Patent Description:
Wireless communication systems may include or support networks used for vehicle based communications, also referred to as vehicle-to-everything (V2X), eV2X, vehicle-to-vehicle (V2V) networks, cellular V2X (C-V2X) networks, or other similar networks. Vehicle based communication networks may provide always-on telematics where UEs, e.g., vehicle UEs (v-UEs), communicate directly to the network (V2N), to pedestrian UEs (V2P), to infrastructure devices (V2I), and to other v-UEs (e.g., via the network and/or directly). The vehicle based communication networks may support a safe, always-connected driving experience by providing intelligent connectivity where traffic signal/timing, real-time traffic and routing, safety alerts to pedestrians/bicyclist, collision avoidance information, etc., are exchanged.

Wireless communication systems may evolve such that different formats, protocols, RATs, and the like, change over time. Thus, wireless communication systems may be heterogeneous in that some devices may be configured for legacy operations and other devices may be configured for advanced operations. Coexistence of such devices within the same wireless communication system, e.g., a V2X based wireless communication system, may require migration and internetworking protocols. <NPL>, describes using key performance indicators (KPIs) to select which RAT technology to use for vehicle-to-everything (V2X) applications.

The following summarizes some aspects of the present disclosure to provide a basic understanding of the discussed technology. Its sole purpose is to present some concepts of one or more aspects of the disclosure in summary form as a prelude to the more detailed description that is presented later.

In the following, each of the described methods, apparatuses, systems, examples, and aspects which do not fully correspond to the invention as defined in the claims is thus not according to the invention and is, as well as the whole following description, present for illustration purposes only or to highlight specific aspects or features of the claims.

Other aspects, features, and embodiments of the technology will become apparent to those of ordinary skill in the art, upon reviewing the following description of specific, exemplary embodiments in conjunction with the accompanying figures. While features of the technology discussed below may be described relative to certain embodiments and figures below, all embodiments can include one or more of the advantageous features discussed. While one or more embodiments may be discussed as having certain advantageous features, one or more of such features may also be used in accordance with the various embodiments discussed. In similar fashion, while exemplary embodiments may be discussed below as device, system, or method embodiments it should be understood that such exemplary embodiments can be implemented in varying shapes, sizes, layouts, arrangements, circuits, devices, systems, and methods.

Aspects of the disclosure are initially described in the context of a wireless communications system. Heterogeneous wireless communications systems may evolve and include devices configured to use different formats, protocols, RATs, etc. In one example, a wireless communications system may support communications (e.g., V2X related communications) using a radio access network (RAN) Release <NUM> (r14) format, a RAN Release <NUM> (r15) format, a RAN Release <NUM> (r16) format, and the like. Moreover, certain evolutions may include the addition of advanced communication protocols, such as transitioning from an LTE configured protocol to an NR configured protocol, e.g., a r15 LTE V2X protocol and a r16 NR V2X protocol.

Moreover, certain formats/protocols may be associated with different features. For example, a r14 V2X configured device may support broadcast traffic messages, may support using safety messages, and the like. In some examples, a r14 V2X configured device may be configured to send safety messages (e.g., a basic safety message (BSM), a cooperative awareness message (CAM), and the like). A r15 V2X configured device may support co-existence with r14 devices, may or may not use the same scheduling assignment (SA) format, may use carrier aggregation (CA), may use different coding schemes (e.g., <NUM> quadrature amplitude modulation (QAM)), may use a shorter transmission time interval (TTI), and the like. In some examples, a r15 V2X configured device may send safety messages (e.g., either in r14 or r15 format), may decode r14 configured messages, etc. A r16 V2X configured device may be configured for LTE V2X operations and NR V2X operations. The r16 V2X device may include new functionality (e.g., higher MCS), different resource pools, support millimeter wave (mmW) communications, and may or may not be used for safety messages. For example, a r16 LTE V2X configured device may send safety messages in r14, r15, and/or r16 format configurations. A r16 NR V2X configured device may or may not send safety messages, may use different channels, different services, etc..

Aspects of the present disclosure provide for safety message compatibility, determine when to implement r15 features/enhancements, when to turn on r15/r16 format features/enhancements and coordination of NR operations, and/or detection of NR capabilities and services. For example, a UE (e.g., a V2X UE) may be configured such that an upper layer may control generation of a message by a lower layer based on a service identifier. For example, the upper layer may select the service identifier (e.g., provider service identifier (PSID)) based on the supported format. The upper layer may convey or otherwise provide the service identifier to the lower layer and, based on the service identifier, the lower layer may generate message(s) in the appropriate format (e.g., r14, r15, etc.).

In some aspects, a UE (e.g., a V2X UE) may be configured such that an upper layer may control the use of a channel by a lower layer based on parameters indicative of a RAT. For example, the upper layer of the UE may select which RAT to use for communications with neighboring UEs and select parameters associated with the RAT. The upper layer may convey or otherwise provide an indication of the parameters to the lower layer and the lower layer may transmit on that channel based on the indication.

In some aspects, a UE (e.g., a V2X UE) may select the format to use for communicating with neighboring UEs. For example, the UE may determine that it supports multiple formats (e.g., r14, r15, r16, LTE, NR) and then monitor messages received from neighboring UEs. The UE may use any indications in the messages to determine which formats the neighboring UEs support. Accordingly, the UE may select the format to use for communications with the neighboring UEs dependent upon the indicated formats received in the messages. In one non-limiting example, the UE may select a r15 or r16 format to use when all neighboring UEs support such formats. However, when a neighboring UE only supports r14, the UE may select a r14 format for communications with the neighboring UEs.

Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to eV2X RAT migration.

While aspects and embodiments are described in this application by illustration to some examples, those skilled in the art will understand that additional implementations and use cases may come about in many different arrangements and scenarios. Innovations described herein may be implemented across many differing platform types, devices, systems, shapes, sizes, packaging arrangements. For example, embodiments and/or uses may come about via integrated chip embodiments and other non-module-component based devices (e.g., end-user devices, vehicles, communication devices, computing devices, industrial equipment, retail/purchasing devices, medical devices, AI-enabled devices, etc.). While some examples may or may not be specifically directed to use cases or applications, a wide assortment of applicability of described innovations may occur. Implementations may range a spectrum from chip-level or modular components to non-modular, non-chip-level implementations and further to aggregate, distributed, or OEM devices or systems incorporating one or more aspects of the described innovations. In some practical settings, devices incorporating described aspects and features may also necessarily include additional components and features for implementation and practice of claimed and described embodiments. For example, transmission and reception of wireless signals necessarily includes a number of components for analog and digital purposes (e.g., hardware components including antenna, RF-chains, power amplifiers, modulators, buffer, processor(s), interleaver, adders/summers, etc.). It is intended that innovations described herein may be practiced in a wide variety of devices, chip-level components, systems, distributed arrangements, end-user devices, etc. of varying sizes, shapes, and constitution.

<FIG> illustrates an example of a wireless communications system <NUM>, in accordance with one or more aspects of the present disclosure. The wireless communications system <NUM> includes base stations <NUM> (e.g., gNBs <NUM>-a including access node controller(s) (ANC)(s) <NUM>-b, and/or radio heads (RHs) <NUM>-c), UEs <NUM>, and a core network <NUM>. In some examples, the wireless communications system <NUM> may be a LTE, LTE-Advanced (LTE-A) network, or a NR network. In some cases, wireless communications system <NUM> may support enhanced broadband communications, ultra-reliable (i.e., mission critical) communications, low latency communications, and communications with low-cost and low-complexity devices.

Each base station <NUM> may provide communication coverage for a respective geographic coverage area <NUM>. Control information and data may be multiplexed on an uplink channel or downlink according to various techniques. Control information and data may be multiplexed on a downlink channel, for example, using time division multiplexing (TDM) techniques, frequency division multiplexing (FDM) techniques, or hybrid TDM-FDM techniques. In some examples, the control information transmitted during a transmission time interval (TTI) of a downlink channel may be distributed between different control regions in a cascaded manner (e.g., between a common control region and one or more UE-specific control regions).

A UE <NUM> may also be referred to as a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology. A UE <NUM> may also be a cellular phone, a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a tablet computer, a laptop computer, a cordless phone, a personal electronic device, a handheld device, a personal computer, a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, a machine type communication (MTC) device, an appliance, an automobile, or the like.

In some cases, an MTC device may operate using half-duplex (one-way) communications at a reduced peak rate. MTC devices may also be configured to enter a power saving "deep sleep" mode when not engaging in active communications. In some cases, MTC or IoT devices may be designed to support mission critical functions and wireless communications system may be configured to provide ultra-reliable communications for these functions.

At least some of the network devices, such as base station <NUM> may include subcomponents such as an access network entity <NUM>-b, which may be an example of an access node controller (ANC). Each access network entity <NUM>-b may communicate with a number of UEs <NUM> through a number of other access network transmission entities <NUM>-c, each of which may be an example of a smart radio head, or a transmission/reception point (TRP).

Wireless communications system <NUM> may operate in an ultra-high frequency (UHF) frequency region using frequency bands from <NUM> to <NUM> (<NUM>), although some networks (e.g., a wireless local area network (WLAN)) may use frequencies as high as <NUM>. This region may also be known as the decimeter band, since the wavelengths range from approximately one decimeter to one meter in length. UHF waves may propagate mainly by line of sight, and may be blocked by buildings and environmental features. However, the waves may penetrate walls sufficiently to provide service to UEs <NUM> located indoors. Transmission of UHF waves is characterized by smaller antennas and shorter range (e.g., less than <NUM>) compared to transmission using the smaller frequencies (and longer waves) of the high frequency (HF) or very high frequency (VHF) portion of the spectrum. In some cases, wireless communications system <NUM> may also utilize extremely high frequency (EHF) portions of the spectrum (e.g., from <NUM> to <NUM>). This region may also be known as the millimeter band, since the wavelengths range from approximately one millimeter to one centimeter in length. Thus, EHF antennas may be even smaller and more closely spaced than UHF antennas. In some cases, this may facilitate use of antenna arrays within a UE <NUM> (e.g., for directional beamforming). However, EHF transmissions may be subject to even greater atmospheric attenuation and shorter range than UHF transmissions.

Thus, wireless communications system <NUM> may support mmW communications between UEs <NUM> and base stations <NUM>. Devices operating in mmW or EHF bands may have multiple antennas to allow beamforming. That is, a base station <NUM> may use multiple antennas or antenna arrays to conduct beamforming operations for directional communications with a UE <NUM>. Beamforming (which may also be referred to as spatial filtering or directional transmission) is a signal processing technique that may be used at a transmitter (e.g., a base station <NUM>) to shape and/or steer an overall antenna beam in the direction of a target receiver (e.g., a UE <NUM>). This may be achieved by combining elements in an antenna array in such a way that transmitted signals at particular angles experience constructive interference while others experience destructive interference.

Multiple-input multiple-output (MIMO) wireless systems use a transmission scheme between a transmitter (e.g., a base station <NUM>) and a receiver (e.g., a UE <NUM>), where both transmitter and receiver are equipped with multiple antennas. Some portions of wireless communications system <NUM> may use beamforming. For example, base station <NUM> may have an antenna array with a number of rows and columns of antenna ports that the base station <NUM> may use for beamforming in its communication with UE <NUM>. Signals may be transmitted multiple times in different directions (e.g., each transmission may be beamformed differently). A mmW receiver (e.g., a UE <NUM>) may try multiple beams (e.g., antenna subarrays) while receiving the synchronization signals.

In some cases, the antennas of a base station <NUM> or UE <NUM> may be located within one or more antenna arrays, which may support beamforming or MIMO operation. One or more base station antennas or antenna arrays may be collocated at an antenna assembly, such as an antenna tower. A base station <NUM> may multiple use antennas or antenna arrays to conduct beamforming operations for directional communications with a UE <NUM>.

In some cases, wireless communications system <NUM> may be a packet-based network that operates according to a layered protocol stack. The MAC layer may also use Hybrid Automatic Repeat Request (HARQ) to provide retransmission at the MAC layer to improve link efficiency. In the control plane, the Radio Resource Control (RRC) protocol layer may provide establishment, configuration, and maintenance of an RRC connection between a UE <NUM> and a network device <NUM>-c, network device <NUM>-b, or core network <NUM> supporting radio bearers for user plane data.

Time intervals in LTE or NR may be expressed in multiples of a basic time unit (which may be a sampling period of Ts = <NUM>/<NUM>,<NUM>,<NUM> seconds). Time resources may be organized according to radio frames of length of <NUM> (Tf = 307200Ts), which may be identified by a system frame number (SFN) ranging from <NUM> to <NUM>. Each frame may include ten <NUM> subframes numbered from <NUM> to <NUM>. A subframe may be further divided into two. <NUM> slots, each of which contains <NUM> or <NUM> modulation symbol periods (depending on the length of the cyclic prefix prepended to each symbol). Excluding the cyclic prefix, each symbol contains <NUM> sample periods. In some cases the subframe may be the smallest scheduling unit, also known as a TTI. In other cases, a TTI may be shorter than a subframe or may be dynamically selected (e.g., in short TTI bursts or in selected component carriers using short TTIs).

A resource element may consist of one symbol period and one subcarrier (e.g., a <NUM> frequency range). A resource block may contain <NUM> consecutive subcarriers in the frequency domain and, for a normal cyclic prefix in each orthogonal frequency division multiplexing (OFDM) symbol, <NUM> consecutive OFDM symbols in the time domain (<NUM> slot), or <NUM> resource elements. The number of bits carried by each resource element may depend on the modulation scheme (the configuration of symbols that may be selected during each symbol period). Thus, the more resource blocks that a UE receives and the higher the modulation scheme, the higher the data rate may be.

Wireless communications system <NUM> may support operation on multiple cells or carriers, a feature which may be referred to as carrier aggregation (CA) or multi-carrier operation. A carrier may also be referred to as a component carrier (CC), a layer, a channel, etc. The terms "carrier," "component carrier," "cell," and "channel" may be used interchangeably herein. A UE <NUM> may be configured with multiple downlink CCs and one or more uplink CCs for carrier aggregation.

An eCC may be characterized by one or more features including: wider bandwidth, shorter symbol duration, shorter TTIs, and modified control channel configuration. An eCC may also be configured for use in unlicensed spectrum or shared spectrum (where more than one operator is allowed to use the spectrum). An eCC characterized by wide bandwidth may include one or more segments that may be utilized by UEs <NUM> that are not capable of monitoring the whole bandwidth or prefer to use a limited bandwidth (e.g., to conserve power).

A shorter symbol duration is associated with increased subcarrier spacing. A device, such as a UE <NUM> or base station <NUM>, utilizing eCCs may transmit wideband signals (e.g., <NUM>, <NUM>, <NUM>, <NUM>, etc.) at reduced symbol durations (e.g., <NUM> microseconds). A TTI in eCC may consist of one or multiple symbols. In some cases, the TTI duration (that is, the number of symbols in a TTI) may be variable.

A shared radio frequency spectrum band may be utilized in an NR shared spectrum system. For example, an NR shared spectrum may utilize any combination of licensed, shared, and unlicensed spectrums, among others. The flexibility of eCC symbol duration and subcarrier spacing may allow for the use of eCC across multiple spectrums. In some examples, NR shared spectrum may increase spectrum utilization and spectral efficiency, specifically through dynamic vertical (e.g., across frequency) and horizontal (e.g., across time) sharing of resources.

In some cases, wireless communication system <NUM> may utilize both licensed and unlicensed radio frequency spectrum bands. For example, wireless communication system <NUM> may employ LTE License Assisted Access (LTE-LAA) or LTE Unlicensed (LTE U) radio access technology or NR technology in an unlicensed band such as the <NUM> Industrial, Scientific, and Medical (ISM) band. When operating in unlicensed radio frequency spectrum bands, wireless devices such as base stations <NUM> and UEs <NUM> may employ listen-before-talk (LBT) procedures to ensure the channel is clear before transmitting data. In some cases, operations in unlicensed bands may be based on a CA configuration in conjunction with CCs operating in a licensed band. Operations in unlicensed spectrum may include downlink transmissions, uplink transmissions, or both. Duplexing in unlicensed spectrum may be based on FDD, TDD or a combination of both.

In some aspects, a UE <NUM> may include a UE communications manager <NUM>. The UE communications manager <NUM> may be configured to transmit a message to a neighboring UE <NUM> via multiple formats, identify a service parameter indicative of a format to be used for the message. The UE communications manager <NUM> may convey information indicating the service parameter from a first layer of the UE <NUM> to a second layer of the UE <NUM>, wherein the first layer is an upper layer with respect to the second layer. The UE communications manager <NUM> may generate, by the second layer and based at least in part on the information, the message in the format for communicating with the neighboring UE.

Additionally, the UE communications manager <NUM> may be configured to transmit a message to a neighboring UE via multiple protocols and select one or more parameters indicative of a RAT to be used for the message. The UE communications manager <NUM> may convey information indicating the one or more parameters from a first layer of the UE <NUM> to a second layer of the UE <NUM>, wherein the first layer is an upper layer with respect to the second layer. The UE communications manager <NUM> may instantiate, by the second layer and based at least in part on the parameter, a channel for communications with the neighboring UE according to the RAT.

Further, the UE communications manager <NUM> may determine that the UE <NUM> supports communicating using a first format and a second format, the first format being a legacy format with respect to the second format. The UE communications manager <NUM> may receive one or more messages from one or more neighboring UEs. The UE communications manager <NUM> may determine, based at least in part on the one or more messages, that the one or more neighboring UEs support communications using the second format. The UE communications manager <NUM> may select the second format for communications with the one or more neighboring UEs.

<FIG> illustrates an example of a process <NUM> that supports eV2X RAT migration, in accordance with one or more aspects of the present disclosure. In some examples, process <NUM> may implement aspects of wireless communication system <NUM>. Process <NUM> may include a UE <NUM>, which may be an example of the corresponding devices described herein. In some aspects, the UE <NUM> may be a V2V or V2X configured device or UE. UE <NUM> may include a first layer <NUM> and a second layer <NUM>. The first layer <NUM> may be an upper layer with respect to the second layer <NUM>. Broadly, process <NUM> illustrates one example of the UE <NUM> configured to determine safety message compatibility and/or when to use r15 features/enhancements.

In some aspects, process <NUM> may provide for BSM/CAM/Decentralized Environmental Notification (DENM) compatibility. According to r14 protocols, such safety messages may be required to be decodable by all vehicles in a V2X implementation. However, a r14 configured UE may not be able to decode a r15 configured message, e.g., r15 messages may use a higher MCS, such as <NUM> QAM. Moreover, process <NUM> may provide for a determination of when to use r15 configured features/enhancements. This may be particularly relevant when the upper layer does not understand which formats are being used, for example.

In some aspects, a group of V2V or V2X configured UEs may include a mix of r14, r15, and r16 configured UEs. However, the safety messages exchanged between the UEs may need to be understood by all UEs within range. In some aspects, process <NUM> implements one example of where the upper layer (e.g., the first layer <NUM>) selects the format and/or protocol to use for communications with other UEs, e.g., other V2V or V2X configured UEs. Generally, the UE <NUM> may be configured to transmit message(s) to neighboring UEs using multiple formats, protocols, etc..

At <NUM>, the first layer <NUM> may identify or select a service parameter that is indicative of a format to be used for communicating messages to the neighboring UEs. In some aspects, the first layer <NUM> may identify or select parameter(s) indicative of or otherwise associated with a RAT that may be used for communicating the messages to the neighboring UEs.

In some aspects, while some services (e.g., safety messages) may have legacy support, certain features may be configured for r15 configurations and above and therefore may only use a r15 (or r16) configuration formats. For example, the service parameter may be a service identifier, e.g., a PSID, an intelligent transport system application object identifier (ITS-AID), and the like. In some aspects, the service parameter may be associated with the particular service, e.g., a vehicle platooning operation, a cooperative adaptive cruise control operation, a sensor sharing operation, and the like. In some aspects, a particular service may obtain a service identifier for the service and the UE <NUM> may be configured with a list of PSIDs that can use r15 configuration formats. In another example, the UE <NUM> may be configured such that any PSID not configured or associated with legacy support (e.g., r14 support) may be assumed to use r15 configuration formats. UE <NUM> may determine the message transmission format based on the r15 configurations.

In some aspects, the first layer <NUM> may identify the parameter by identifying a QoS metric, a PPPP, a service identifier (e.g., PSID), an identifier associated with the second layer <NUM> (e.g., a L2ID or L2 ID). Accordingly, the selected parameter may include one or more of the QoS metric, the PPPP, the PSID, the L2ID, and the like. The QoS metric may be associated with a VQI. In some aspects, the first layer <NUM> may access a preconfigured list or rule to identify the parameters and/or may receive the list or rule from a network entity.

Thus, in some aspects, UE <NUM> may classify the messages (e.g., the messages are sent down to the second layer <NUM> with the PSID) based on the PSID/ITS-AID. UE <NUM> may be configured with a mapping between the PSID and the service parameters, e.g., a mapping between the PSID and which RAN release will be used to communicate safety messages. In some aspects, the mapping may be between a combination of any of the PSID, QoS metric, the PPPP, and the L2ID to the RAT or transmission characteristics and parameters. In some aspects, the mapping may be between the combination of any of the PSID, QoS metric, the PPPP, and the L2 ID to a flag. The flag may indicate for example, if the message needs to be decoded by a legacy UE, e.g. using r14 format. The first layer <NUM> may specify or otherwise determine the second layer <NUM> behavior in the presence of the flag, e.g., may determine whether the second layer <NUM> uses r14, r15, or r16 protocols. In some examples, the flag may provide an indication of whether legacy support is required, e.g., a binary flag. The flag may be decided by the first layer <NUM> based on a combination of the PPPP, the PSID, etc. The flag may be passed to the second layer <NUM> together with the data packet. Based on the flag, the second layer <NUM> may determine which format to use, e.g., r14/r15, a reduced rate MCS, etc. In some aspects, the flag may be extended to indicate additional information and, in some instances, used for r16 regarding the support of a legacy RAT. That is, the first layer <NUM> may use the PSID based control when deciding the second layer <NUM> behavior.

At <NUM>, the first layer <NUM> may convey to the second layer <NUM> a message or information indicating the service parameter. In some aspects, the first layer <NUM> may convey to the second layer <NUM> a message or information indicating the parameter(s) indicative of the RAT to be used for inter-UE communications.

In some aspects, the first layer <NUM> may include in the message or information the flag to indicate the service parameter. For example, the first layer <NUM> may determine whether to include the flag in the message or information based on a listing of service identifiers (e.g., PSID) associated with the format. As also discussed, the first layer <NUM> may classify the message or information based on the service parameter.

In some aspects, the first layer <NUM> may convey the information on a per-packet basis. For example, the first layer <NUM> may generate each packet to indicate the QoS metric, the PPPP, the PSID, and/or the L2ID to the second layer <NUM>. In some aspects, this may include a per packet indication from the first layer <NUM> (e.g., an application layer). The application layer may associate with each packet the QoS metric: PPPP, etc. In some aspects, this may be associated with key performance indicators (KPI) associated with the communications with the neighboring UEs. In some aspects, a VQI table may be standardized to reflect KPIs for the application layer to use, e.g., VQI-to-packet delay budget (PDB), message frequency, message size range, reliability, rate range etc. The RAT may be chosen per packet based on the VQI.

At <NUM>, the second layer <NUM> may generate a message in the format for communicating with the neighboring UE based on the service parameters indicated in the information. In some aspects, the second layer <NUM> may use a channel for communicating with the neighboring UEs according to the RAT associated with the parameters. The UE <NUM> may transmit the generated message and/or use the channel to the neighboring UEs according to the format/RAT.

In some aspects, the second layer <NUM> may generate the message as one of a plurality of available versions of V2X messages, e.g., depending upon the V2X service, based on the format/RAT, etc. Thus, UE <NUM> may communicate with the neighboring UEs using the generated message that, in some instances, may be a safety message associated with vehicle-based operations, e.g., V2V, V2X, etc. In some aspect, the second layer <NUM> may generate the message with other access technology, e.g., using direct short range communications (DSRC)/wireless access in vehicular environments (WAVE) protocols beside LTE or NR V2X, if indicated in the information.

In some aspects, the second layer <NUM> may generate or configure a virtual bearer based on the parameter(s) indicated from the first layer <NUM>. For example, the virtual bearer may include a logical bearer and/or a radio bearer. In some examples, the virtual bearer may include an LTE V2X bearer and a set of NR bearers (the set of NR bearers may include zero or one or more NR bearers). In some aspects, the set of NR bearers may be generated dynamically, e.g., generated by the second layer <NUM> based on the parameters selected by the first layer <NUM>. In some aspects, the virtual bearer is generated based on receiving a message from neighboring UE(s), e.g., triggered by the messages. Receiving the message(s) may trigger activation of an application associated with the virtual bearer. In some aspects, the second layer <NUM> may use an LTE channel by default and then set up a NR channel dynamically based on receiving message(s) from the neighboring UEs. In some aspects, there may be multiple LTE V2X bearers established, representing r14 and r15 formats, respectively.

In some aspects, the virtual bearer set up may be based on a QoS request from the application layer (e.g., the first layer <NUM>). In some examples, this may be implemented for non-broadcast traffic (e.g., a groupcast and/or unicast transmission). The application layer may send a setup request for a specific combination of L2 ID, PPPP, VQI, and/or QoS metrics. This may trigger the another layer (e.g., a V2X layer) to request the lower layer (e.g., the second layer <NUM>) to setup a virtual bearer, which in turn determines the RAT. The following traffic (e.g., messages, communications, etc.) may be identified by the PSID and L2 ID by the V2X layer. In the instance where the requested RAT is not supported, the application layer may be informed via a reject message, and it may not send such traffic according to the protocols.

In some aspects, the virtual bearer may determine the logical bearer and/or the physical characteristics of the bearer (e.g., physical layer resources, coding schemes, etc.). The configuration may indicate the mapping of the packets to the virtual bearer (e.g., in an uplink traffic flow template (TFT) manner). The virtual bearer concept (LTE V2X being the default bearer and setup by default; and a NR with different NR bearers with different characteristics and set up on demand) may be associated with different triggers/control logic for setting up the virtual bearer. In one example, receiving a message at lower layer (e.g., second layer <NUM>) on a NR, receiving an indication from the LTE V2X layer, e.g. BSM/CAM/DENM messages, and/or an application layer trigger. In some aspects, any extra function may be specified at the LTE V2X layer, e.g. similar to an uplink TFT enforcement at the non-access stratum (NAS) layer for a LTE Uu interface. The mapping information, e.g., TFT, may be preconfigured on the UE, or provisioned/signaled from the network when needed. For example, upper layer provisioning protocol or access stratum protocol, e.g. RRC, may be used for disseminating such configuration. The bearer binding may include a "logical channel + radio bearer + RAT" towards the bearer, e.g., for the transmit side. On the receive side, receiving a packet on a RAT may trigger setting up of the bearer and/or wake up of the application layer, e.g., similar to an internet-of-things (IoT) triggering message. In some aspects, the BSM may be extended to turn on the other UE's application/bearer (e.g. BSM includes additional PSIDs or other application layer identifiers for an application the UE <NUM> is sending on other messages). For example, a BSM may have an associated PSID and UE <NUM> may be sending other types of messages, e.g., a local dynamic map (LDM) message, a signal phase and timing (SPAT) message, sensor sharing messages, and the like, and each additional message type may have an associated PSID (e.g., located in the header of the additional messages). In some aspects, additional information may be added to the LTE V2X layer header to indicate what service is running and trigger the receiver to setup the corresponding virtual bearer (or even wake up the application). The V2X layer header (above the PDCP layer) may be common for all the LTE and NR RATs and may include such extra information for triggering.

In some aspects, the spectrum may also play a role in the RAT selection. The UE <NUM> may be configured with PSID-to-spectrum mapping configuration and may use the available spectrum limitation to choose the RAT.

Thus, the second layer <NUM> may generate messages and/or instantiate a channel to use for communications with neighboring UE(s). Such communications may include vehicle-based operations, e.g., V2V, V2X, etc., operations. The communications according to the RAT may include a supported broadcast traffic function, a safety message function, a SA, a CA, a MCS, and/or a TTI.

<FIG> illustrates an example of a layer configuration <NUM> that supports eV2X RAT migration, in accordance with one or more aspects of the present disclosure. In some examples, layer configuration <NUM> may implement aspects of wireless communication system <NUM>. Layer configuration <NUM> may implement aspects of wireless communication system <NUM> and/or process <NUM>, as described herein. In some aspects, layer configuration <NUM> may be implemented on a UE, such as a V2X configured UE.

Layer configuration <NUM> may include an application layer <NUM>, a V2X layer <NUM> (e.g., that acts as a service layer), and/or a MAC/PHY layer <NUM> (e.g., that acts as a transport layer). The MAC/PHY layer <NUM> may be used to generate a LTE V2X RAT <NUM> and/or a NR V2X RAT <NUM>. The LTE V2X RAT <NUM> may be associated with r15 and/or r16 and the NR V2X RAT <NUM> may be associated with r16.

In some examples, the first layer described herein may refer to the application layer <NUM> and the second layer may refer to the MAC/PHY layer <NUM>. In some examples, the V2X layer <NUM> may be considered an intermediate layer, may be included in the first layer, and/or may be included in the second layer.

Thus, the application layer <NUM> may identify service parameter(s) indicative of a format to be used for messages and/or communications with neighboring UEs. The application layer <NUM> may convey information indicating the service parameter to the MAC/PHY layer <NUM> (e.g., via the LTE V2X layer <NUM>). The MAC/PHY layer <NUM> may generate the message and/or communications with the neighboring UE according to the format, e.g., as indicated in the information conveyed from the application layer <NUM>.

In some aspects, the application layer <NUM> may select parameter(s) indicative of a RAT to be used for the message and/or communications. The application layer <NUM> may convey information indicating the parameter(s) to the MAC/PHY layer <NUM>. The MAC/PHY layer <NUM> may use the parameter(s) to instantiate a channel for communications with the neighboring UEs according to the RAT.

<FIG> illustrates an example of a process <NUM> that supports eV2X RAT migration, in accordance with one or more aspects of the present disclosure. In some examples, process <NUM> may implement one or more aspects of wireless communication system <NUM>, process <NUM>, and/or layer configuration <NUM>, as described herein. Process <NUM> may include a UE <NUM> and a neighbor UE <NUM>, which may be examples of the corresponding devices described herein.

In some aspects, process <NUM> may support dynamic detection of the format(s) to use base on periodical safety messages (e.g., BSM/CAM, etc.). UE <NUM> may only use a legacy format (e.g., a r14 format) when other r14 configured UEs are present. Generally, UE <NUM> may detect the presence of r14 configured UEs (e.g., determine if neighboring UEs support r15 formats even when UE <NUM> is transmitting in a r14 format). UE <NUM> may decode messages received from neighboring UEs and decode the SA and/or header portions of the message to identify an indication of whether the neighboring UE supports r15 format, e.g., a capability indication. UE <NUM> may only use the r15 format when it does not receive any indication from neighboring UEs of r14 use for a configurable time period. In some aspects, process <NUM> may be implemented in addition to the features described with reference to process <NUM>. Process <NUM> may also support UE <NUM> determining when to use r15 features/enhancements.

At <NUM>, UE <NUM> may determine that it supports multiple formats. For example, UE <NUM> may determine that it supports communicating using a first format and a second format. The first format may be a legacy format with respect to the second format, e.g., the first format may be a r14 format and the second format may be a r15 and/or r16 format.

At <NUM>, neighbor UE <NUM> may transmit (and UE <NUM> may receive) message(s). In some aspects, the message(s) may carry or otherwise convey an indication that the neighbor UE <NUM> supports the second format, e.g., r15 and/or r16. For example, the SA associated with the message and/or a header in the message may carry or otherwise convey the indication that neighbor UE <NUM> supports the second format. In some aspects, the messages may be safety messages that are configured according to the first format, e.g., r14 configuration. In some aspects, the messages may include a service identifier (e.g., a PSID) that indicates the UE supports communicating using the second format.

At <NUM>, UE <NUM> may determine the supported formats of the neighboring UEs. For example, UE <NUM> may determine, based on the messages, whether the neighbor UE <NUM> supports communicating using the second format. UE <NUM> may determine the support by decoding a SA for the message. UE <NUM> may determine the support by decoding a header portion (or multiple header portions) in the messages, e.g., a MAC header, an RLC header, and/or a PDCP header, and the like.

At <NUM>, UE <NUM> may select the second format for communications with the neighbor UE <NUM>. For example, UE <NUM> may instantiate a LTE channel bearer by default and then set up a NR channel bearer(s) dynamically based on receiving a message from the neighboring UE that triggers setting up the NR channel bearer(s).

In some aspects of the described techniques, the UE <NUM> may be configured to detect neighbor UE <NUM> NR V2X capability. In the situation where NR V2X operations do not include safety applications, periodic safety messages may be absent (e.g., BSM/CAM). In other situations, r15/r16 LTE V2X may include safety messages, e.g., BSM/CAM may be transmitted periodically due to the safety mandate. In a first aspects, a LTE V2X assisted NR capability discovery may include, within a message sent using r14/r15 format, the indication of NR capability may be added to the message. This may include a field defined in r15 LTE V2X message format as reserved, and a r16 configured UE may set the field accordingly to indicate NR capability. In a second approach for standalone NR operations, a service/capability discovery messages may be transmitted over the NR directly. For example, UE <NUM> may send periodic capability discovery messages in broadcast mode over NR. In a third approach, an LTE based capability exchange may be used when NR transmission is needed. For example, UE <NUM> may request NR capability info from a specific target neighboring UE.

<FIG> shows a block diagram <NUM> of a wireless device <NUM> that supports eV2X RAT migration, in accordance with one or more aspects of the present disclosure. Wireless device <NUM> may be an example of aspects of a UE <NUM> as described herein. Wireless device <NUM> may include receiver <NUM>, communications manager <NUM>, and transmitter <NUM>. Wireless device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

Receiver <NUM> may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to eV2X RAT migration, etc.). Information may be passed on to other components of the device. The receiver <NUM> may be an example of aspects of the transceiver <NUM> described with reference to <FIG>. The receiver <NUM> may utilize a single antenna or a set of antennas.

Communications manager <NUM> may be an example of aspects of the communications manager <NUM> described with reference to <FIG>.

Communications manager <NUM> and/or at least some of its various sub-components may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions of the communications manager <NUM> and/or at least some of its various sub-components may be executed by a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in the present disclosure. The communications manager <NUM> and/or at least some of its various sub-components may be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations by one or more physical devices. In some examples, communications manager <NUM> and/or at least some of its various sub-components may be a separate and distinct component in accordance with various aspects of the present disclosure. In other examples, communications manager <NUM> and/or at least some of its various sub-components may be combined with one or more other hardware components, including but not limited to an I/O component, a transceiver, a network server, another computing device, one or more other components described in the present disclosure, or a combination thereof in accordance with various aspects of the present disclosure.

In some aspects, communications manager <NUM> may identify, at a UE that is configured to transmit a message to a neighboring UE via multiple formats, a service parameter indicative of a format to be used for the message. Communications manager <NUM> may convey information indicating the service parameter from a first layer of the UE to a second layer of the UE, where the first layer is an upper layer with respect to the second layer. Communications manager <NUM> may generate, by the second layer and based on the information, the message in the format for communicating with the neighboring UE.

In some aspects, communications manager <NUM> may select, at a UE that is configured to transmit a message to a neighboring UE via multiple protocols, one or more parameters indicative of a RAT to be used for the message. Communications manager <NUM> may convey information indicating the one or more parameters from a first layer of the UE to a second layer of the UE, where the first layer is an upper layer with respect to the second layer. Communications manager <NUM> may instantiate, by the second layer and based on the parameter, a channel for communications with the neighboring UE according to the RAT.

In some aspects, communications manager <NUM> may determine that the UE supports communicating using a first format and a second format, the first format being a legacy format with respect to the second format. Communications manager <NUM> may receive one or more messages from one or more neighboring UEs. Communications manager <NUM> may determine, based on the one or more messages, that the one or more neighboring UEs support communications using the second format. Communications manager <NUM> may select the second format for communications with the one or more neighboring UEs.

<FIG> shows a block diagram <NUM> of a wireless device <NUM> that supports eV2X RAT migration, in accordance with one or more aspects of the present disclosure. Wireless device <NUM> may be an example of aspects of a wireless device <NUM> or a UE <NUM> as described herein. Wireless device <NUM> may include receiver <NUM>, communications manager <NUM>, and transmitter <NUM>. Wireless device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

Communications manager <NUM> may be an example of aspects of the communications manager <NUM> described with reference to <FIG>. Communications manager <NUM> may also include parameter manager <NUM>, indication manager <NUM>, and generation manager <NUM>.

Parameter manager <NUM> may identify, at a UE that is configured to transmit a message to a neighboring UE via multiple formats, a service parameter indicative of a format to be used for the message. Parameter manager <NUM> may select, at a UE that is configured to transmit a message to a neighboring UE via multiple protocols, one or more parameters indicative of a RAT to be used for the message. Parameter manager <NUM> may determine that the UE supports communicating using a first format and a second format, the first format being a legacy format with respect to the second format. Parameter manager <NUM> may determine, based on the one or more messages, that the one or more neighboring UEs support communications using the second format. In some cases, the second format includes a RAN Release <NUM> or a RAN Release <NUM> format and the first format includes a RAN Release <NUM> format.

Indication manager <NUM> may convey information indicating the service parameter from a first layer of the UE to a second layer of the UE, where the first layer is an upper layer with respect to the second layer. Indication manager <NUM> may convey information indicating the one or more parameters from a first layer of the UE to a second layer of the UE, where the first layer is an upper layer with respect to the second layer, and receive one or more messages from one or more neighboring UEs.

Generation manager <NUM> may generate, by the second layer and based on the information, the message in the format for communicating with the neighboring UE. Generation manager <NUM> may instantiate, by the second layer and based on the parameter, a channel for communications with the neighboring UE according to the RAT. Generation manager <NUM> may instantiate an LTE channel for communications with the neighboring UE by default and set up a next generation NR channel dynamically based on receiving a message from the neighboring UE triggering the set up of the NR channel. Generation manager <NUM> may select the second format for communications with the one or more neighboring UEs. In some cases, generating the message includes: generating the message as a version of multiple versions of V2X messages.

<FIG> shows a block diagram <NUM> of a communications manager <NUM> that supports eV2X RAT migration, in accordance with one or more aspects of the present disclosure. The communications manager <NUM> may be an example of aspects of a communications manager <NUM>, a communications manager <NUM>, or a communications manager <NUM> described with reference to <FIG>, <FIG>, and <FIG>. The communications manager <NUM> may include parameter manager <NUM>, indication manager <NUM>, generation manager <NUM>, V2X communications manager <NUM>, flag manager <NUM>, classification manager <NUM>, QoS/PPP/L2 ID/PSID manager <NUM>, bearer manager <NUM>, and SA/header decoder <NUM>. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses).

V2X communications manager <NUM> may transmit the configured message to the neighboring UE according to the format. V2X communications manager <NUM> may access, by the first layer, either a preconfigured rule or a rule received from a network entity to select the one or more parameters. In some cases, the message is associated with a service, and where identifying the service parameter includes: selecting a service identifier associated with the service. In some cases, the service includes a cooperative adaptive cruise control service, a platooning operation service, or a sensor sharing service. In some cases, the communicating with the neighboring UE include communicating a safety message associated with vehicle-based operations. In some cases, the communication according to the RAT includes one or more of a supported broadcast traffic function, a safety message function, a scheduling assignment, a carrier aggregation, a MCS, and a TTI. In some cases, the communications with the neighboring UE include communicating a message associated with vehicle-based operations. In some cases, the one or more messages are associated with safety messages configured according to the first format. In some cases, the one or more messages include a service identifier, where the service identifier conveys an indication that the UE supports communications using the second format.

Flag manager <NUM> may include in the message, and by the first layer, a flag to indicate the service parameter. In some cases, including the flag includes: determining whether to include the flag in the message based on a listing of service identifiers associated with the format. Classification manager <NUM> may classify the message based at least on the service parameter.

QoS/PPP/L2 ID/PSID manager <NUM> may identify, by the first layer, one or more of a QoS metric, a PPPP, a service identifier, and an L2ID, associated with the communications with the neighboring UE, where the parameter includes one or more of the QoS metric, the PPPP, the service identifier, and the L2ID. QoS/PPP/L2 ID/PSID manager <NUM> may configure, for each packet of a one or more packets, the packet to indicate one or more of the QoS metric, the PPPP, the service identifier, and the L2ID, to the second layer. In some cases, the QoS metric is associated with a VQI.

Bearer manager <NUM> may configure, by the second layer and according to the parameter, a virtual bearer to use for communications with the UE. In some cases, the virtual bearer includes one or more aspects of a logical bearer and a radio bearer. In some cases, the virtual bearer includes at least one of a LTE V2X bearer and one or more next generation NR bearers, e.g., zero, one, or a group of NR bearers. In some cases, the one or more virtual NR bearers are instantiated dynamically by the second layer based on the parameters selected by the first layer. In some cases, the virtual bearer is configured based on a message received from the neighboring UE. In some cases, the receipt of the message triggers the activation of an application associated with the virtual bearer.

SA/header decoder <NUM> may decode, for each received message, a scheduling assignment to determine that the UE support communications using the second format. SA/header decoder <NUM> may decode, for each received message, a header portion of the message to determine that the UE support communications using the second format. In some cases, the header portion of the message includes a MAC header portion, a RLC header portion, or a PDCP header portion.

<FIG> shows a diagram of a system <NUM> including a device <NUM> that supports eV2X RAT migration, in accordance with one or more aspects of the present disclosure. Device <NUM> may be an example of or include the components of wireless device <NUM>, wireless device <NUM>, or a UE <NUM> as described herein. Device <NUM> may include components for bidirectional voice and data communications including components for transmitting and receiving communications, including communications manager <NUM>, processor <NUM>, memory <NUM>, software <NUM>, transceiver <NUM>, antenna <NUM>, and I/O controller <NUM>. These components may be in electronic communication via one or more buses (e.g., bus <NUM>). Device <NUM> may communicate wirelessly with one or more base stations <NUM>.

Processor <NUM> may include an intelligent hardware device, (e.g., a general-purpose processor, a DSP, a central processing unit (CPU), a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, processor <NUM> may be configured to operate a memory array using a memory controller. In other cases, a memory controller may be integrated into processor <NUM>. Processor <NUM> may be configured to execute computer-readable instructions stored in a memory to perform various functions (e.g., functions or tasks supporting eV2X RAT migration).

Software <NUM> may include code to implement aspects of the present disclosure, including code to support eV2X RAT migration. Software <NUM> may be stored in a non-transitory computer-readable medium such as system memory or other memory. In some cases, the software <NUM> may not be directly executable by the processor but may cause a computer (e.g., when compiled and executed) to perform functions described herein.

<FIG> shows a flowchart illustrating a method <NUM> for eV2X RAT migration, in accordance with one or more aspects of the present disclosure. The operations of method <NUM> may be implemented by a UE <NUM> or its components as described herein. For example, the operations of method <NUM> may be performed by a communications manager as described with reference to <FIG>. In some examples, a UE <NUM> may execute a set of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the UE <NUM> may perform aspects of the functions described below using special-purpose hardware.

At block <NUM> the UE <NUM> may identify, at a UE that is configured to transmit a message to a neighboring UE via multiple formats, a service parameter indicative of a format to be used for the message. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by a parameter manager as described with reference to <FIG>.

At block <NUM> the UE <NUM> may convey information indicating the service parameter from a first layer of the UE to a second layer of the UE, wherein the first layer is an upper layer with respect to the second layer. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by an indication manager as described with reference to <FIG>.

At block <NUM> the UE <NUM> may generate, by the second layer and based at least in part on the information, the message in the format for communicating with the neighboring UE. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by a generation manager as described with reference to <FIG>.

At block <NUM> the UE <NUM> may select, at a UE that is configured to transmit a message to a neighboring UE via multiple protocols, one or more parameters indicative of a RAT to be used for the message. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by a parameter manager as described with reference to <FIG>.

At block <NUM> the UE <NUM> may convey information indicating the one or more parameters from a first layer of the UE to a second layer of the UE, wherein the first layer is an upper layer with respect to the second layer. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by an indication manager as described with reference to <FIG>.

At block <NUM> the UE <NUM> may instantiate, by the second layer and based at least in part on the parameter, a channel for communications with the neighboring UE according to the RAT. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by a generation manager as described with reference to <FIG>.

At block <NUM> the UE <NUM> may determine that the UE supports communicating using a first format and a second format, the first format being a legacy format with respect to the second format. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by a parameter manager as described with reference to <FIG>.

At block <NUM> the UE <NUM> may receive one or more messages from one or more neighboring UEs. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by an indication manager as described with reference to <FIG>.

At block <NUM> the UE <NUM> may determine, based at least in part on the one or more messages, that the one or more neighboring UEs support communications using the second format. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by a parameter manager as described with reference to <FIG>.

At block <NUM> the UE <NUM> may select the second format for communications with the one or more neighboring UEs. The operations of block <NUM> may be performed according to the methods described herein. In certain examples, aspects of the operations of block <NUM> may be performed by a generation manager as described with reference to <FIG>.

The terms "system" and "network" are often used interchangeably. A code division multiple access (CDMA) system may implement a radio technology such as CDMA2000, Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-<NUM>, IS-<NUM>, and IS-<NUM> standards.

In LTE/LTE-A networks, including such networks described herein, the term evolved node B (eNB) may be generally used to describe the base stations. The wireless communications system or systems described herein may include a heterogeneous LTE/LTE-A or NR network in which different types of eNBs provide coverage for various geographical regions. For example, each eNB, next generation NodeB (gNB), or base station may provide communication coverage for a macro cell, a small cell, or other types of cell. The term "cell" may be used to describe a base station, a carrier or component carrier associated with a base station, or a coverage area (e.g., sector, etc.) of a carrier or base station, depending on context.

Base stations may include or may be referred to by those skilled in the art as a base transceiver station, a radio base station, an access point, a radio transceiver, a NodeB, eNodeB (eNB), gNB, Home NodeB, a Home eNodeB, or some other suitable terminology. The geographic coverage area for a base station may be divided into sectors making up only a portion of the coverage area. The wireless communications system or systems described herein may include base stations of different types (e.g., macro or small cell base stations). The UEs described herein may be able to communicate with various types of base stations and network equipment including macro eNBs, small cell eNBs, gNBs, relay base stations, and the like. There may be overlapping geographic coverage areas for different technologies.

Each communication link described herein-including, for example, wireless communication system <NUM> of <FIG>-may include one or more carriers, where each carrier may be a signal made up of multiple sub-carriers (e.g., waveform signals of different frequencies).

Also, as used herein, including in the claims, "or" as used in a list of items (for example, a list of items prefaced by a phrase such as "at least one of' or "one or more of') indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C).

By way of example, and not limitation, non-transitory computer-readable media may comprise RAM, ROM, electrically erasable programmable read only memory (EEPROM), compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor.

Claim 1:
A method (<NUM>) for wireless communication, comprising:
identifying (<NUM>), at a user equipment, UE, that is configured to transmit a message to a first neighboring UE of one or more neighboring UEs via multiple formats, a service identifier of a safety message and indicative of a format to be used for the message, the multiple formats comprising formats of different radio access technologies, RATs, wherein a first format of the multiple formats comprises a legacy format with respect to a second format of the multiple formats;
conveying (<NUM>), information indicating the service identifier from a first layer of the UE to a second layer of the UE, wherein the first layer is an upper layer with respect to the second layer;
receiving one or more messages from the one or more neighboring UEs;
decoding, for each received message based on the service identifier being of a safety message, a scheduling assignment or a header portion of the message to determine that all the neighboring UEs support communications using the second format;
selecting the second format for communications with the neighboring UE when all the neighboring UEs support communications using the second format; and
generating (<NUM>), by the second layer based on the selecting, the message in the second format for communicating with the first neighboring UE of the one or more neighboring UEs.