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. The method, system, and apparatus may include managing the operation mode of a user equipment in vehicle-to-everything communication. In some aspects, a user equipment may transmit an inactive request message (or a request message) to a base station to indicate the user equipment is switching from a base station scheduling mode (or a radio access network node scheduling mode) to a peer user equipment scheduling mode (or a roadside unit scheduling mode). The user equipment may receive an acknowledgment message from the base station indicating a state change to allow the peer user equipment scheduling mode. In some cases, the user equipment may receive an area identifier from the base station, and the area identifier may indicate an area where the peer user equipment scheduling mode is allowed.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a first wireless communication device may iterate a value of a channel access counter (CAC) to a trigger value based at least in part on configuring the value of the CAC. In some aspects, the first wireless communication device may utilize a channel access mechanism to select a set of time-frequency resources for a transmission of a packet based at least in part on iterating the value of the CAC to the trigger value. In some aspects, the first wireless communication device may transmit the packet to a second wireless communication device via the set of time-frequency resources based at least in part on utilizing the channel access mechanism to select the set of time-frequency resources for the transmission. Numerous other aspects are provided.

Abstract: Certain aspects of the present disclosure provide techniques for high reliability vehicle-to-everything (V2X) communications. Aspects of the present disclosure provide methods that may be performed by a first sidelink device. The first sidelink device may be a roadside unit (RSU) or a user equipment (UE). The first sidelink device may detect traffic from at least a second sidelink device and send the traffic to one or more other sidelink devices. A first sidelink device may receive reservation information from a first plurality of sidelink devices and schedule a second plurality of sidelink devices based on the reservation information.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment may determine hybrid automatic repeat request (HARQ) feedback for one or more sidelink communications received from one or more other UEs. The UE may identify one or more sets of subcarriers of a HARQ feedback occasion for the HARQ feedback for the one or more sidelink communications. The UE may transmit, to the one or more other UEs and on a sidelink, the HARQ feedback for the one or more sidelink communications using the one or more sets of subcarriers of the HARQ feedback occasion. 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 receive a packet at a transmitter of the UE for transmission in a sidelink network. The UE may select one or more resources for transmission of the packet based at least in part on a reservation status of the one or more resources, wherein at least one of the one or more resources is a reserved resource that is reserved by another UE. The UE may transmit the packet using the one or more resources based at least in part on selecting the one or more resources. Numerous other aspects are provided.

Abstract: Aspects described herein relate to managing coexistence of multiple radio access technology (RAT) components in a device. Information related to an upcoming time period can be sent to a first radio access technology (RAT) component from a second RAT component. The first RAT component can select a resource to transmit a first RAT packet to minimize collision with the upcoming time period of the second RAT.

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: Methods, systems, and devices for wireless communications are described that provide for dynamic resource avoidance and slot aggregation. The described techniques enable a user equipment (UE) in a vehicle-to-everything (V2X) system to select resources for varying transmission of a data packet (e.g., over multiple slots). The UE may determine a set of candidate transmission time intervals (TTIs) for transmission of the data packet based on a resource map, which may involve selecting resources that are unoccupied by other UEs as indicated by the resource map or preempting other UEs based on traffic priority or latency. The UE may transmit a reservation indication indicating resources to be reserved for subsequent transmissions (e.g., retransmission) and a UE receiving the reservation indication may update its resource map.

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: 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: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may determine a set of resource candidates in a sidelink communication system based at least in part on a set of resource assignments for a group of other UEs in the sidelink communication system. The UE may transmit a first part of a physical sidelink control channel (PSCCH) transmission. The UE may transmit a second part of the PSCCH transmission related to the first part of the PSCCH transmission to indicate a resource candidate, of the set of resource candidates, for a transmission associated with medium access control (MAC) protocol data units (PDUs) of a particular packet. Numerous other aspects are provided.

Abstract: Using a modulation and coding scheme for a control channel that is more conservative than needed to fulfill the control function may waste resources. To address this issue, a variable size control channel is provided. An apparatus in such a system may be configured to determine an aggregation level of a plurality of aggregation levels associated with a control channel. Each aggregation level of the plurality of aggregation levels is associated with a number of time-frequency resources dedicated for the control channel and a particular modulation and coding scheme used for modulating and coding control information in the control channel. The apparatus is configured to receive control information in the time-frequency resources associated with the aggregation level and decode the control information received in the time-frequency resources associated with the determined aggregation level. The decoding is based on the particular modulation and coding scheme associated with the determined aggregation level.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a first wireless communication device may iterate a value of a channel access counter (CAC) to a trigger value based at least in part on configuring the value of the CAC. In some aspects, the first wireless communication device may utilize a channel access mechanism to select a set of time-frequency resources for a transmission of a packet based at least in part on iterating the value of the CAC to the trigger value. In some aspects, the first wireless communication device may transmit the packet to a second wireless communication device via the set of time-frequency resources based at least in part on utilizing the channel access mechanism to select the set of time-frequency resources for the transmission. Numerous other aspects are provided.

Abstract: Methods, systems, and devices for wireless communications are described that may enable a user equipment (UE) to transmit sidelink data within an interference avoidance resource scheduling scheme. For example, a UE may determine to segment a data packet for transmission in a vehicle-to-everything (V2x) system (e.g., to ensure that each segment fits within one transmission time interval (TTI)). In some cases, a UE may identify a data packet for transmission, may determine that the size of the data packet exceeds a threshold size, may segment the data packet to ensure each segment fits within one TTI, and may transmit the data packet segments (e.g., to additional UEs), where said transmissions may be discontinuous. In some examples, a UE may determine to segment the data packet and then encode the data packet. Additionally or alternatively, the UE may determine to encode the data packet and then segment the data packet.

Abstract: User equipment (UEs) within a sidelink communications system may employ control forwarding techniques. For example, a UE may piggyback resource reservation information received from other UEs when broadcasting its own resource reservation. A UE that may be in line of sight (LOS) with two other UEs that themselves are in a non-line of sight (NLOS) situation and may include resource reservation information associated with other UEs when broadcasting the control information. For example, when forwarding control information, a UE may identify additional resources available in a transmission interval, and may convey neighbor control information (e.g., known resource reservations of other UEs in the sidelink communications system) using the additional resources. In some cases, the piggybacked resource reservation information associated with the other UEs may be selected based on the amount of additional resources in the transmission interval, a priority of known resource reservation information, etc.

Abstract: Methods, systems, and devices for wireless communications are described. Examples may include a receiving wireless device located in a first geographic zone receiving multiple signals from one or more transmitting wireless devices. The receiving wireless device may determine based on the received signals that the one or more transmitting devices are located in a second geographic zone. The receiving wireless device may determine configured transmit power information for each of the signals received from the transmitting wireless devices located in the second geographic zone. The receiving wireless device may estimate a path loss of wireless communications between the first geographic zone and the second geographic zone based on the configured transmit powers received in the signals. The receiving wireless device may communicate within the second geographic location based on the estimated path loss between the first geographic region and the second geographic region.

Abstract: An improved manner of transmitting and receiving messages in sidelink communication is presented in which a wireless device receives sidelink control information (SCI) that indicates a zone ID associated with a sidelink message. The wireless device determines a location of the wireless device and determines whether to send feedback for the sidelink message based, at least in part, on the zone ID associated with the sidelink message and the location of the wireless device. The feedback may include hybrid automatic repeat request (HARQ) feedback, and the sidelink message may include a groupcast message. The wireless device may further receive an indication of an intended range in the SCI and may determine whether to send the feedback based on a combination of the zone ID and the intended range for the sidelink message.

Abstract: Aspects of the present disclosure provide a method for wireless communications by a peer device. The method generates control information to schedule peer-to-peer communication. The control information includes a first portion with a first set of data and a second portion with a second set of data. The method then transmits the first portion of the control information in a first stage using first time and frequency resources. The first portion indicates a control information format of the second portion. The method further transmits the second portion of the control information in a second stage using second time and frequency resources and the indicated control information format.

Abstract: A method, a computer-readable medium, and an apparatus may involve wireless communication in a bundled TTI comprising a first TTI and a second TTI. A first UE may be configured to receive a first data transmission and a first reference signal from a second UE in the first TTI, to transmit a feedback to the second UE, and to receive a second data transmission having one or more transmission parameters adapted based on the feedback in the second TTI. In certain aspects, the first UE may be configured to transmit a first data transmission and a first reference signal to a second UE in the first TTI, to receive a feedback from the second UE, to adapt one or more transmission parameters for a second data transmission in the second TTI based on the feedback, and to transmit the second data transmission to the second UE in the second TTI.