Abstract: In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus is configured to transmit a first SA information in a first subframe. The apparatus is further configured to transmit a first data in the first subframe. The apparatus is configured to transmit a second SA information in a second subframe. The apparatus is also configured to transmit a second data in the second subframe. The first SA information includes information on the first data and the second data. The second SA information includes information on the second data.

Abstract: Methods, apparatuses, and computer-readable mediums for wireless communication are disclosed by the present disclosure. In an example, the present disclosure includes receiving, at a second device, a Random Access Channel (RACH) preamble from a first device, the RACH preamble initiates an access procedure between the first device and the second device; selecting, by the second device, a transmission resource associated with a second RACH message based on the RACH preamble; and transmitting, by the second device, the second RACH message on the selected transmission resource to the first device.

Abstract: Methods, apparatuses, and computer-readable mediums for wireless communication are disclosed by the present disclosure. In an example, a host device may determine a pool of preconfigured resources for discovery. The preconfigured resources are designated for one or more of: a discovery preamble, a query signal, a discovery message, and a random access preamble. The host device may transmit the discovery preamble on one or more resources designated for the discovery preamble. A client device may receive the discovery preamble and determine that the client device is interested in receiving information regarding the host device. The client device may transmit a query signal if interested. The host device may determine whether the query signal is received on a resource designated for the query signal in response to the discovery preamble. The host device may transmit a discovery message in response to receiving the query signal.

Abstract: Various aspects described herein relate to techniques for resource configuration for random access in a wireless communication system (e.g., a cellular vehicle-to-everything (CV2X) communication system). In an aspect, the method includes identifying a set of one or more random access channel (RACH) resources and configuration, sending a first RACH message including the set, and receiving a second RACH message including a resource selected from the set.

Abstract: Disclosed are techniques for using ranging signals to determine a position of a pedestrian user equipment (P-UE). In an aspect, a UE receives a plurality of ranging signals transmitted by one or more UEs, measures one or more properties of each of the plurality of ranging signals, and calculates an estimate of the position of the P-UE based on the one or more properties of each of the plurality of ranging signals. In an aspect, the P-UE transmits a plurality of ranging signals, receives a first message and a second message from first and second vehicle UEs (V-UEs), the first and second messages including first and second estimated positions of the P-UE and associated first and second confidences, and calculates an estimate of the position of the P-UE based on the first estimated position, the first confidence, the second estimated position, the second confidence, or a combination thereof.

Abstract: Methods, apparatuses, and computer-readable mediums for wireless communication are disclosed by the present disclosure. In an example, the present disclosure includes selecting, at a first device, a Random Access Channel (RACH) preamble identifier (ID) from a set of RACH preamble IDs based on a discovery procedure associated with a second device, wherein each RACH preamble ID from the set of RACH preamble IDs corresponds to at least one RACH preamble and is associated with the second device; and transmitting, from the first device, a RACH preamble associated with the selected RACH preamble ID to the second device.

Abstract: Methods, systems, and devices for wireless communications are described. In some wireless communications systems, a wireless device may broadcast a discovery preamble to identify a receiving device or to identify a suitable beam for communicating with a receiving device prior to broadcasting a discovery message to the receiving device. In such systems, the wireless device may use the techniques described herein to generate the discovery preamble and to reduce interference between discovery preamble transmissions and avoid data loss. In one example, a wireless device may append a cyclic prefix (CP) to a discovery preamble with a suitable length to protect the discovery preamble from interference from another transmission. In another example, the wireless device may generate a cyclically periodic signal including multiple copies of the discovery preamble so a receiving device may be able to receive a portion of the signal and identify the discovery preamble.

Abstract: Methods, systems, and devices for wireless communications are described. Some wireless communications systems support beamforming to improve the reliability of transmissions from a transmitting device to a receiving device. In some cases, a wireless device broadcasts information using beamforming. In such cases, in order to limit the overhead and power consumption associated with the broadcast, the wireless device utilizes the techniques described herein for broadcasting information using beamforming. In particular, rather than broadcasting large amounts of data in a beam-sweep, a wireless device broadcasts a relatively lightweight signal in a beam-sweep to first identify a receiving device and/or a suitable beam for communicating with a receiving device. Once the transmitting device identifies the receiving device and/or the suitable beam, the transmitting device broadcasts the data to be received by the receiving device.

Abstract: Techniques are described for performing beam sweep procedures as part of a device discovery procedure. A transmitting device (e.g., user equipment (UE) or base station) may generate a discovery preamble that is configured to indicate that a discovery message will be transmitted. The discovery preamble may be a smaller message (e.g., less bits) than the discovery message and thus may use fewer resources when it is being communicated. The transmitting device may transmit a plurality of signals that include a discovery preamble as part of beam sweep procedure. Once the transmitting device identifies a receiving device, the transmitting device may broadcast the discovery message. The discovery preamble may include a variety of different types of information including information relating to an identifier for the transmitting device, a discovery mode of the transmitting device, beam configurations, communication resources, beam sweep indexes, or a combination thereof.

Abstract: Improvement in co-existence of the LTE device-to-device communication with another device-to-device communication method is desired. The apparatus selects a countdown number within a size of a contention window including a plurality of slots before a target subframe. The apparatus determines whether each slot of the plurality of slots is idle or utilized while waiting for the target subframe. The apparatus counts down the countdown number during each of the determined idle slots. The apparatus determines whether the countdown number has reached a threshold number before the target subframe. The apparatus performs, when the countdown number is determined to have reached the threshold number, one of: deferring from transmitting until the target subframe, or transmitting a CUBS until a next subframe or the target subframe.

Abstract: Described are methods for interference detection and management in a millimeter wave communications system. A V2X communications system may support interference management procedures that comprise scheduling a system wide training interval in a transmission timeslot, suspending traffic transmissions on a link in the communications system during the training interval to perform training on the link, and resuming traffic transmissions on the link if interference is not detected during the training interval. Interference management procedures may also include receiving at a node, unique parameters transmitted from another node in a communication system during a discovery stage, determining whether interference will occur at the node based on the received unique parameters, and suspending transmissions to and from the node if it is determined interference will occur at the node.

Abstract: Methods, systems, and devices for ranging are described. A multi-phase distributed ranging technique includes transmitting and receiving vehicle information messages during a first time interval, where the vehicle information messages include at least a vehicle identifier and resource information. The multi-phase technique further includes transmitting and receiving ranging signals during a second time interval, and determining times of arrival of received ranging signals. A centralized ranging technique includes receiving resource assignments from an access point, transmitting ranging signals according to the resource assignments, and determining times of arrival of received ranging signals.

Abstract: In an example, a method for wireless communications by a first wireless device, is disclosed comprising obtaining information regarding an environment for wireless communications between the first wireless device and at least one second wireless device and adjusting one or more operating parameters for the wireless communications, based on the information. As described herein, information from one service or application in a first RAT is used by the first wireless device to enhance performance in another service or application in a second RAT by the first wireless device.

Abstract: A method for developing and reporting enhanced user equipment (UE) location information includes obtaining a global positioning system (GPS) location for a user equipment (UE), determining a location of at least one radio frequency (RF) antenna relative to the GPS location, developing a reference frame based at least in part on the location of the at least one RF antenna, determining a location of a structural element of the UE, and transmitting the GPS location, the location of the at least one RF antenna, and the location of the structural element of the UE.

Abstract: Aspects of the present disclosure are directed to device-to-device (D2D) and, more particularly, vehicle-to-vehicle (V2V) communication in which an efficient ranging protocol allows efficient ranging-assisted vehicle positioning. A vehicle transmits a first slot ID in a first control period, to indicate a first time slot for transmitting a first ranging signal in a ranging cycle including a plurality of time slots. The vehicle transmits the first ranging signal in the first time slot in the ranging cycle. From a second vehicle, the first vehicle receives a second ranging signal in a second time slot that is different from the first time slot in the ranging cycle. The first vehicle determines a first time-of-arrival (ToA) of the second ranging signal when received by the first vehicle, and transmits the first ToA in a second control period.

Abstract: Certain aspects of the present disclosure provide techniques for hierarchical communication for device-to-device (D2D) communications. In certain aspects, a method generally includes determining user equipment (UE) data comprising at least one of one or more parameters about the UE, one or more parameters about objects near the UE, or raw sensor data. The method further includes determining a first level for transmitting a first portion of the UE data based on content of the first portion of the UE data. The method further includes determining a first modulation coding scheme associated with the first level based on a mapping of a plurality of levels to a plurality of modulation coding schemes. The method further includes encoding the first portion of the UE data using the first modulation coding scheme and transmitting the first portion of the UE data from the UE to at least one second UE directly.

Abstract: Aspects of the disclosure relate to a vehicle, or a device or system connected to the vehicle, that enables the vehicle to act as a base station in a wireless communication network. The vehicle includes an access interface transceiver configured to communicate with devices within its passenger cabin, and a backhaul interface transceiver configured to communicate with the wireless communication network. By acting as a base station, the vehicle can establish and provide connectivity between the devices in its passenger cabin and the wireless communication network via the access transceiver and backhaul transceiver.

Abstract: An apparatus for wireless communication is provided. The apparatus determines, through sensors of a first vehicle, second-vehicle information associated with a second vehicle. In addition, the apparatus generates at least one safety message to include the determined second-vehicle information of the second vehicle. Further, the apparatus transmits the at least one safety message. The apparatus improves the performance/benefit of V2V communications technology by transmitting BSMs for other vehicles, including non-V2V vehicles without such V2V communications technology. Accordingly V2V vehicles will be able to better assess the traffic situation.

Abstract: Features of the present disclosure implementing techniques that allow the user equipment (UE) to autonomously (e.g., without the network control) manage timing synchronization of a plurality of carriers using sidelink synchronization signal (SLSS) from one or more other UEs in order to identify a synchronization source. A synchronization source associated with a frequency carrier from a set of frequency carriers may be selected according to one or more SLSS sync source selection techniques or rules. For instance, the described solution may be utilized to enable UEs to autonomously perform V2X carrier aggregation (CA). In some examples, the synchronization carrier(s) to be searched may be determined based on the SLSS capability of the UE (e.g., transmission and reception of SLSS capabilities of the UE).

Abstract: An apparatus for wireless communication of a UE determines to transmit data in a set of RBs to at least one other UE in at least one subframe. The at least one subframe includes a first subset of symbols configured for use for transmission collision avoidance signaling and a second subset of symbols configured for transmitting the data. The apparatus determines a subset of symbols of the first set of symbols within the set of RBs of the at least one subframe for transmitting at least one concatenated sequence. The apparatus transmits the at least one concatenated sequence in each symbol of the determined subset of symbols within the set of RBs of the at least one subframe to indicate that the data will be transmitted in the second set of symbols within the set of RBs of the at least one subframe.