Abstract: Certain aspects of the present disclosure provide techniques for sidelink communications in an unlicensed spectrum. A method that may be performed by a first device includes sensing that an unlicensed frequency band is idle, the unlicensed frequency band consisting of a plurality of subchannels. The method also includes, in response to sensing that the unlicensed frequency band is idle, transmitting, by the first device, at least one of a data signal or a reservation signal during an entire duration of a time period over one or more subchannels of the plurality of subchannels, the at least one of the data signal or the reservation signal reserving the unlicensed frequency band during the time period.

Abstract: Certain aspects of the present disclosure provide techniques for subchannel-based listen before talk (LBT). An example method that may be performed by a user equipment (UE) includes receiving one or more transmissions indicating one or more allocated subchannels of a frequency band that are allocated during a first time period, the frequency band comprising the one or more allocated subchannels and one or more unallocated subchannels during the first time period; sensing the one or more unallocated subchannels for at least a portion of the first time period prior to a second time period; and transmitting a signal within the frequency band during the second time period based on energy sensed for the one or more unallocated subchannels being less than a threshold.

Abstract: Methods, systems, and devices for wireless communications are described to reduce interference caused by power leakage. A first user equipment (UE) or a base station may select communication resources for a sidelink communication based on a distance between UEs reserving frequency resources in a same time window. The first UE or the base station may determine a distance parameter between the first UE and one or more other UEs (e.g., including a second UE) reserving frequency resources within the time window. The distance parameter may represent a physical distance between the first and second UEs or a reference signal received power of the second UE as received by the first UE. The first UE or the base station may select communication resources based on whether the distance parameter is below a threshold, and the first UE may communicate the sidelink communication using the selected resources.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment may receive information identifying a shared channel occupancy for a packet transmission resource; determine a range metric for die shared channel occupancy based at least in part on location information; determine whether to share the shared channel occupancy for packet transmission using the packet transmission resource based at least in part on the range metric; and selectively transmit one or more packets in the shared channel occupancy based at least in part on a result of determining whether to share the shared channel occupancy. Numerous other aspects are provided.

Abstract: Aspects relate to group-based reference signal broadcast in a wireless communication network. A first wireless communication device may transmit a first group formation broadcast message associated with a first positioning group comprising a first plurality of wireless communication devices including the first wireless communication device. The first wireless communication device may receive a second group formation broadcast message associated with a second positioning group comprising a second plurality of wireless communication devices including a second wireless communication device. The second positioning group may be associated with a channel occupancy time (CoT) in a sidelink channel. The CoT may comprise transmission opportunities configured to be used by the second plurality of wireless communication devices for communicating reference signals.

Abstract: Methods, systems, and devices for wireless communications are described. A first user equipment (UE) may transmit the sidelink message to a second UE via a sidelink communications channel of an unlicensed radio frequency spectrum band. The first UE or the second UE may transmit a reservation signal to retain the sidelink communication channel for corresponding feedback for the sidelink message (e.g., while the second UE generates a feedback transmission). The second UE may transmit the feedback transmission over the sidelink communication channel.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment may transmit, in a first slot within a channel occupancy time (COT), a first communication; determine whether one or more transmission criteria are satisfied for transmission of a second communication in a second slot within the COT; and selectively transmit the second communication in the second slot within the COT based at least in part on a result of determining whether the one or more transmission criteria are satisfied. Numerous other aspects are provided.

Abstract: Certain aspects of the present disclosure provide techniques for sidelink communications in an unlicensed spectrum. A method that may be performed by a device includes sensing a channel for interference in each of a plurality of time intervals in order of time until interference below a threshold is sensed for one of the plurality of time intervals or interference above the threshold is sensed for all of the plurality of time intervals, the plurality of time intervals being of a time window. The method may also include sensing interference to be above a threshold in a first portion of the one of the plurality of time intervals. The method may also include sensing interference to be below the threshold in a second portion of the one of the plurality of time intervals that occurs later in time than the first portion.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, an apparatus of a user equipment (UE) may transmit, over an unlicensed carrier, an initial transmission of a transport block (TB) satisfying a condition and an indication that a retransmission of the TB will be communicated over a licensed carrier. The apparatus may retransmit the TB over the licensed carrier based at least in part on a failure of the transmission of the TB over the unlicensed carrier. 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 generate a wake up signal to wake up a plurality of second UEs. The wake up signal may be based at least in part on location information associated with the UE, location information associated with one or more of the plurality of second UEs, or a combination thereof. The UE may further transmit, to the plurality of second UEs, the wake up signal. Accordingly, the plurality of second UEs may receive the wake up signal and monitor for messages from the second UE based at least in part on receiving the wake up signal. Numerous other aspects are provided.

Abstract: Methods, systems, and devices for wireless communications are described. A UE may support superimposed NR and LTE transmissions using an antenna port, in conjunction with an LTE-aware, NR slot structure (e.g., an NR V2X slot structure). In some aspects, the slot structure may protect portions of the LTE signal from interference, increasing LTE decoder robustness to interference which may provide opportunities for increasing the NR signal power. The UE may transmit a superimposed transmission of an LTE signal and an NR signal from a same antenna port in a same radio frequency resource. In some aspects, the slot structure may be modified so that the UE does not transmit when LTE reference signals are transmitted, so as to avoid interference with the LTE reference signals. A receiving UE may use the LTE reference signals to demodulate the LTE signal and the NR signal from the common time and frequency resources.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may generate a wake up signal to wake up a plurality of second UEs. The wake up signal may be based at least in part on location information associated with the UE, location information associated with one or more of the plurality of second UEs, or a combination thereof. The UE may further transmit, to the plurality of second UEs, the wake up signal. Accordingly, the plurality of second UEs may receive the wake up signal and monitor for messages from the second UE based at least in part on receiving the wake up signal. Numerous other aspects are provided.

Abstract: Methods, systems, and devices for wireless communications are described. A UE may support superimposed NR and LTE transmissions using an antenna port, in conjunction with an LTE-aware, NR slot structure (e.g., an NR V2X slot structure). In some aspects, the slot structure may protect portions of the LTE signal from interference, increasing LTE decoder robustness to interference which may provide opportunities for increasing the NR signal power. The UE may transmit a superimposed transmission of an LTE signal and an NR signal from a same antenna port in a same radio frequency resource. In some aspects, the slot structure may be modified so that the UE does not transmit when LTE reference signals are transmitted, so as to avoid interference with the LTE reference signals. A receiving UE may use the LTE reference signals to demodulate the LTE signal and the NR signal from the common time and frequency resources.

Abstract: Aspects described herein relate to methods for TDM based co-existence of V2X technologies. A method may comprise receiving a time division multiplexed configuration that is determined based on a distribution of a plurality of technologies in a communication system, the distribution corresponding to a traffic load of each technology and transmitting in accordance with channel access methods of one of the plurality of technologies during a resource allocated according to the received TDM configuration. In an aspect, each of the plurality of technologies operate in accordance with channel access methods defined for each technology.