Abstract: Certain aspects of the present disclosure provide techniques for channel estimation for two-stage sidelink control using sidelink data channel demodulation reference signals (DMRS). A user equipment (UE) can transmit DMRS for the sidelink data channel. The UE may transmit the second stage of the sidelink control using antenna ports or a precoder used for the sidelink data channel. The receiving device may receive the DMRS, estimate the channel, and demodulate the second stage of the sidelink control based on the estimated channel. The receiving device may flexibly determine the DMRS to use for the estimation and demodulation.

Abstract: Certain aspects of the present disclosure provide techniques for unlicensed channel occupancy time sharing based on received signal strength. A method that may be performed by a first user equipment (UE) includes receiving a first transmission from a second UE, the first transmission indicating the second UE has acquired a frequency band for a channel occupancy time (COT). The method may also include transmitting a signal within the frequency band during the COT in response to a signal strength of the first transmission as received by the first UE being greater than at least one threshold.

Abstract: Certain aspects of the present disclosure provide techniques for enhanced feedback transmission for sidelink communication in unlicensed spectrum.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may determine, for a device-to-device communication with another UE, a modulation and coding scheme (MCS) configuration, of a set of MCS configurations, based at least in part on at least one of a transmission mode, a packet characteristic, a mobility state of the UE, a capability of the UE, a transmission mode of the device-to-device communication, a received indication from the other UE, or a combination thereof. The UE may transmit, to the other UE, data using an MCS selected based at least in part on the MCS configuration. Numerous other aspects are provided.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may receive a first set of synchronization signals from a first synchronization source and may receive a second set synchronization signals from a second synchronization source, where the UE determines a first priority for the first synchronization source based on a first identification (ID) associated with the first set of synchronization signals and a second priority for the second synchronization source based on a second ID associated with the second set of synchronization signals. Accordingly, the UE may then select the first synchronization source or the second synchronization source based on which synchronization source has a higher priority and communicate with the selected synchronization source (e.g., via sidelink communications).

Abstract: Certain aspects of the present disclosure provide a method for wireless communications by a transmitter UE. The method generally includes transmitting data to at least one receiver UE in an unlicensed spectrum used for sidelink communication, determining if a resource in a slot is available for the at least one receiver UE to provide acknowledgment feedback for the data transmission, and transmitting a reservation signal in the slot if the resource is determined to be available.

Abstract: Methods, systems, and devices for sidelink wireless communications are described in which a user equipment (UE), such as a vehicle UE, that supports full-duplex communications may transmit a sidelink control channel during a set of time resources including scheduling information for a subsequent transmission by the UE via a first set of resources. The UE may receive a sidelink control channel during the set of time resources from a second UE that may support full-duplex communications or half-duplex communications. The sidelink control channel may include scheduling information for a subsequent transmission via a second set of time-frequency resources that at least partially overlaps with the first set of time-frequency resources. The first UE may determine that a collision will occur and may perform a resource selection procedure or may transmit a request for the second device to perform the resource selection procedure.

Abstract: Certain aspects of the present disclosure provide techniques for sidelink communications in an unlicensed spectrum. A method that may be performed by a user equipment (UE) includes measuring, starting at least at a start time of a time interval, a frequency band to determine whether the frequency band is idle, the time interval including a plurality of time periods. While measuring the frequency band, decoding, by the UE, any signals received on the frequency band to determine if a clear-to-send (CTS) signal is received over the frequency band.

Abstract: Certain aspects of the present disclosure provide techniques for slot format for sidelink communication. A method that may be performed by a user equipment (UE) includes refraining from transmitting during a gap portion of a first symbol in time of a sidelink transmission, wherein the first symbol comprises the gap portion and a signal portion; transmitting a signal during the signal portion of the first symbol; and transmitting a data signal of the sidelink transmission in at least one second symbol subsequent in time to the first symbol in the sidelink transmission.

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, a discontinuous reception (DRX) configuration to be used by the UE for cellular communication with the base station, wherein the DRX configuration indicates a DRX cycle that includes an active time during which the UE is to monitor a physical downlink control channel (PDCCH) and an inactive time during which the UE is to refrain from monitoring the PDCCH; identify a time window for sidelink communication with another UE based at least in part on the DRX configuration; and communicate using one or more sidelink resources in the identified time window. Numerous other aspects are provided.

Abstract: Disclosed are techniques for wireless positioning. In an aspect, a user equipment (UE) may determine a set of one or more parameters for sidelink ranging sessions among session participants comprising a session initiator and at least one session responder, wherein the set of one or more parameters comprises: a first parameter indicating a first duration of time that a sidelink ranging session initiator allocates to receive, from a session responder, a response to a session request; and a second parameter indicating a second duration of time that a session responder allocates to receive a session confirmation from a session initiator after issuing, to the session initiator, a response to a session request. The UE may establish a sidelink ranging session according to the set of one or more parameters.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a wireless communication device may receive, from a base station, information associated with training or configuring an assisting device to provide assistance for a unicast link of a user equipment (UE). The wireless communication device may train the assisting device based at least in part on the information associated with the training or configuring the assisting device. Numerous other aspects are described.

Abstract: Certain aspects of the present disclosure provide techniques for carrier selection for sidelink communications in an unlicensed spectrum. A method that may be performed by a first sidelink user equipment (UE) includes determining one or more carriers, from a set of configured carriers, in an unlicensed spectrum to use for communicating with a second sidelink UE and communicating with the second sidelink UE using the determined one or more carriers.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE), may receive, at a processing layer of the UE, sets of discontinuous reception (DRX) cycle parameters from a corresponding set of applications at an application layer of the UE. The UE may determine, based on the sets of DRX parameters, a common DRX cycle to satisfy each of the sets of applications. The UE may transmit the common DRX cycle to one or more layers in the user plane protocol stack of the UE. A base station may also receive a request, from the UE, for a set of DRX cycle parameters that satisfies the common DRX cycle of the UE. The base station may transmit an indication of the set of DRX parameters, and receive, from the UE, a confirmation of a DRX cycle associated with the set of DRX cycle parameters.

Abstract: Disclosed are techniques for wireless communication. In an aspect, a transmitter user equipment (UE) determines a first zone identifier (ID) corresponding to a first zone in which the transmitter UE is located, determines a distance threshold based on a distance requirement of an application associated with the transmitter UE, determines a second zone ID based on the first zone ID, the distance threshold, a size of the first zone, or any combination thereof, and transmits the second zone ID and the distance threshold to one or more receiver UEs. In an aspect, the receiver UE receives the second zone ID and the distance threshold, determines a distance between the receiver UE and the transmitter UE based on the second zone ID and a location of the receiver UE, and transmits, based on the distance being less than the distance threshold, a feedback message to the transmitter UE.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a receiver user equipment (UE) may receive at least one control communication that includes a first part and a second part. The UE may determine an authenticity status of the at least one control communication based at least in part on at least one of a common security key corresponding to the first part or a private security key corresponding to the second part. The UE may perform a wireless communication task based at least in part on the authenticity status of the at least one control communication. 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 transmit, to another UE, a positioning request associated with a procedure for determining a position of the UE, wherein the positioning request comprises a sidelink communication between a first sidelink location management component (S-LMC) of the UE and a second S-LMC of the other UE, wherein the first S-LMC and the second S-LMC comprise sub-functions associated with a vehicle-to-everything protocol layer; and receive a positioning report associated with the procedure for determining the position of the UE, wherein the positioning report comprises an indication of the position of the UE based at least in part on a determination by a sidelink location management function. Numerous other aspects are provided.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may transmit, to a node, a request for a security key for sidelink connectionless groupcast communication that is performed without a radio resource control connection between UEs. The request may indicate a distance from the UE for using the security key. The UE may receive, from the node, information that indicates the security key. Numerous other aspects are described.

Abstract: This disclosure provides systems, methods, and devices for wireless communication that support hybrid systems sidelink (SL) operations. In a first aspect, an apparatus obtains a resource reservation for a subsequent transmission over an SL, the reservation of a resource in a resource pool, and the resource spanning at least one sub-channel of a plurality of sub-channels. The apparatus further transmits an indication of the resource reservation to at least one other UE, where the UE is of a first type and the at least one other UE is of a second type. Other aspects and features are also claimed and described.

Abstract: Certain aspects of the present disclosure provide techniques for reconfigurable intelligent surface-based interference cancellation. A method that may be performed by a network entity generally includes determining to perform interference cancellation with a reconfigurable intelligent surface (RIS) for interference that will occur at a first wireless node based at least in part on one or more criteria, wherein the interference includes an interfering signal that will be transmitted by a second wireless node; and performing the interference cancellation with reflections from the RIS in response to the determination.