Abstract: Aspects of the present disclosure describe indicating per-packet quality of service (QoS) in communications by a wireless communications device. A packet from an application generated for a first radio access technology (RAT) can be obtained, where the packet includes a first QoS value associated with the first RAT, and/or the first QoS value can be mapped to a second QoS value associated with the second RAT. In another example, the QoS value can be indicated in the packet along with a reflective indicator indicating to use the QoS value in transmitting a response to the packet.

Abstract: Methods, systems, and devices for sidelink wireless communications are described in which a user equipment (UE) engaged in sidelink communications may provide for radio link maintenance of the sidelink connection by initiating a maintenance procedure, such as a measurement procedure, when one or more conditions are detected. The one or more conditions may include a threshold time being exceeded since a data transmission via the sidelink connection, or a threshold time being exceeded since a successful reception of a sidelink transmission from another UE. An access stratum layer at the initiating UE may format a data packet in the absence of higher layer data to be transmitted via the sidelink connection to initiate the maintenance procedure.

Abstract: Aspects relate to mechanisms for a wireless communication device to generate a superposition transmission of a sidelink signal to be transmitted to at least one receiving wireless communication device and an uplink signal to be transmitted to a base station. The wireless communication device may transmit the superposition transmission on resources allocated by the base station on a common carrier utilized for both sidelink and uplink transmissions. The superposition transmission includes a base layer corresponding to the uplink signal and an enhanced layer corresponding to the sidelink signal. The wireless communication device may further generate and transmit interference assistance information to the receiving wireless communication device for use by the receiving wireless communication device in canceling the base layer from the superposition transmission.

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 (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. 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 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, 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: Certain aspects of the present disclosure are generally directed to techniques for selecting a configuration for communication using vehicle to everything (V2X) type communication protocol. Certain aspects provide a method for wireless communication by a user-equipment (UE). The method generally includes determining one or more parameters corresponding to quality of service (QoS) information for communication of data using a V2X communication protocol, reporting the one or more parameters by transmitting a first message, receiving a second message indicating configuration information corresponding to the communication of the data using the V2X communication protocol, and communication the data based on the configuration information.

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: 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: 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: 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: 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 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: 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.