Abstract: Methods, systems, and devices for wireless communication are described. A wireless device may identify a configuration for transmitting ranging signals in a vehicle-based communication system. The configuration may identify a plurality of channels to be used for the ranging signals and timing for the ranging signals. The wireless device may transmit the configuration to a receiver and transmit ranging signals based at least in part on the configuration. The receiver may use the ranging signals to determine a distance between the receiver and the wireless device. The receiver may use the determined distance to update positioning information or operate a motor vehicle.

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.

Abstract: Techniques are described that support techniques for directional discovery in a millimeter wave communications system. A vehicle-to-everything (V2X) communications system may support beam discovery procedures that use directional beams to discover other entities, establish directional communication links with other entities, or maintaining directional communication links with other entities. The beam discovery procedure may include a sweep pattern where a transmitting entity may probe with directional beams in a plurality of beam directions. During a beam discovery procedure a transmitting entity may transmit discovery signals in a plurality of different directions and a receiving entity may listen for the discovery signals in a plurality of different directions. The sweep patterns of the transmitting entity and the receiving entity may be coordinated to increase a likelihood that the receiving entity will discover the transmitting entity.

Abstract: During device-to-device communication between two devices, a communication transmitted from a first UE to a second UE may not be reliably received by the second UE if the first UE is traveling at high speed. Therefore, a travel speed of a transmitting UE may be considered in determining a transmission configuration. According to an aspect, the UE may determine a travel speed of the UE. The UE may determine, based on the travel speed of the UE, a transmission configuration of the UE for device-to-device communication. The UE may transmit the device-to-device communication based on the transmission configuration.

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.

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: Techniques provided herein are directed toward addressing these and other issues by providing robust means for initializing an accelerometer that can take place even while a vehicle is in motion. Specifically, linear acceleration and velocity data can be estimated from wheel speeds, and angular velocity can be estimated with a gyroscope. The vehicle's acceleration can then be computed from these estimates, and subtracted from a total acceleration measured by the accelerometer to determine gravitational acceleration, which can then be accounted for in subsequent measurements taken by the accelerometer. A vehicle velocity may also be determined based on the vehicle's estimated angular velocity and linear velocity. Embodiments may also employ techniques for translating measurements taken in one coordinate frame to another coordinate frame for estimate determination and/or outlier compensation.

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: Various aspects described herein relate to techniques for connection setup procedures in a wireless communication system (e.g., a vehicle-to-everything (V2X) communication system in millimeter wave). In an aspect, the method includes identifying information for V2X communications, and initiating a random access procedure based on the identified information. The method further includes identifying one or more random access channel (RACH) resources based on the information, identifying one or more RACH response resources based on the one or more RACH resources, and performing directional communications using at least the one or more RACH resources or the one or more RACH response resources.

Abstract: Techniques are described for wireless communication at a wireless device. One method includes transmitting, during a TTI, a first message using a first MCS; and transmitting, during the TTI, a second message using a second MCS. The first message includes indications of a location, a heading, and a speed of the wireless device, and the second MCS is higher than the first MCS. Another method includes decoding a first message received during a TTI; performing a Doppler effect compensation for a second message based at least in part on the first message; and decoding the second message based at least in part on the Doppler effect compensation. The second message is also received during the TTI. The first message is decoded in accordance with a first MCS, and the second message is decoded in accordance with a second MCS, with the second MCS being higher than the first MCS.

Abstract: In an embodiment, a user equipment (UE) receives, from a fixed reference node, at least one round-trip propagation time (RTT) ranging scheduling message indicating a set of downlink (DL) ranging resource assignments and a set of uplink (UL) ranging resource grants, receives one or more DL ranging signals from the fixed reference node on a first set of resources identified by the set of DL ranging resource assignments, and transmits one or more UL ranging signals to the fixed reference node on a second set of resources identified by the set of UL ranging resource grants.

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, 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 features described herein relate to DM-RS design for a control channel and a data channel that maybe used for vehicular communications. In an aspect, a UE may determine a base DM-RS sequence associated with a control channel for V2V communication. The UE may further determine a DM-RS sequence based on the base DM-RS sequence and an identity of the UE, and transmit a plurality of DM-RS symbols within the control channel in a subframe using the DM-RS sequence. In another aspect, a UE may generate a plurality of DM-RS sequences, each DM-RS sequence maybe generated for a corresponding DM-RS symbol of a plurality of DM-RS symbols associated with a data channel for V2V communication based on a DM-RS symbol number of the corresponding DM-RS symbol. The UE may transmit the plurality of DM-RS symbols within the data channel in a subframe using the plurality of DM-RS sequences.

Abstract: In an embodiment, a user equipment (UE) receives, from a fixed reference node, at least one round-trip propagation time (RTT) ranging scheduling message indicating a set of downlink (DL) ranging resource assignments and a set of uplink (UL) ranging resource grants, receives one or more DL ranging signals from the fixed reference node on a first set of resources identified by the set of DL ranging resource assignments, and transmits one or more UL ranging signals to the fixed reference node on a second set of resources identified by the set of UL ranging resource grants.

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: 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: 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 and apparatus for configuring a UE to assist in mitigating network congestion include determining whether a data packet has expired based on a first parameter, which indicates an expiration of the data, and adjusting a transmission of the data packet based on the determination of whether the data packet has expired. In some aspects, the UE may drop the data packet upon determination that the data packet has expired. The UE may be configured detect to a first congestion level, receive a second congestion level from a second UE, and process a frame for transmission based on the first or second congestion level. The UE may be configured determine a priority, generate a data packet that includes a destination parameter or a source parameter, adjust radio resource parameters based on the destination parameter or source parameter, and transmit data packets according to adjusted radio resources.

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.