Abstract: Methods, systems, and devices for wireless communications are described. A first user equipment (UE) may establish a unicast connection over a sidelink communications with a second UE. To establish the unicast connection over the sidelink, the first UE may transmit a request message (e.g., a first message) to the second UE, and the second UE may transmit a response message (e.g., a second message) to the first UE accepting the request. The unicast connection over the sidelink may then be established between the first UE and the second UE, and user data may then be transmitted over the sidelink on the established unicast connection. Additionally, the first UE may transmit a connection complete message (e.g., a third message) to the second UE indicating that the unicast connection has been established. The request message, the response message, and the connection complete message may be radio resource control (RRC) messages.

Abstract: Methods, systems, and devices for wireless communication are described. A first user equipment (UE) may monitor various sensors to obtain data associated with a user of the first UE, and may determine that the user is in a vulnerable state based on monitoring these sensors. The vulnerable state of the user may include an inebriated state, a distracted state, an impaired state, or a disabled state, among other examples. After detecting the vulnerable state of the user, the first UE may transmit a public safety message (PSM) to other devices in the area. Upon receiving the PSM from the UE, a network entity may use positioning information to identify other UEs within a threshold distance of the first UE, and may transmit an alert message to these UEs. The techniques described herein may reduce the probability of nearby pedestrians or vehicles colliding with the user.

Abstract: Methods, systems, and devices for wireless communication are described. A user equipment (UE) may receive a message indicating that a base station supports allocating resources for sidelink communications using a first radio access technology (RAT) and a second RAT that is different from the first RAT. The UE may transmit a sidelink information message to the base station using the first RAT that indicates that sidelink communications are to be performed using either the second RAT or both the first RAT and the second RAT. The UE may receive a configuration message from the base station that comprises an identifier for the sidelink communications and an indication of available sidelink resources. The UE may transmit, based at least in part on the configuration message, a request for resources within the available sidelink resources, the request indicating the identifier and a buffer status report (BSR).

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: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may configure sidelink control information (SCI) to indicate a plurality of sidelink transmission opportunities that are to be reserved for the UE. The UE may transmit the SCI to one or more other UEs. Numerous other aspects are provided.

Abstract: Methods, systems, and devices for wireless communications are described. A wireless device may receive, from a network entity, a control message for a radar reference signal (RRS) configuration associated with the wireless device. The wireless device may set a timing pattern for the RRS based on the control message and one or more timing parameters for the RRS configuration. The wireless device may transmit the RRS according to the timing pattern. The RRS may include one or more cyclic prefix (CP) sub-symbols and one or more RRS sub-symbols. The wireless device may receive one or more reflections of the RRS and may perform one or more processing operations on the one or more reflections of the RRS using a plurality of sampling windows. A quantity of sampling windows may be equal to a quantity of CP sub-symbols.

Abstract: To facilitate coexistence of a first radio access technology (RAT) and a second RAT, methods, apparatuses, and computer program products are provided. An example method of a first wireless device operating based on a RAT includes receiving a sidelink resource reservation from a second wireless device based on a second RAT, the sidelink resource reservation indicating a first set of resources. The example method further includes determining whether to exclude, from a candidate resource set for the first RAT within a sidelink resource pool for the first RAT, resources that overlap with the set of reserved resources for the second RAT. The example method further includes transmitting a sidelink transmission using one or more sidelink transmission resources selected from the candidate resource set in the sidelink resource pool for the first RAT.

Abstract: Aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may determine whether a peer-to-peer (P2P) communication is to be relayed based at least in part on a location of the UE and a range requirement associated with the P2P communication; and transmit the P2P communication, wherein the P2P communication includes an indication of whether the P2P communication is to be relayed. In some aspects, a UE may receive the P2P communication; determine whether to relay the P2P communication based at least in part on the indication and at least one of: a location of the UE, or a UE identifier, included in the P2P communication, that identifies the UE and is associated with a request for the UE to relay the P2P communication; and selectively relay the P2P communication based at least in part on determining whether to relay the P2P communication.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a first user equipment (UE) may receive, from one or more additional UEs, one or more indicators corresponding to one or more resource reservations. Accordingly, the UE may transmit data, to a second UE, on a sidelink channel, with at least one resource reservation, of the one or more resource reservations, indicated within a control element transmitted with the data. For example, the control element may include a list or a bitmap indicating the at least one resource reservation. Numerous other aspects are described.

Abstract: Wireless communication devices are adapted to facilitate power conservation and sidelink communications. According to one example, a wireless communication device can transmit a reservation signal to reserve one or more sidelink resources for use by another device, and receive a sidelink transmission from the other device on at least a portion of the one or more reserved sidelink resources. According to another example, a wireless communication device can detect a reservation signal from another device, where the reservation signal is configured to reserve one or more sidelink resources, and transmit a sidelink transmission on at least a portion of the one or more of the sidelink resources reserved by the other device. Other aspects, embodiments, and features are also included.

Abstract: Some aspects described herein relate to detecting, for a first vehicle, presence of an obstacle in a driving path of a vehicle, determining, for a second vehicle, a sight stopping distance between the second vehicle and the obstacle, and transmitting, to the second vehicle and where the sight stopping distance is within a threshold, a message including a notification of the obstacle.

Abstract: Methods, systems, and devices for wireless communications are described to support transmitting a network coded combined message to a second wireless device that may have missed at least one sidelink message included in another network coded combined message. A first wireless device may identify that the sidelink messages are configured for network coding based on information associated with the sidelink messages. Control information associated with the network coded combined message may indicate that the network coded message is a network coded combined retransmission of the sidelink messages, and may further include information identifying the sidelink messages and devices that transmitted the sidelink messages. The first wireless device may combine the sidelink messages into the network coded combined message and may transmit the control information and the associated network coded combined sidelink message to the second wireless device, which may support decoding of one or more missed sidelink messages.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may transmit compressed bitmap(s) to indicate preferred or non-preferred sidelink resources. A first UE may monitor a set of sidelink resources including a set of slots and subchannels for the slots and determine which resources are available for communications for a second UE. In some examples, the first UE may generate a bitmap indicating which slots have at least one subchannel that is unavailable, and, for each slot having at least one subchannel that is unavailable, a bitmap indicating which subchannels are unavailable for that slot. The first UE may transmit the bitmaps to the second UE. In some examples, the first UE may generate a bitmap indicating which slots have at least one subchannel that is available, and, for each slot having at least one subchannel that is available, a bitmap indicating which subchannels are available.

Abstract: Certain aspects of the present disclosure provide techniques for wireless in-vehicle networking. A method that may be performed by a device in a vehicle includes wirelessly transmitting a data packet directly via a first device-to-device (D2D) communication link to another device in the vehicle; monitoring for an acknowledgment (ACK) of the data packet; deciding whether to retransmit the data packet to the other device, based on the monitoring; and wirelessly transmitting the data packet to a transmission relay, wherein an intended destination of the data packet is the other device, wherein the monitoring for the ACK comprises monitoring for a first ACK from the other device and a second ACK from the transmission relay.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may determine whether sufficient resources are available to perform a transmission in a current slot. The UE may transmit the transmission in the current slot, transmit an early reservation signal for a future resource, or determine whether sufficient resources are available to perform the transmission in a subsequent slot based at least in part on a probability-based determination and based at least in part on whether sufficient resources are available to perform the transmission in the current slot. Numerous other aspects are provided.

Abstract: This disclosure provides systems, devices, apparatus, and methods, including computer programs encoded on storage media, for assisted connectivity techniques. For example, a UE may transmit, to an AN, a request to establish a RRC connection with a PN, and the AN may further transmit, to the PN, the request received from the UE to establish the RRC connection with the PN. After receiving the request, the PN may transmit, to the AN, one or more RRC connection parameters for the RRC connection with the UE, and the AN may further transmit, to the UE, the one or more connection parameters received from the PN for establishing the RRC connection with the PN. Based on the one or more parameters received from the AN, the UE may establish the RRC connection with the PN.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive one or more sidelink communications on a sidelink between the UE and another UE. The UE may transmit one or more hybrid automatic repeat request (HARQ) feedback communications, associated with the one or more sidelink communications, on the sidelink and in a HARQ feedback resource included in a multi-slot feedback reporting period. The HARQ feedback resource may include a set of negative acknowledgement (NACK) resources or the set of NACK resources and a set of acknowledgement (ACK) resources. Numerous other aspects are provided.

Abstract: Wireless communication systems and methods related to sidelink communications are provided. A first user equipment (UE) determines a discontinuous operation configuration that indicates an on-duration period for a sidelink communication and a cycle of discontinuous operation. The first UE communicates with at least one other UE during the on-duration period indicated by the discontinuous operation configuration. The first UE uses a base configuration and an on-duration parameter, an offset parameter, and a cycle parameter to determine a discontinuous operation configuration for the first UE.

Abstract: An ego vehicle determines an intended maneuver and identifies a first set of agents for coordinating the intended maneuver. The ego vehicle also determines a spatial distance for obtaining a level of communication reliability with the set of agents that is greater than a communication reliability threshold. The ego vehicle further applies the determined spatial distance to a sensor-sharing message. The ego vehicle also transmits the sensor-sharing message to a second set of agents within the determined range. The ego vehicle performs the intended maneuver.

Abstract: Methods, systems, and devices for wireless communication are described. A transmitting device may select an orthogonal metric based at least in part on at least one of each direction of a plurality of directions to transmit millimeter wave discovery signals or a location parameter associated with the transmitting device. The transmitting device may transmit, in the each direction of the plurality of directions, the millimeter wave discovery signals, where the each transmitted millimeter wave discovery signal has a different orthogonal metric applied that was selected based at least in part on the at least one of the each direction or the location parameter.