Abstract: Methods, systems, and devices for wireless communications are described. A communication device supports sidelink communications, including device-to-device (D2D) communications and vehicle-based communications. The communication device receives, from another device, a discontinuous transmission (DTX) configuration for a sidelink connection between the communications device and the other device. Based on the received DTX configuration, the communications device determines a discontinuous reception (DRX) configuration and transmit, to the other device, the determined DRX configuration. The devices experience power savings, among other results according to the DTX configuration or the DRX configuration.

Abstract: Disclosed are techniques for wireless communication. In an aspect, a transmitter user equipment (UE) determines a first demodulation reference signal (DMRS) pattern for a first slot allocated for transmission over a sidelink between the transmitter UE and a receiver UE, wherein the first DMRS pattern is determined based at least on the first slot having a first slot format of two or more slot formats, and transmits, to the receiver UE, DMRS in the first slot according to the first DMRS pattern. In an aspect, the receiver UE determines the first DMRS pattern for the first slot based at least on the first slot having the first slot format, and receives, from the transmitter UE, DMRS in the first slot according to the first DMRS pattern.

Abstract: Aspects relate to managing a device-to-device communication link via radio resource control (RRC) layer signaling. In an example operation, a first wireless communication device establishes a unicast link with a second wireless communication device over a device-to-device communication interface and determines that the unicast link is to be reconfigured with at least one updated parameter. The first wireless communication device then sends a link reconfiguration request to the second wireless communication device via a first RRC message over the communication interface. The first RRC message includes the at least one updated parameter. The first wireless communication device receives a link reconfiguration response from the second wireless communication device via a second RRC message over the communication interface based on the link reconfiguration request and determines whether to reconfigure the unicast link using the at least one updated parameter based on the received link reconfiguration response.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment may receive, from a base station, a slot configuration identifying one or more symbols to be used for sidelink communications. The user equipment may transmit an indication of the slot configuration to another user equipment to configure the other user equipment to use the identified one or more symbols for sidelink communications. Numerous other aspects are provided.

Abstract: Methods, systems, and devices for wireless communications are described. A communication device, which may be otherwise known as user equipment (UE), may identify a default modulation and coding scheme table and a preconfigured modulation and coding scheme table associated with a resource pool. The UE may receive, from a transmitting communication device, an indication of the preconfigured modulation and coding scheme table to use for upcoming sidelink communications. The UE may then communicate based on the preconfigured modulation and coding scheme table.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may perform at least one transmission of a communication, wherein the at least one transmission includes information indicating a feedback parameter for feedback regarding the at least one transmission, wherein the feedback parameter is a function of a control exclusion parameter of the UE. The UE may retransmit the communication when the feedback indicates that the at least one transmission was not received by a recipient device within the feedback parameter. Numerous other aspects are provided.

Abstract: Methods, systems, and devices for wireless communications are described, in which a user equipment (UE) may communicate with one or more other UEs using sidelink communications. Multiple UEs may form a sidelink communications group and provide for sidelink groupcast communications in which an identification of a UE is determined based at least in part on a member identification of the UE within the group. Each UE in the group may determine feedback resources for acknowledgment feedback within the group based on a UE identification and a size of the group.

Abstract: A user equipment (UE) may communicate with one or more other UEs using multiple transmissions in a device-to-device (D2D) communications deployment. A number of UEs may be configured with D2D resources, and a transmitting UE may identify available D2D resources from the configured resources. The transmitting UE may identify a resource for a first transmission of a D2D transmission from the available D2D resources, and may identify a second resource for a second transmission of the D2D transmission. The second transmission may be a blind HARQ transmission that may be transmitted to enhance the likelihood that one or more receiving UEs successfully receive the transmission. In some examples, the second resource may be identified based on other available resources within an predetermined time window around the first transmission.

Abstract: Various aspects of the disclosure relate to the selection and use of modulation and coding scheme (MCS) values. For example, a first MCS table may be used for a first condition and a second MCS table used for a second condition. The disclosure relates in some aspects to inter-device signaling that indicates which MCS table is to be used for communication between the devices.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may transmit a first message identifying a set of UEs comprising one or more other UEs with which the UE is engaging in sidelink communication. The UE may transmit a second message, based at least in part on a determination of a loss of a sidelink connection to a previously-connected UE of the set of UEs, identifying a subset of the set of UEs and indicating the loss of the sidelink connection. Numerous other aspects are provided.

Abstract: Aspects of the present disclosure provide synchronization techniques for user equipment (UEs) that may be otherwise unable to support sidelink communication a synchronized UE and may have also lost global navigation satellite system (GNSS) and/or Evolved Node Base Stations (eNBs) as a synchronization source. In such instance, the unsynchronized UE may utilize reference signals (RS) from the data packets received from other UEs to track the timing and perform autonomous timing adjustments based thereon for synchronized packet transmission or reception.

Abstract: Methods, systems, and devices for wireless communications are described in which two or more UEs of a wireless communications system may establish a sidelink connection. A first UE that is initiating sidelink communications may evaluate whether the sidelink connection can support a quality of service (QoS) for a data flow prior to admitting the data flow. The first UE may evaluate a link quality with one or more other UEs that are to use the data flow on the sidelink connection, evaluate system congestion of time/frequency resources that are available for the sidelink connection, or any combinations thereof, and admit the data flow based on the evaluation. A link quality of the sidelink connection may be determined based on a type of communication associated with the data flow, such as unicast communications with one other UE, multicast communications with multiple other UEs, or broadcast transmissions to multiple UEs.

Abstract: Methods, systems, and devices for wireless communications are described. A first wireless device may receive an indication of one or more parameters for communications over a sidelink channel during a first time period, where the one or more parameters may include a time threshold for a second resource pool. The wireless device may transmit data over a first resource pool of the sidelink channel during a first portion of the first time period based on the one or more parameters, the first resource pool including resources for communications between the first wireless device and a second wireless device. The wireless device may monitor the second resource pool during a second portion of the first time period for the time threshold, the second resource pool including resources for communications between the first wireless device and a third wireless device.

Abstract: Aspects described herein relate to receiving, over a sub-channel of multiple sub-channels, ultra-reliable quality-of-service (QoS) traffic from one or more UEs over a time duration wherein other sub-channels of the multiple sub-channels are used for initial ultra-reliable QoS transmissions from one or more other transmitting UEs over the time duration, and relaying, along with one or more other relaying UEs, the ultra-reliable QoS traffic over a subsequent time duration.

Abstract: Methods, systems, and devices for wireless communications are described. A device may determine a packet for transmission and determine whether to transmit a reservation signal prior to the transmission of the packet based in part on a condition. The condition may include, but is not limited to, a packet size, or a packet priority, or a combination thereof. According to the determination, the device may refrain from transmitting the reservation signal or allocate resources for the reservation signal from a same resource pool associated with the transmission of the packet or a dedicated resource pool according to a pre-reservation resource pattern.

Abstract: In one aspect, a method includes determining, by a user equipment (UE), a channel busy ratio (CBR) window for a CBR measurement for one or more resources; determining, by the UE, a CBR measurement value for the CBR window and for the one or more resources; determining, by the UE, a channel occupancy ratio (CR) window based on a first number of subframes used for a history of past transmissions and based on a second number of subframes used for future planned transmissions and corresponding retransmissions; and determining, by the UE, a CR value for the CR window based on subchannels used for the one or more resources for the first number of subframes and based on subchannels estimated for the one or more resources for the second number of subframes. In another aspect, a method includes determining a CR window based on a CBR measurement value.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may transmit concurrent messages over a sidelink channel to another UE and over an uplink channel to a base station. The UE may transmit, to a base station, a report indicating a capability of the UE to concurrently transmit over a sidelink channel and an uplink channel. The UE may receive, from the base station and based on the report, a transmission configuration scheduling a concurrent sidelink and uplink transmission within a resource shared by the sidelink channel and the uplink channel. The UE may then transmit the concurrent sidelink and uplink transmission within the resource shared by the sidelink channel and the uplink channel based on the transmission configuration. The other UE and the base station may receive the concurrent sidelink and uplink transmission and may decode different layers of the transmission.

Abstract: In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a UE. The apparatus may receive from a second device a first data packet in one or more receiving slots of a time division duplex frame that includes a plurality of slots. The apparatus may determine whether the first data packet is received incorrectly. The apparatus may wait until the end of the one or more receiving slots and may transmit to the second device a first NACK in a NACK feedback symbol in a configured slot after the end of the one or more receiving slots in response to determining that the first data packet was not received correctly.

Abstract: A deep-learning based method evaluates similarities of entities in decentralized identity graphs. One or more processors represent a first identity profile as a first identity graph and a second identity profile as a second identity graph. The processor(s) compare the first identity graph to the second identity graph, which are decentralized identity graphs from different identity networks, in order to determine a similarity score between the first identity profile and the second identity profile. The processor(s) then implement a security action based on the similarity score.

Abstract: Methods, systems, and devices for wireless communications are described. A communication device, which may be otherwise known as user equipment (UE), may identify a default modulation and coding scheme table and a preconfigured modulation and coding scheme table associated with a resource pool. The UE may receive, from a transmitting communication device, an indication of the preconfigured modulation and coding scheme table to use for upcoming sidelink communications. The UE may then communicate based on the preconfigured modulation and coding scheme table.