract: Methods, systems, and devices for wireless communications are described. A UE may determine resource amounts for transmitting feedback codebook for two different service types based on satisfaction of a multiplexing condition by overlapping resource schedules. The codebooks may be encoded according to different coding rates to generate encoded feedback codebooks. The encoded codebooks may be mapped to transmission resources according to codebook payload sizes, encoding rates, and available resources and transmitted according to the mapping.

Abstract: Methods, systems, and devices for wireless communications are described. A method for wireless communication at a user equipment (UE) may include: receiving a multicast bandwidth part configuration for multicast communications between a base station and the UE, where the multicast bandwidth part configuration includes a maximum number of multiple-input, multiple-output layers to be used for the multicast communications; establishing a multicast link with the base station for multicast communications; determining to use a reduced number of antennas for multicast reception than the number of antennas used for unicast reception, or determining that the UE is able to decode the multicast communications prior to a remaining portion of the multicast communications; and receiving the multicast communications via the reduced number of antennas, or reducing the radio frequency power prior to completion of a number of repetitions or retransmissions of the multicast communications.

Abstract: A phase tracking reference signal (PT-RS) may be transmitted to enable a receiver to correct phase noise in wireless communication. A UE scheduled for one PDSCH with DMRS ports in two or more DMRS CDM groups that are associated with two TCI states may be configured for PT-RS using two PT-RS ports. Therefore, rather than limiting PT-RS to a single port, the PT-RS may be transmitted to the UE using two PT-RS ports. The apparatus transmits a capability indication for more than one PT-RS port for receiving a downlink shared channel based on a first TCI and a second TCI. The apparatus receives a configuration for a maximum number of downlink PT-RS ports from a base station.

Abstract: Methods, systems, and devices for wireless communications are described. A transmitting device may perform a first transmission to one or more receiving devices, the first transmission associated with a transmission type. The transmitting device may determine a feedback response for the first transmission based on monitoring for feedback messages from the one or more receiving devices in response to the first transmission. The transmitting device may select a contention window size for performing one or more subsequent transmissions based at least in part on the feedback response and the transmission type. The transmitting device may perform the one or more subsequent transmissions in accordance with a clear channel assessment procedure using the selected contention window size.

Abstract: In an embodiment, a wireless node (e.g., UE or BS) receives from a network component (e.g., BS or core network component) a request for a positioning estimate of a UE associated with a specified time. The wireless node performs positioning measurements at a plurality of times, and determines (e.g., via interpolation or extrapolation) the positioning estimate associated with the specified time based on the positioning measurements. The wireless node transmits, to the network component, a report comprising the determined positioning estimate.

Abstract: Certain aspects of the present disclosure provide techniques for synchronization signal block (SSB) patterns with gaps. A method that may be performed by a network entity (e.g., a BS) generally includes determining a synchronization signal block (SSB) pattern that identifies SSB positions for sweeping a set of SSB beams over multiple SSB bursts with gaps between at least some of the SSB positions, wherein the SSB pattern identifies a subset of the set of SSB beams to use per SSB burst. The method generally includes transmitting SSBs over the multiple SSB bursts in accordance with the pattern.

Abstract: Methods, systems, and devices for wireless communications are described. In some examples, a user equipment (UE) may receive a control signal that triggers the UE to transmit one or more SRSs of an SRS resource set, where the SRS resource set spans multiple slots, and to receive configuration information that includes timing information for transmission of the one or more SRSs relative to a timing of receipt of the control signal. Additionally, the described techniques provide for a UE to receive a control signal that indicates an SRS beam management configuration that identifies at least a first SRS resource set and a second SRS resource set that are linked together such that the UE may determine a transmit beam for an SRS resource of the second SRS resource set based on an additional transmit beam for a corresponding SRS resource of the first SRS resource set.