WO2017136627A1

WO2017136627A1 - Efficient multicast broadcast transmission and reception

Info

Publication number: WO2017136627A1
Application number: PCT/US2017/016354
Authority: WO
Inventors: Martino M. Freda; Benoit Pelletier; Paul Marinier; Marian Rudolf
Original assignee: Interdigital Patent Holdings, Inc.
Priority date: 2016-02-03
Filing date: 2017-02-03
Publication date: 2017-08-10

Abstract

Systems, methods, and instrumentalities are disclosed for transmitting and/or receiving messages, such as vehicle-to-everything (V2X) messages. For example, a wireless transmit/receive unit (WTRU) may identify contextual information of the WTRU. The contextual information of the WTRU may include location, movement, and/or status information of the WTRU. The WTRU may receive a configuration. The configuration may include possible or selectable radio configuration parameters. The WTRU may determine a set of radio configuration parameters to utilize for transmission and/or reception from the possible radio configuration parameters. The determination of the set of radio configuration parameters may be based, at least in part, on the identified contextual information of the WTRU. The WTRU may configure the WTRU using the determined set of radio configuration parameters.

Description

EFFICIENT MULTICAST BROADCAST TRANSMISSION

AND RECEPTION

CROSS REFERENCE

[0001] This application claims the benefit of U.S. Provisional Application No.

62/290,732 filed on February 3, 2016, which is incorporated herein by reference as if fully set forth.

BACKGROUND

[0002] Device-to-device (D2D) communications may be utilized to allow for cost- efficient and high-capability public safety communications using long term evolution (LTE) technology. D2D communications may be used in vehicular communication systems. For example, D2D communications may be used in vehicular communication systems to avoid accidents and traffic congestions.

SUMMARY

[0003] Systems, methods, and instrumentalities are disclosed for sending and/or receiving transmissions using one or more transmission parameters that may be determined based on context information related to the transmitting and/or receiving device(s). For example, transmission parameters determined based on transmitter and/or receiver context information may be used when transmitting and/or receiving vehicle-to-everything (V2X)-type messages. A wireless transmit/receive unit (WTRU), for example, may identify contextual information of the WTRU. The WTRU may be a V2X WTRU that may identify contextual information of the V2X WTRU. The contextual information of the WTRU may include location, movement, and/or status information of the WTRU. The WTRU may receive a configuration. The configuration may include a set of possible or selectable radio configuration parameters that could be used for transmission and/or reception (e.g., such as V2X radio configuration parameters). The WTRU may determine a set of radio configuration parameters from the possible or selectable radio configuration parameters indicated in the configuration. The determination of the set of radio configuration parameters may be based, at least in part, on the identified contextual information of the WTRU. The WTRU may configure the WTRU using the determined set of radio configuration parameters. The WTRU may autonomously determine one or more other radio configuration parameters based on the context information independently from the received configuration.

[0004] The radio configuration parameters determined based on context information may include parameters used for the operation of the WTRU. For example, the radio configuration parameters determined based on context information may include parameters used by the WTRU for communication, power, status, etc. The radio configuration parameters determined based on context information may include a radio interface and/or mechanism. For example, the radio configuration parameters determined based on context information may include an indication of whether the WTRU may communicate via the PC5 interface and/or the Uu interface. The radio configuration parameters determined based on context information may include may include power control parameters of the WTRU. The radio configuration parameters determined based on context information may include transmission and/or reception parameters to be used by the WTRU. Transmission and/or reception parameters to be used by the WTRU may include one or more resource pools utilized by the WTRU, a number of resource blocks (RBs) supported for one or more transport blocks (TBs), a frequency that the WTRU may hop to/from, the set of time resource patterns (T-RPTs) supported, L2 group identities of the WTRU, the set of RNTIs to monitor for the WTRU, parameters related to sensing and/or channel-busy-ratio measurements, definition/configuration of one or more communication channels (e.g., scheduling assignment and data channels), enhanced multicast broadcast (eMBMS) parameters to be used by the WTRU, a priority in which messages will be processed by the WTRU, and/or a threshold battery level of the WTRU.

[0005] The radio configuration parameters determined based on context information may include an activation and/or deactivation status of the WTRU, a DRX and/or DTX configuration of the WTRU, transmission rate parameters of the WTRU, receiver (RX) and/or transmitter (TX) identities of the WTRU, message reception and/or processing rates of the WTRU, and/or message transmission rates of the WTRU.

[0006] The contextual information used to determine or derive the radio configuration parameters may correspond to information related to one or more WTRUs (e.g., the transmitting WTRU, the receiving WTRU, another WTRU, a V2X WTRU, etc.). The contextual information of a WTRU (e.g., a V2X WTRU or another WTRU) may be location information (e.g., absolute location information and/or relative location information) of the WTRU, movement information of the WTRU, status information of the WTRU, etc. For example, contextual information of a WTRU (e.g., a V2X WTRU or another WTRU) may include geographical location information of the WTRU or of another WTRU. Contextual information of a WTRU may include speed, direction of heading, altitude, and/or acceleration information of the WTRU or of another WTRU.

[0007] Contextual information of a WTRU may include status information of the WTRU, status information of the user of the WTRU (e.g., a pedestrian or driver using a V2X-type WTRU), and/or status information of another WTRU. Contextual information of a WTRU may include a proximity to a street or intersection, for example, when the WTRU is a V2X WTRU. Contextual information of a WTRU may include an in-building indication of the WTRU or of another WTRU. Contextual information of a WTRU may include an in-car indication of the WTRU or of another WTRU. Contextual information of a WTRU may include a proximity of the WTRU or another WTRU to a specific area, reference point or landmark. Contextual information of a WTRU may include an indication of whether the WTRU or another WTRU is on a non-car street vehicle. Contextual information of a WTRU may include a level of risk and/or danger of the WTRU. For example, contextual information of a WTRU may include a level of risk and/or danger of the WTRU, based on one or more of the above information. Contextual information of a WTRU may include a WTRU battery power indication and/or a user interaction indication of the WTRU.

[0008] A WTRU, such as a V2X WTRU, may be configured to receive and/or process broadcast transmissions and the processing may be based on context information associated with the WTRU. For example, a WTRU may be configured to receive and/or process broadcast transmissions being sent by transmitters in an area and/or location of interest to the receiving WTRU.

[0009] Group radio network temporary identifiers (RNTIs) may be mapped to a predefined location and/or group RNTIs may be mapped to a predefined distance from a location.

[0010] A multicast traffic channel (MTCH) may be mapped to a predefined location. A PC5 resource pool may be mapped to a predefined location.

[0011] A WTRU configured to receive broadcast transmissions may receive and/or process broadcast transmissions being sent by transmitters with a predefined or known speed, direction, and/or acceleration characteristics. For example, a V2X WTRU configured to receive broadcast transmissions may receive and/or process broadcast transmissions being sent by one or more V2X-type transmitters with a predefined or known speed, direction, and/or acceleration characteristics

[0012] A WTRU may be configured to determine when to start monitoring for certain types of messages. For example, a WTRU may be configured to determine when to start monitoring for certain types of messages based on context information. As an example, a V2X WTRU may be configured to determine when to start monitoring for V2P messages. For example, a V2X WTRU may be configured to determine when to start monitoring for V2P messages, based on context.

[0013] A WTRU may be configured to determine a priority of messages to process. For example, a WTRU may be configured to determine a priority of messages to process, based on context (e.g., battery power).

[0014] A WTRU may be configured to modify a sleep cycle and/or message processing frequency of the WTRU. For example, a V2X WTRU may be configured to modify a sleep cycle and/or message processing frequency of the WTRU when receiving a message and/or changing a location.

[0015] A WTRU may be configured to transmit on behalf of a crowd of WTRUs.

[0016] A WTRU may change (e.g., dynamically change) between transmission over Uu, and/or PC5. The WTRU may change between transmission over Uu, and/or PC5, based on context and/or configuration. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] A more detailed understanding may be had from the following description, given by way of example in conjunction with the accompanying drawings wherein:

[0018] FIG. 1 A is a system diagram of an example communications system in which one or more disclosed embodiments may be implemented;

[0019] FIG. IB is a system diagram of an example wireless transmit/receive unit (WTRU) that may be used within the communications system illustrated in FIG. 1 A;

[0020] FIG. 1C is a system diagram of an example radio access network and an example core network that may be used within the communications system illustrated in FIG. 1 A;

[0021] FIG ID is a system diagram of another example radio access network and an example core network that may be used within the communications system illustrated in FIG. 1A;

[0022] FIG. IE is a system diagram of another example radio access network and an example core network that may be used within the communications system illustrated in FIG. 1A;

[0023] FIG. 2 depicts an example cell area subdivided into locations;

[0024] FIG. 3 shows an example WTRU that may broadcast messages destined for a WTRU using the Uu interface.

[0025] FIG. 4 shows an example WTRU that may broadcast messages destined for a WTRU using the PC5 interface.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0026] A detailed description of illustrative embodiments will now be described with reference to the various Figures. Although this description provides a detailed example of possible implementations, it should be noted that the details are intended to be exemplary and in no way limit the scope of the application.

[0027] Communication schemes may be developed for vehicular communications. The communication schemes may rely on transmissions that are relatively short messages, that rely on a relatively high reliability at the access stratum (AS) level, and/or that expect relatively low latency to support specific uses. For example, vehicle communication requirements, such as vehicle-to-everything (V2X) communication requirements, may call for transmissions of short messages, high reliability at the AS level, and/or low latency to support forward collision warning, control loss warning, and/or emergency stops. When used herein the term V2X may be used to refer to one or more communications that in some way support a vehicular

communication scheme. However, the devices exchanging V2X messages may not necessarily be vehicles themselves (e.g., cars, trains, drones, etc.). For example, wireless communication devices associated with pedestrians (e.g., pedestrians in the vicinity of a vehicle; a pedestrian WTRU; etc.) may transmit and/or receive V2X messages. A roadside unit (RSU) may be a communication device that transmits V2X messages to support vehicular communications. For example, RSUs may transmit V2X messages relating to traffic events in the vicinity of the RSU. Any of these communications to support any type of vehicular and/or transportation related applications may be generically referred to as V2X messages herein.

[0028] For example, V2X communications, such as vehicle-to-pedestrian (V2P) communications, may be used to warn one or more WTRUs against one or more collisions. For example, V2X (e.g., V2P) communications may be used to warn one or more pedestrian WTRUs against one or more pedestrian collisions. For example, warnings may be provided to a pedestrian WTRU to avoid a possible collision with a vehicle. Communications, such as V2P, may be used for vulnerable road user safety. For example, a vehicle may detect a pedestrian presence and inform the driver. Communications, such as V2P, may be used for pedestrian road safety via V2P awareness messages, for example. A pedestrian may transmit basic awareness messages to vehicles which may perform collision risk assessment and/or inform the driver if a risk of collision may exist.

[0029] A WTRU, such as a pedestrian WTRU, may transmit warning and/or awareness messages to vehicles. For example, a pedestrian WTRU may periodically transmit warning and/or awareness messages to surrounding vehicles. Having such transmissions occur on a regular basis may result in a larger than needed power consumption. It may be desirable to reduce the transmission overhead of the pedestrian WTRU while maintaining requirements of a service, such as a V2P service. Dynamic and/or contextual configuration of radio communication parameters may improve power/efficiency of communications. For example, dynamic and/or contextual configuration of V2X radio communication parameters may improve

power/efficiency of V2P/P2V communications

[0030] A WTRU may be configured with radio configuration parameters that may be associated with contextual information. For example, a V2X WTRU may be configured with V2x radio configuration parameters that may be associated with contextual information. The radio configuration parameters may include parameters used for the operation of the WTRU. For example, the radio configuration parameters may include parameters used by the WTRU for communication, power, status, etc., of the WTRU. The radio configuration parameters may include a radio interface/mechanism. A radio interface/mechanism may include a

communication via one or more of the PC5 interface, Uu interface, and/or other radio interface. The radio configuration parameters may include power control parameters.

[0031] The radio configuration parameters may include transmission/reception configuration parameters. For example, the V2X radio configuration parameters may include transmission/reception configuration parameters. Transmission/reception configuration parameters may include resource pool(s). Transmission/reception configuration parameters may include the modulation and coding scheme (MCS), the number of resource blocks (RBs) for each transport block (TB) supported, etc. Transmission/reception configuration parameters may include frequency hopping configuration. Transmission/reception configuration parameters may include a set of time resource patterns (T-RPTs) supported. Transmission/reception

configuration parameters may include L2 group identities. Transmission/reception configuration parameters may include a set of radio network temporary identifiers (RNTIs) to monitor. For example, transmission/reception configuration parameters may include a set of radio network temporary identifiers (RNTIs) to monitor for PC5 interface scheduling, SC-PTM, DCI monitoring, etc. Transmission/reception configuration parameters may include eMBMS parameters (e.g. temporary mobile group identity (TMGI)) to monitor, etc.

Transmission/reception configuration parameters may include a priority of processed message. Transmission/reception configuration parameters may include a threshold battery level.

[0032] The radio configuration parameters may include a parameter configuration. For example, the V2X radio configuration parameters may include a V2X parameter configuration. A parameter configuration may include an activation/deactivation status. A parameter configuration may include a DRX configuration. A parameter configuration may include a DTX configuration. A parameter configuration may include transmission rate parameters. A parameter configuration may include RX/TX Identities. A parameter configuration may include a message reception/processing rate and/or periodicity. A parameter configuration may include a message transmission rate and/or periodicity.

[0033] A WTRU (e.g., a WTRU supporting V2X) may be configured with one or more sets of radio configuration parameters, such as one or more sets of V2X radio configuration parameters. For example, the WTRU may be configured with one or more sets of radio configuration parameters which may be associated with contextual information. The associated contextual information may be information related to one or more WTRUs (e.g., a V2X WTRU or another WTRU). The contextual information of a WTRU (e.g., a V2X WTRU or another WTRU) may be location information (e.g., absolute location information and/or relative location information) of the WTRU, movement information of the WTRU, status information of the WTRU, etc.

[0034] Contextual information associated with a set of configuration parameters may include geographical location of the WTRU and/or contextual information associated with a set of configuration parameters may include geographical location of another WTRU. For example, the contextual information associated with a set of configuration parameters may include a longitude, latitude, and/or elevation; in a range of the longitude, latitude, and/or elevation; and/or with respect to a known reference point of the WTRU itself and/or of another WTRU. The contextual information associated with a set of configuration parameters may include speed, direction of heading, and/or acceleration of the WTRU itself and/or of another WTRU. The contextual information associated with a set of configuration parameters may include status of the WTRU itself, of the pedestrian using the WTRU, and/or of another WTRU (e.g., vehicle and/or other). The contextual information associated with a set of configuration parameters may include proximity to street indication of the WTRU itself and/or of another WTRU (e.g., vehicle and/or other).

[0035] The contextual information associated with a set of configuration parameters may include an in-building indication. The contextual information associated with a set of configuration parameters may include an in-car indication. The contextual information associated with a set of configuration parameters may include an indication of proximity to a specific area and/or landmark. For example, the contextual information associated with a set of configuration parameters may include an in parking lot indication. The contextual information associated with a set of configuration parameters may include an on motorcycle/bicycle or other non-car street vehicular indication. The contextual information associated with a set of configuration parameters may include a level of risk/danger based on any or a combination of the information provided herein. The contextual information associated with a set of configuration parameters may include a WTRU battery power (e.g., compared to a configured threshold). The contextual information associated with a set of configuration parameters may include a user interaction.

[0036] Although many of the examples described herein may be described with respect to V2X communications, the techniques described in these examples may also be applicable to other types of communications. For example, transmission techniques that utilize transmitter and/or receiver contextual information to determine one or more transmission settings may be used to support V2X communications or other types of communications. An example of another type of application may be an Internet of Things (IoT) type application. For example, an IoT device performing transmission and/or reception of an IoT-type communication may utilize one or more of the techniques described herein with respect to a V2X device or V2X WTRU. Thus, examples described herein with respect to V2X WTRUs may also be implemented by non-V2X WTRUs, for example to support other types of applications.

[0037] FIG. 1 A is a diagram of an example communications system 100 in which one or more disclosed embodiments may be implemented. The communications system 100 may be a multiple access system that provides content, such as voice, data, video, messaging, broadcast, etc., to multiple wireless users. The communications system 100 may enable multiple wireless users to access such content through the sharing of system resources, including wireless bandwidth. For example, the communications systems 100 may employ one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single- carrier FDMA (SC-FDMA), and the like.

[0038] As shown in FIG. 1 A, the communications system 100 may include wireless transmit/receive units (WTRUs) 102a, 102b, 102c, and/or 102d (which generally or collectively may be referred to as WTRU 102), a radio access network (RAN) 103/104/105, a core network 106/107/109, a public switched telephone network (PSTN) 108, the Internet 110, and other networks 112, though it will be appreciated that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and/or network elements. Each of the WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and/or communicate in a wireless environment. By way of example, the WTRUs 102a, 102b, 102c, 102d may be configured to transmit and/or receive wireless signals and may include user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a pager, a cellular telephone, a personal digital assistant (PDA), a smartphone, a laptop, a netbook, a personal computer, a wireless sensor, consumer electronics, and the like.

[0039] The communications systems 100 may also include a base station 114a and a base station 114b. Each of the base stations 114a, 114b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as the core network 106/107/109, the Internet 110, and/or the networks 112. By way of example, the base stations 114a, 114b may be a base transceiver station (BTS), a Node-B, an eNode B, a Home Node B, a Home eNode B, a site controller, an access point (AP), a wireless router, and the like. While the base stations 114a, 114b are each depicted as a single element, it will be appreciated that the base stations 114a, 114b may include any number of interconnected base stations and/or network elements.

[0040] The base station 114a may be part of the RAN 103/104/105, which may also include other base stations and/or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), relay nodes, etc. The base station 114a and/or the base station 114b may be configured to transmit and/or receive wireless signals within a particular geographic region, which may be referred to as a cell (not shown). The cell may further be divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three sectors. Thus, in one embodiment, the base station 114a may include three transceivers, i.e., one for each sector of the cell. In another embodiment, the base station 114a may employ multiple-input multiple output (MTMO) technology and, therefore, may utilize multiple transceivers for each sector of the cell.

[0041] The base stations 114a, 114b may communicate with one or more of the WTRUs 102a, 102b, 102c, 102d over an air interface 115/116/117, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 115/116/117 may be established using any suitable radio access technology (RAT).

[0042] More specifically, as noted above, the communications system 100 may be a multiple access system and may employ one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and the like. For example, the base station 114a in the RAN 103/104/105 and the WTRUs 102a, 102b, 102c may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may establish the air interface 115/116/117 using wideband CDMA (WCDMA).

WCDMA may include communication protocols such as High-Speed Packet Access (HSPA) and/or Evolved HSPA (HSPA+). HSPA may include High-Speed Downlink Packet Access (HSDPA) and/or High-Speed Uplink Packet Access (HSUPA).

[0043] In another embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 115/116/117 using Long Term Evolution (LTE) and/or LTE-Advanced (LTE-A).

[0044] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement radio technologies such as IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 IX, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), and the like.

[0045] The base station 114b in FIG. 1 A may be a wireless router, Home Node B, Home eNode B, or access point, for example, and may utilize any suitable RAT for facilitating wireless connectivity in a localized area, such as a place of business, a home, a vehicle, a campus, and the like. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In another embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In yet another embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular- based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, etc.) to establish a picocell or femtocell. As shown in FIG. 1 A, the base station 114b may have a direct connection to the Internet 110. Thus, the base station 114b may not be required to access the Internet 110 via the core network 106/107/109.

[0046] The RAN 103/104/105 may be in communication with the core network

106/107/109, which may be any type of network configured to provide voice, data, applications, and/or voice over internet protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. For example, the core network 106/107/109 may provide call control, billing services, mobile location-based services, pre-paid calling, Internet connectivity, video distribution, etc., and/or perform high-level security functions, such as user authentication.

Although not shown in FIG. 1 A, it will be appreciated that the RAN 103/104/105 and/or the core network 106/107/109 may be in direct or indirect communication with other RANs that employ the same RAT as the RAN 103/104/105 or a different RAT. For example, in addition to being connected to the RAN 103/104/105, which may be utilizing an E-UTRA radio technology, the core network 106/107/109 may also be in communication with another RAN (not shown) employing a GSM radio technology.

[0047] The core network 106/107/109 may also serve as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and/or other networks 112. The PSTN 108 may include circuit-switched telephone networks that provide plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols, such as the transmission control protocol (TCP), user datagram protocol (UDP) and the internet protocol (IP) in the TCP/IP internet protocol suite. The networks 112 may include wired or wireless

communications networks owned and/or operated by other service providers. For example, the networks 112 may include another core network connected to one or more RANs, which may employ the same RAT as the RAN 103/104/105 or a different RAT.

[0048] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communications system 100 may include multi-mode capabilities, i.e., the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks over different wireless links. For example, the WTRU 102c shown in FIG. 1 A may be configured to communicate with the base station 114a, which may employ a cellular-based radio technology, and with the base station 114b, which may employ an IEEE 802 radio technology. [0049] FIG. IB is a system diagram of an example WTRU 102. As shown in FIG. IB, the WTRU 102 may include a processor 118, a transceiver 120, a transmit/receive element 122, a speaker/microphone 124, a keypad 126, a display/touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a global positioning system (GPS) chipset 136, and other peripherals 138. It will be appreciated that the WTRU 102 may include any subcombination of the foregoing elements while remaining consistent with an embodiment. Also, embodiments contemplate that the base stations 114a and 114b, and/or the nodes that base stations 114a and 114b may represent, such as but not limited to transceiver station (BTS), a Node-B, a site controller, an access point (AP), a home node-B, an evolved home node-B (eNodeB), a home evolved node-B (HeNB), a home evolved node-B gateway, and proxy nodes, among others, may include some or all of the elements depicted in FIG. IB and described herein.

[0050] The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of

microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, Application Specific Integrated Circuits (ASICs), Field Programmable Gate Array (FPGAs) circuits, any other type of integrated circuit (IC), a state machine, and the like. The processor 118 may perform signal coding, data processing, power control, input/output processing, and/or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit/receive element 122. While FIG. IB depicts the processor 118 and the transceiver 120 as separate components, it will be appreciated that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0051] The transmit/receive element 122 may be configured to transmit signals to, or receive signals from, a base station (e.g., the base station 114a) over the air interface

115/116/117. For example, in one embodiment, the transmit/receive element 122 may be an antenna configured to transmit and/or receive RF signals. In another embodiment, the transmit/receive element 122 may be an emitter/detector configured to transmit and/or receive IR, UV, or visible light signals, for example. In yet another embodiment, the transmit/receive element 122 may be configured to transmit and receive both RF and light signals. It will be appreciated that the transmit/receive element 122 may be configured to transmit and/or receive any combination of wireless signals. [0052] In addition, although the transmit/receive element 122 is depicted in FIG. IB as a single element, the WTRU 102 may include any number of transmit/receive elements 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit/receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface 115/116/117.

[0053] The transceiver 120 may be configured to modulate the signals that are to be transmitted by the transmit/receive element 122 and to demodulate the signals that are received by the transmit/receive element 122. As noted above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs, such as UTRA and IEEE 802.11, for example.

[0054] The processor 118 of the WTRU 102 may be coupled to, and may receive user input data from, the speaker/microphone 124, the keypad 126, and/or the display/touchpad 128 (e.g., a liquid crystal display (LCD) display unit or organic light-emitting diode (OLED) display unit). The processor 118 may also output user data to the speaker/microphone 124, the keypad 126, and/or the display/touchpad 128. In addition, the processor 118 may access information from, and store data in, any type of suitable memory, such as the non-removable memory 130 and/or the removable memory 132. The non-removable memory 130 may include random- access memory (RAM), read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In other embodiments, the processor 118 may access information from, and store data in, memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0055] The processor 118 may receive power from the power source 134, and may be configured to distribute and/or control the power to the other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry cell batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, and the like.

[0056] The processor 118 may also be coupled to the GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to, or in lieu of, the information from the GPS chipset 136, the WTRU 102 may receive location information over the air interface 115/116/117 from a base station (e.g., base stations 114a, 114b) and/or determine its location based on the timing of the signals being received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information by way of any suitable location-determination method while remaining consistent with an embodiment.

[0057] The processor 118 may further be coupled to other peripherals 138, which may include one or more software and/or hardware modules that provide additional features, functionality and/or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an e-compass, a satellite transceiver, a digital camera (for photographs or video), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands free headset, a Bluetooth® module, a frequency modulated (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, and the like.

[0058] FIG. 1C is a system diagram of the RAN 103 and the core network 106 according to an embodiment. As noted above, the RAN 103 may employ a UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 115. The RAN 103 may also be in communication with the core network 106. As shown in FIG. 1C, the RAN 103 may include Node-Bs 140a, 140b, 140c, which may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 115. The Node-Bs 140a, 140b, 140c may each be associated with a particular cell (not shown) within the RAN 103. The RAN 103 may also include RNCs 142a, 142b. It will be appreciated that the RAN 103 may include any number of Node-Bs and RNCs while remaining consistent with an embodiment.

[0059] As shown in FIG. 1C, the Node-Bs 140a, 140b may be in communication with the RNC 142a. Additionally, the Node-B 140c may be in communication with the RNC 142b. The Node-Bs 140a, 140b, 140c may communicate with the respective RNCs 142a, 142b via an Iub interface. The RNCs 142a, 142b may be in communication with one another via an lur interface. Each of the RNCs 142a, 142b may be configured to control the respective Node-Bs 140a, 140b, 140c to which it is connected. In addition, each of the RNCs 142a, 142b may be configured to carry out or support other functionality, such as outer loop power control, load control, admission control, packet scheduling, handover control, macrodiversity, security functions, data encryption, and the like. [0060] The core network 106 shown in FIG. 1C may include a media gateway (MGW) 144, a mobile switching center (MSC) 146, a serving GPRS support node (SGSN) 148, and/or a gateway GPRS support node (GGSN) 150. While each of the foregoing elements are depicted as part of the core network 106, it will be appreciated that any one of these elements may be owned and/or operated by an entity other than the core network operator.

[0061] The RNC 142a in the RAN 103 may be connected to the MSC 146 in the core network 106 via an IuCS interface. The MSC 146 may be connected to the MGW 144. The MSC 146 and the MGW 144 may provide the WTRUs 102a, 102b, 102c with access to circuit- switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices.

[0062] The RNC 142a in the RAN 103 may also be connected to the SGSN 148 in the core network 106 via an IuPS interface. The SGSN 148 may be connected to the GGSN 150. The SGSN 148 and the GGSN 150 may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between and the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0063] As noted above, the core network 106 may also be connected to the networks 112, which may include other wired or wireless networks that are owned and/or operated by other service providers.

[0064] FIG. ID is a system diagram of the RAN 104 and the core network 107 according to an embodiment. As noted above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the core network 107.

[0065] The RAN 104 may include eNode-Bs 160a, 160b, 160c, though it will be appreciated that the RAN 104 may include any number of eNode-Bs while remaining consistent with an embodiment. The eNode-Bs 160a, 160b, 160c may each include one or more

transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the eNode-Bs 160a, 160b, 160c may implement MFMO technology. Thus, the eNode-B 160a, for example, may use multiple antennas to transmit wireless signals to, and receive wireless signals from, the WTRU 102a.

[0066] Each of the eNode-Bs 160a, 160b, 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the uplink and/or downlink, and the like. As shown in FIG. ID, the eNode-Bs 160a, 160b, 160c may communicate with one another over an X2 interface.

[0067] The core network 107 shown in FIG. ID may include a mobility management gateway (MME) 162, a serving gateway 164, and a packet data network (PDN) gateway 166. While each of the foregoing elements are depicted as part of the core network 107, it will be appreciated that any one of these elements may be owned and/or operated by an entity other than the core network operator.

[0068] The MME 162 may be connected to each of the eNode-Bs 160a, 160b, 160c in the RAN 104 via an SI interface and may serve as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, bearer

activation/deactivation, selecting a particular serving gateway during an initial attach of the WTRUs 102a, 102b, 102c, and the like. The MME 162 may also provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM or WCDMA.

[0069] The serving gateway 164 may be connected to each of the eNode-Bs 160a, 160b, 160c in the RAN 104 via the SI interface. The serving gateway 164 may generally route and forward user data packets to/from the WTRUs 102a, 102b, 102c. The serving gateway 164 may also perform other functions, such as anchoring user planes during inter-eNode B handovers, triggering paging when downlink data is available for the WTRUs 102a, 102b, 102c, managing and storing contexts of the WTRUs 102a, 102b, 102c, and the like.

[0070] The serving gateway 164 may also be connected to the PDN gateway 166, which may provide the WTRUs 102a, 102b, 102c with access to packet- switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0071] The core network 107 may facilitate communications with other networks. For example, the core network 107 may provide the WTRUs 102a, 102b, 102c with access to circuit- switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. For example, the core network 107 may include, or may communicate with, an IP gateway (e.g., an IP multimedia subsystem (IMS) server) that serves as an interface between the core network 107 and the PSTN 108. In addition, the core network 107 may provide the WTRUs 102a, 102b, 102c with access to the networks 112, which may include other wired or wireless networks that are owned and/or operated by other service providers.

[0072] FIG. IE is a system diagram of the RAN 105 and the core network 109 according to an embodiment. The RAN 105 may be an access service network (ASN) that employs IEEE 802.16 radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 117. As will be further discussed below, the communication links between the different functional entities of the WTRUs 102a, 102b, 102c, the RAN 105, and the core network 109 may be defined as reference points.

[0073] As shown in FIG. IE, the RAN 105 may include base stations 180a, 180b, 180c, and an ASN gateway 182, though it will be appreciated that the RAN 105 may include any number of base stations and ASN gateways while remaining consistent with an embodiment. The base stations 180a, 180b, 180c may each be associated with a particular cell (not shown) in the RAN 105 and may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 117. In one embodiment, the base stations 180a, 180b, 180c may implement MIMO technology. Thus, the base station 180a, for example, may use multiple antennas to transmit wireless signals to, and receive wireless signals from, the WTRU 102a. The base stations 180a, 180b, 180c may also provide mobility management functions, such as handoff triggering, tunnel establishment, radio resource management, traffic classification, quality of service (QoS) policy enforcement, and the like. The ASN gateway 182 may serve as a traffic aggregation point and may be responsible for paging, caching of subscriber profiles, routing to the core network 109, and the like.

[0074] The air interface 117 between the WTRUs 102a, 102b, 102c and the RAN 105 may be defined as an Rl reference point that implements the IEEE 802.16 specification. In addition, each of the WTRUs 102a, 102b, 102c may establish a logical interface (not shown) with the core network 109. The logical interface between the WTRUs 102a, 102b, 102c and the core network 109 may be defined as an R2 reference point, which may be used for

authentication, authorization, IP host configuration management, and/or mobility management.

[0075] The communication link between each of the base stations 180a, 180b, 180c may be defined as an R8 reference point that includes protocols for facilitating WTRU handovers and the transfer of data between base stations. The communication link between the base stations 180a, 180b, 180c and the ASN gateway 182 may be defined as an R6 reference point. The R6 reference point may include protocols for facilitating mobility management based on mobility events associated with each of the WTRUs 102a, 102b, 102c.

[0076] As shown in FIG. IE, the RAN 105 may be connected to the core network 109. The communication link between the RAN 105 and the core network 109 may defined as an R3 reference point that includes protocols for facilitating data transfer and mobility management capabilities, for example. The core network 109 may include a mobile IP home agent (M P-HA) 184, an authentication, authorization, accounting (AAA) server 186, and a gateway 188. While each of the foregoing elements are depicted as part of the core network 109, it will be appreciated that any one of these elements may be owned and/or operated by an entity other than the core network operator.

[0077] The MTP-HA may be responsible for IP address management, and may enable the WTRUs 102a, 102b, 102c to roam between different ASNs and/or different core networks. The MIP-HA 184 may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The AAA server 186 may be responsible for user authentication and for supporting user services. The gateway 188 may facilitate interworking with other networks. For example, the gateway 188 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. In addition, the gateway 188 may provide the WTRUs 102a, 102b, 102c with access to the networks 112, which may include other wired or wireless networks that are owned and/or operated by other service providers.

[0078] Although not shown in FIG. IE, it will be appreciated that the RAN 105 may be connected to other ASNs and the core network 109 may be connected to other core networks. The communication link between the RAN 105 the other ASNs may be defined as an R4 reference point, which may include protocols for coordinating the mobility of the WTRUs 102a, 102b, 102c between the RAN 105 and the other ASNs. The communication link between the core network 109 and the other core networks may be defined as an R5 reference, which may include protocols for facilitating interworking between home core networks and visited core networks. [0079] In view of Figures 1 A-1E, and the corresponding description of Figures 1 A-1E, one or more, or all, of the functions described herein with regard to one or more of: WTRU 102a-d, Base Station 114a-b, Node B 140a-c, RNC 142a-b, MSC 146, SGSN 148, MGW 144, CGSN 150, eNode-B 160a-c, MME 162, Serving Gateway 164, PDN Gateway 166, Base Station 180a-c, ASN Gateway 182, AAA 186, MIP-HA 184, Gateway 188, and/or any other device(s) described herein, may be performed by one or more emulation devices (not shown) (e.g., one or more devices configured to emulate one or more, or all, of the functions described herein).

[0080] The one or more emulation devices may be configured to perform the one or more, or all, functions in one or more modalities. The emulation devices may be designed to implement one or more tests of other devices. For example, the one or more emulation devices may perform the one or more, or all, functions while being fully or partially implemented and/or deployed as part of a wired and/or wireless communication network in order to test other devices within the communication network. The one or more emulation devices may perform the one or more, or all, functions while being temporarily implemented/deployed as part of a wired and/or wireless communication network. The emulation device may be directly coupled to another device for purposes of testing.

[0081] The one or more emulation devices may perform the one or more, including all, functions while not being implemented/deployed as part of a wired and/or wireless

communication network. For example, the emulation devices may be utilized in a testing scenario in a testing laboratory and/or a non-deployed (e.g. testing) wired and/or wireless communication network in order to implement testing of one or more components. The one or more emulation devices may be test equipment. Direct radio frequency (RF) coupling and/or wireless communications via RF circuitry (e.g., which may include one or more antennas) may be used by the emulation devices to transmit and/or receive data.

[0082] Networks may contain one or more types of nodes. For example, vehicular networks may contain vehicles and/or roadside stations. Vehicles and/or roadside stations may include dedicated short-range communications (DSRC) devices. A set of standards may be developed to support DSRC. Spectrum may be allocated to support DSRC. For example, spectrum may be allocated in the 5.9 GHz band with bandwidth of 75 MHz in the United States to support DSRC. Communication in the range of 1000m may be targeted to support DSRC. [0083] A standard for communications may be created. For example, a standard for vehicular communications may be created (e.g., may be created by adapting current LTE specifications). Vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), and vehicle-to- pedestrian (V2P) communications may be defined, for example, by adapting the current LTE specifications. V2V communications using the existing device-to-device (ProSe) framework may be considered.

[0084] Communication requirements may be developed. For example, communication requirements may be developed for vehicular communications. Vehicle-to-everything (V2X) communication requirements may be developed for vehicular communications. V2X may refer to one or more communications to, or from, a vehicle with a wireless communication device, such as V2V, V2P, V2I communications and/or the like. Communication requirements, such as V2X communication requirements, may call for transmission of short messages. For example, the communication requirements may call for transmission of messages on the order of 50 to several hundred bytes. Communication requirements may call for transmissions with high reliability at the access stratum (AS) level (e.g., up to 90%). Communication requirements may call for transmission with low latency. For example, the V2X communication requirements may call for transmission with latency as small as 100ms, 20ms, etc. Communication requirements may call for transmissions of short messages, high reliability at the AS level, and/or low latency to support specific uses. For example, V2X communication requirements may call for transmissions of short messages, high reliability at the AS level, and/or low latency to support forward collision warning, control loss warning, and/or emergency stops.

[0085] Support for device-to-device (D2D) communications may be introduced to allow for cost-efficient and/or high-capability public safety communications. For example, support for D2D communications may be introduced to allow for cost-efficient and/or high-capability public safety communications using LTE technology in the case of 3 GPP and LTE based radio access. Cost-efficient and/or high-capability public safety communications using LTE technology may harmonize the radio access technology across jurisdictions. For example, cost-efficient and/or high-capability public safety communications using LTE technology may lower the capital expenditures (CAPEX) and/or operational expenditure (OPEX) of radio-access technology available for the use of public safety (PS) type of applications. Cost-efficient and/or high- capability public safety communications using LTE technology may be motivated because LTE as a scalable wideband radio solution may allow for efficient multiplexing of one or more services types, such voice and/or video.

[0086] Public safety (PS) applications may require radio communications in areas that may not be under radio coverage of an LTE network. For example, PS applications may require radio communications in tunnels, in deep basements, and/or following catastrophic system outages. There may be a need to support D2D communications for PS in the absence of an operating network and/or prior to the arrival of AdHoc deployed radio infrastructure. For example, when operating in the presence of operating network infrastructure, PS

communications may require higher reliability than commercial services.

[0087] PS types of applications may include direct push-to-talk speech services using multiple talk groups. For example, PS types of applications between first responders may include direct push-to-talk speech services using multiple talk groups. PS types of applications may include services to make efficient use of the capabilities of an LTE broadband radio. For example, PS types of applications may include video push and/or download to make efficient use of the capabilities of an LTE broadband radio.

[0088] D2D communications may be available for PS types of applications and/or for commercial uses. For example, D2D communications may be available for users (e.g., utility companies) who require support for 2-way radio communications in areas not covered by network infrastructure. D2D services, such as discovery services, may be suitable signaling mechanisms to allow for proximity based services and/or traffic offload using LTE based radio access in commercial uses.

[0089] A V2V operation may be based on a PC5 interface. The PC5 interface may be a D2D communication interface. The PC5 interface may be a D2D communication interface between one or more WTRUs. The Uu interface may be a cellular communication interface. For example, the Uu interface may be a cellular communication interface between a WTRU and an e B. V2X through Uu may be achieved by the WTRU transmitting on the uplink to an e B. V2X through Uu may be achieved by the eNB transmitting on the downlink to the WTRU. For example, V2X through Uu may be achieved by the eNB transmitting on the downlink to the destination WTRU. A V2V operation may be based on communication using the Uu interface, the PC5 interface, and/or a combination of the Uu and PC5 interfaces. [0090] A WTRU may transmit a message to one or more WTRUs in sidelink. For example, a WTRU may transmit a V2X message to one or more WTRUs in sidelink. A receiving WTRU may refer to a WTRU that is receiving a message, for example, receiving a message using one or more transmission/reception parameters determined based on one or more items of context information. A transmitting WTRU may refer to a WTRU that is transmitting a message, for example, transmitting a message using one or more transmission/reception parameters determined based on one or more items of context information. A WTRU may correspond to a road side unit (RSU). An RSU may be a device located on a roadside that provides connectivity support to, or otherwise communicates with, passing vehicles. The receiving WTRU may receive the V2X message in sidelink and/or the receiving WTRU may transmit the V2X message to E-UTRAN in uplink. The E-UTRAN may receive the V2X message from the receiving WTRU (e.g., the RSU) and/or the E-UTRAN may transmit the V2X message to one or more WTRUs at an area (e.g., a local area) in downlink. For example, a WTRU may transmit a V2X message to E-UTRAN in uplink and/or the E-UTRAN may transmit the V2X message to one or more WTRU type RSUs. The WTRU type RSU may transmit the V2X message to WTRUs in sidelink.

[0091] A service (e.g., a service defined for V2X) may support Vehicle-to-Pedestrian (V2P) communication. In the service, a vehicle may communicate with a mobile device and/or a handheld device using one or more of the examples described herein. For example, a vehicle may communicate with a WTRU used by a pedestrian using one or more of the examples described herein.

[0092] The WTRU supporting V2P applications may transmit application layer information. The application layer information may be broadcast. For example, the application layer information may be broadcast by a vehicle with a WTRU supporting V2X Service (e.g., warning to pedestrian), and/or by a pedestrian with a WTRU supporting V2X Service (e.g., warning to vehicle).

[0093] V2P may include the exchange of V2P -related application information between one or more WTRUs. For example, V2P may include the exchange of V2P -related application information between a WTRU for vehicle and a WTRU for a pedestrian. V2P may include the exchange of V2P-related application information between one or more WTRUs (e.g., between one or more WTRUs directly). V2P may include the exchange of V2P -related application information between one or more WTRUs via an infrastructure supporting V2X Service. For example, V2P may include the exchange of V2P-related application information between one or more WTRUs via an RSU, an application server, etc. V2P may include the exchange of V2P- related application information between one or more WTRUs via an infrastructure supporting V2X Service due to the limited communication range of V2P (e.g., limited direct communication range of V2P).

[0094] V2P may be used to warn one or more pedestrians against one or more possible pedestrian collisions. For example, one or more warnings may be provided to a pedestrian to avoid a possible collision with a vehicle. V2P may be used for vulnerable road user safety. For example, a vehicle may detect a pedestrian presence and inform the driver. V2P may be used for pedestrian road safety via V2P awareness messages. For example, a pedestrian may transmit basic awareness messages to vehicles which may perform collision risk assessment and/or inform the driver if a risk of collision may exist.

[0095] A pedestrian WTRU may transmit and/or receive periodic broadcast messages. For example, a pedestrian WTRU may transmit and/or receive periodic broadcast messages depending on the design of the V2P system and/or application layer implementation. One or more V2X messages may be periodic. For example, vehicle and/or pedestrian awareness messages may be periodic. V2X messages may be short (e.g., 50-300 bytes). V2X messages may be transmitted periodically. For example, the V2X messages may be transmitted with a period in the order of hundreds of milliseconds. V2X (e.g., V2P) may be used for collision avoidance, road side user warnings, and/or collision warnings. For example, V2X may be used for collision avoidance, road side user warnings, and/or collision warnings in high-traffic areas (e.g., in urban environments). V2X may be used for collision avoidance, road side user warnings, and/or collision warnings where one or more cars and/or one or more pedestrians may be concentrated in an area (e.g., a small area).

[0096] Messages may be sent using unicast, broadcast, and/or multicast. Messages may be sent using point-to-multipoint services. For example, V2X messages may be sent using unicast, broadcast, and/or multicast. V2X messages may be sent using point-to-multipoint services. V2X messages may be sent using services such as single-cell point-to-multipoint (SC- PTM) and/or Enhanced Multicast Broadcast (eMBMS) capabilities (e.g., of LTE). V2X messages may be sent using unicast, broadcast, and/or multicast for the examples involving a Uu interface. Multicast transmission built into D2D may be used. For example, multicast transmission built into D2D may be used for the examples and/or examples involving a PC5 interface. V2X-enabled WTRUs may spend time (e.g., a considerable amount of time) performing transmission and/or reception of broadcast messages. For example, due to the broadcast nature of the messaging, V2X-enabled WTRUs may spend time (e.g., a considerable amount of time) performing transmission and/or reception of such messages given the number (e.g., large number) of vehicles and/or pedestrians in an area.

[0097] WTRUs may not have any specific power limitations. For example, vehicle WTRUs may not have any specific power limitations as they may be powered by the vehicle's energy system. A pedestrian WTRU, such as a V2X enabled pedestrian WTRU, for example, may be powered by the handset's battery. A pedestrian WTRU in a high-traffic area may receive and/or process messages. The pedestrian WTRU in a high-traffic area may receive and/or process messages frequently. Power consumption (e.g., power consumption relating to a pedestrian WTRU) may be a concern and/or may be attempted to be minimized. For example, power consumption associated with reception of V2X messages may be a concern and/or may be minimized. A number (e.g., a large number) of messages may be irrelevant for a specific pedestrian. For example, messages transmitted by vehicles which may be in danger with collision with a pedestrian may be relevant. Given that warning messages may be transmitted by many vehicles, a number (e.g., a large number) of messages may be irrelevant for a specific pedestrian. Requiring a pedestrian WTRU to receive and/or process one or more messages (e.g., all messages) at the access stratum layer before the application layer determines if a specific message is relevant may result in a larger than needed power consumption and/or overhead for the pedestrian WTRU handset.

[0098] A pedestrian WTRU may transmit warning and/or awareness messages to vehicles. For example, a pedestrian WTRU may periodically transmit warning and/or awareness messages to surrounding vehicles. Having such transmissions occur on a regular basis may result in a larger than needed power consumption. It may be desirable to reduce the transmission overhead of the pedestrian WTRU while maintaining the requirements for the V2P service.

[0099] The term "WTRU," as used herein, may represent a single V2X-enabled device, which may be an actual mobile device, a vehicle which has V2X communication capability, and/or a roadside unit meant to improve performance of the V2X system. The term "pedestrian WTRU," as used herein, may represent a handheld mobile device that may be enabled for V2P services. The term "e B," as used herein, may represent an e B employed in LTE

infrastructure communication, and/or which can provide communication services for in-coverage D2D communications. The eNB may be deployed on a cellular tower, and/or the eNB may be deployed as a road-side unit. If the eNB is deployed as a road-side unit, the eNB may have D2D communication functionality and/or conventional eNB functionality.

[0100] The term SC-PTM may refer to a broadcast/multicast service, such as the SC- PTM designed for LTE operations and/or a point-to-multipoint service, including eMBMS, etc. Examples may be described in the context of V2P communication (e.g., from a vehicle to a pedestrian WTRU). Examples may apply to P2V communications (e.g., from a pedestrian WTRU to a vehicle), and vice-versa.

[0101] Dynamic and/or contextual configuration of V2X radio communication parameters may be utilized, for example, to attempt to improve power efficiency of V2P/P2V communications. Examples of dynamic and/or contextual configuration of V2X radio communication parameters may include the use of location, heading, and other dynamically determined information in order to determine or set one or more V2X communication parameters or settings. Such techniques may improve the power efficiency of V2P/P2V communications for one or more devices (e.g., a V2X WTRU, such as V2P devices, an RSU, and/or an eNB).

[0102] A WTRU may be configured to determine radio configuration parameters of the WTRU based on associated contextual information. The WTRU may be a V2X WTRU. For example, the V2X WTRU may be configured to determine V2X radio configuration parameters of the V2X WTRU based on associated contextual information. The radio configuration parameters may include a radio interface/mechanism. A radio interface and/or mechanism may include a communication via one or more of the PC5 interface, Uu interface, and/or other radio interface. The radio configuration parameters may include power control parameters. The radio configuration parameters may include transmission/reception configuration parameters.

[0103] Transmission/reception configuration parameters may include resource pool(s). Transmission/reception configuration parameters may include the modulation and coding scheme (MCS), the number of resource blocks (RBs) for a transport block (TB) supported, etc. Transmission/reception configuration parameters may include frequency hopping configuration. Transmission/reception configuration parameters may include a set of time resource patterns of transmission (T-RPTs) supported. Transmission/reception configuration parameters may include L2 group identities. Transmission/reception configuration parameters may include a set of radio network temporary identifiers (RNTIs) to monitor. For example, transmission/reception configuration parameters may include a set of radio network temporary identifiers (RNTIs) to monitor for PC5 interface scheduling, SC-PTM, DCI monitoring, etc. Transmission/reception configuration parameters may include eMBMS parameters (e.g. temporary mobile group identity (TMGI)) to monitor, etc. Transmission/reception configuration parameters may include a priority of processed message. Transmission/reception configuration parameters may include a threshold battery level. The radio configuration parameters may include a parameter

configuration. For example, the V2X radio configuration parameters may include a V2X parameter configuration. The parameter configuration may include an activation/deactivation status. The parameter configuration may include a DRX configuration. The parameter configuration may include a DTX configuration. The parameter configuration may include transmission rate parameters. The parameter configuration may include RX/TX Identities. The parameter configuration may include a message reception/processing rate and/or periodicity. The parameter configuration may include a message transmission rate and/or periodicity.

[0104] The WTRU (e.g. the WTRU supporting V2X) may be configured with one or more sets of V2X radio configuration parameters. For example, a V2X WTRU may be configured with one or more sets of V2X radio configuration parameters. The WTRU may be configured with one or more sets of radio configuration parameters which may be associated with contextual information. Different sets of radio configuration parameters may be associated with different contextual information. For example, a WTRU may select which radio configuration to use based on the current context information (e.g., current location, heading, etc.) of the WTRU. The associated contextual information may be information related to one or more WTRUs (e.g., a V2X WTRU or another WTRU). Contextual information regarding a WTRU may include one or more dynamic parameters related to a current status or state of the WTRU. For example, the contextual information of a WTRU (e.g., a V2X WTRU or another WTRU) may include location information (e.g., absolute location information and/or relative location information) of the WTRU. The contextual information of a WTRU may include movement information of the WTRU. The contextual information of a WTRU may include status information of the WTRU. [0105] Upon determining one or more items of contextual information, the WTRU may select one or more transmission and/or reception parameters based on the one or more items of context information. For example, a certain location (e.g., in latitude/longitude) may be associated with a certain RNTI that the WTRU may use for transmission and/or reception. In an example, a D2D resource pool may be associated with a certain heading of the WTRU. The selection of a given transmission/reception parameter may be based on a single item of context information or multiple items of context information. An item of context information may be used to select a single transmission/reception parameter and/or multiple transmission/reception parameters. One or more transmission/reception parameters may be selected based on the combination of multiple items of context information.

[0106] For example, the contextual information associated with a set of configuration parameters may include geographical location of the WTRU and/or the contextual information associated with a set of configuration parameters may include geographical location of another WTRU. For example, the contextual information associated with a set of configuration parameters may include longitude, latitude, and/or elevation; in a range of the longitude, latitude, and/or elevation; and/or with respect to a known reference point of the WTRU itself and/or of another WTRU. The contextual information associated with a set of configuration parameters may include speed, direction of heading, and/or acceleration of the WTRU itself and/or of another WTRU. The contextual information associated with a set of configuration parameters may include status of the WTRU itself, of the pedestrian using the WTRU, and/or of another WTRU (e.g., vehicle and/or other). The contextual information associated with a set of configuration parameters may include proximity to street indication of the WTRU itself and/or of another WTRU (e.g., vehicle and/or other).

[0107] The contextual information associated with a set of configuration parameters may include an in-building indication. The contextual information associated with a set of configuration parameters may include an in-car indication. The contextual information associated with a set of configuration parameters may include an indication of proximity to a specific area and/or landmark. For example, the contextual information associated with a set of configuration parameters may include an in parking lot indication. The contextual information associated with a set of configuration parameters may include an on motorcycle/bicycle or other non-car street vehicular indication. The contextual information associated with a set of configuration parameters may include a level of risk/danger based on any or a combination of the information provided herein. The contextual information associated with a set of configuration parameters may include a WTRU battery power (e.g., compared to a configured threshold). The contextual information associated with a set of configuration parameters may include a user interaction.

[0108] The contextual information may be determined by the WTRU based on geolocation information. For example, the contextual information may be determined by the WTRU based on a global positioning system (GPS), global navigation satellite system (GNSS), observed time difference of arrival (OTDOA), sensor information, and/or radar. The contextual information may be determined by the WTRU based on navigation information. The contextual information may be determined by the WTRU based on readings of speed, acceleration, and/or heading. The contextual information may be determined by the WTRU based on radio signal measurements. The contextual information may be determined by the WTRU based on a connection to other RATs. For example, the contextual information may be determined by the WTRU based on a connection to a car system and/or another WTRU via Bluetooth. The contextual information may be determined by the WTRU based on reception of any of the information provided herein related to another WTRU and/or obtained from a WTRU and/or e B via a PC5 interface or Uu interface. The contextual information may be determined by the WTRU based on a determination of the information provided herein, and/or processed combination of any of the information provided herein from an application layer residing within the WTRU and/or elsewhere in the network.

[0109] The vehicular and/or pedestrian WTRU may receive a configuration for one or more parameters from an application server located on the network. For example, the vehicular and/or pedestrian WTRU may receive a configuration for one or more parameters from a V2X application server located on the network. The vehicular and/or pedestrian WTRU may receive a configuration for one or more parameters from a network signaling (such as radio resource control (RRC)/ non-access stratum (NAS)). The vehicular and/or pedestrian WTRU may receive a configuration for one or more parameters from a RSU node. For example, the vehicular and/or pedestrian WTRU may receive a configuration for one or more parameters from a RSU node using an application layer protocol and/or over the control plane using RRC/NAS-like protocol. The vehicular and/or pedestrian WTRU may receive a configuration for one or more parameters from another device, such as another V2X device. For example, the vehicular and/or pedestrian WTRU may receive a configuration for one or more parameters from another device via direct PC5 interface communication using a control plane protocol over PC5 interface. The vehicular and/or pedestrian WTRU may receive a configuration for one or more parameters from another radio access technology (e.g., Bluetooth, WI-FI, etc.) The vehicular and/or pedestrian WTRU may receive a configuration for one or more parameters from the WTRU. For example, the vehicular or pedestrian WTRU may receive a configuration for one or more parameters that are statically configured within the WTRU (e.g. the USEVI).

[0110] The WTRU may be configured to determine the set of radio configuration parameters to be used from the configuration and/or the associated contextual information. For example, the WTRU may be configured to determine, based on the context, the set of V2X radio configuration parameters to be used from the configuration and/or the associated contextual information.

[0111] The WTRU may be configured to report contextual information (e.g.,

measurement) of the WTRU to the network, RSU, and/or application server (e.g., V2X application server). The WTRU may be configured to receive a set of radio configuration parameters. For example, the WTRU may be configured to receive a set of V2X radio configuration parameters. The WTRU may be configured to report the set of contextual information periodically and/or when the WTRU detects changes in the context.

[0112] A WTRU may be configured to receive and/or process broadcast transmissions. Broadcast transmissions may include one or more transmissions which may be received by one or more WTRUs. Broadcast transmissions may include direct WTRU-to-WTRU transmissions (e.g. over PC5), and/or broadcast transmissions may include transmissions by a WTRU and/or by an e B over the Uu interface using a broadcast mechanism, such as MBMS, SC-PTM, etc. In an example, broadcast transmissions may not exclude WTRU-to-WTRU transmissions in 5G and/or broadcast mechanisms adopted for 5G. For example, a WTRU may be configured to receive and/or process broadcast transmissions that may be sent by transmitters located in an area and/or location of interest that may be relevant to the receiving WTRU. The transmitting WTRU may broadcast with a broadcast parameter. A broadcast parameter may be associated with contextual information of a WTRU (e.g., a transmitting WTRU and/or receiving WTRU). The contextual information of the WTRU may include location, movement, status, etc., information of the WTRU. For example, the transmitting WTRU may broadcast with a broadcast parameter that may be associated with a location (e.g., a current location) of the transmitting WTRU and/or associated with the contextual information of the intended receivers. The receiving WTRU may listen to the broadcasts associated with the broadcast parameters that may be associated with the receiving WTRUs contextual information. For example, the receiving WTRU may listen to the broadcasts associated with the broadcast parameters that may be associated with the receiving WTRUs location, movement, status, etc. The receiving WTRU may listen to messages using the broadcast parameters that may be associated with the receiving WTRUs contextual information (e.g., location) while the receiving WTRU may be in the reception range of one or more broadcast transmitters. The receiving WTRU may listen to broadcasts associated with multiple locations relevant to the receiving WTRU. For example, the receiving WTRU may listen to broadcasts associated with neighboring locations of the receiving WTRU. The transmitting WTRU may transmit using one or more broadcast parameters. The transmitting WTRU may determine the broadcast parameters to transmit with, based on a configured mapping that may be associated with the location of the WTRU. The receiving WTRU may determine the broadcast parameters to receive with, based on a configured mapping that may be associated with the location of the WTRU.

[0113] A vehicle WTRU equipped with V2P capability may broadcast (e.g., periodically broadcast) one or more V2X messages. The V2X messages may include warning messages. For example, a vehicle WTRU equipped with V2P capability may broadcast (e.g., periodically broadcast) warning messages destined to pedestrian WTRUs using the Uu interface. The eNB may perform the broadcast transmission using SC-PTM. For example, the eNB may perform the broadcast transmission using SC-PTM with broadcast parameters associated with the vehicle WTRU's location. The broadcast parameters may include configuration parameters. For example, the broadcast parameters may include a group RNTI. A location of a vehicle WTRU may be associated with a specific group RNTI to use to receive and/or transmit the broadcasts. The broadcast parameters may include transmit power. For example, the broadcast parameters may include transmit power, where each potential location of a vehicle WTRU may be associated with a specific transmit power required to reach that location. The broadcast parameters may include resource pool/transmission parameters. Resource pool/transmission parameters may include resources for transmission and/or repetition parameters. For repetition parameters, a location may have the message repeated a number of times and/or with a periodicity.

[0114] FIG. 3 shows an example vehicle WTRU 308. The vehicle WTRU 308 may be equipped with V2X capability to provide one or more of a collision warning, control loss warning, and/or emergency stop. For example, the vehicle WTRU 308 may be equipped with V2X capability so that the vehicle WTRU 308, and/or the pedestrian WTRU 310A and/or pedestrian 310B (hereafter collectively referred to as pedestrian WTRU 310), may be warned of a potential collision. V2X may be used to warn one or more vehicle WTRUs 308 against one or more vehicle collisions. V2X may be used to warn one or more pedestrian WTRUs 310 against one or more pedestrian collisions. V2X may be used for vulnerable road user safety. For example, the vehicle WTRU 308 may detect a pedestrian presence and inform the driver of the detected pedestrian. V2X may be used for pedestrian road safety via awareness messages. For example, a pedestrian WTRU 310 may transmit basic awareness messages to vehicle WTRUs 308 which may perform collision risk assessment and/or inform the driver if a risk of collision may exist.

[0115] The vehicle WTRU 308 may transmit a broadcast. For example, the vehicle WTRU 308 may periodically transmit a broadcast. The broadcast transmission may include one or more broadcast messages. For example, the vehicle WTRU 308 may broadcast one or more broadcast messages destined for pedestrian WTRU 310. The vehicle WTRU 308 may broadcast one or more broadcast messages destined for a pedestrian WTRU 310 using the Uu interface. The eNB 312 may broadcast one or more broadcast messages using SC-PTM. The broadcast parameters used for transmission/reception may be associated with the vehicle WTRU 308 and/or the broadcast parameters may be associated with the pedestrian WTRU 310. The broadcast parameters associated with the transmission/reception may include contextual information (location, movement, status, etc.) information associated with the vehicle WTRU 308 and/or the pedestrian WTRU 310. The broadcast parameters may include configuration parameters. The broadcast parameters may include a group RNTI that may be associated with the contextual information of the vehicle WTRU 308 and/or the pedestrian WTRU 310. For example, the broadcast parameters may include a group RNTI 1 302, a group RNTI 2 304, and/or a group RNTI 3 306. [0116] One or more pedestrian WTRUs 310 may listen to (e.g., decode) one or more broadcast messages transmitted by the vehicle WTRU 308. One or more pedestrian WTRUs 310 may listen to (e.g., decode) one or more broadcast messages transmitted by the vehicle WTRU 308 using reception parameters that may be based on the contextual information (e.g., location, movement, status, etc.) of the one or more pedestrian WTRUs 310. For example, the pedestrian WTRU 310A may listen to the group RNTI 1 302 and the group RNTI 2 304 messages, based on the pedestrian WTRU 310A being located within a predefined distance of the group RNTI 1 302 and/or the group RNTI 2 304. The pedestrian WTRU 310A may listen to the group RNTI 1 302 and the group RNTI 2 304 messages, based on the pedestrian WTRU 310A having a direction of heading related to group RNTI 1 302 and/or group RNTI 2 304. The pedestrian WTRU 310A may decode messages transmitted by vehicle WTRU 308 that are group RNTI 1 302 and group RNTI 2 304 messages, based on the pedestrian WTRU 310A being located within a predefined distance of group RNTI 1 302 and group RNTI 2 304 and/or pedestrian WTRU 310A having a direction of heading related to group RNTI 1 302 and group RNTI 2 304. Also, or alternatively, the pedestrian WTRU 310B may listen to group RNTI 3 306 messages, based on the pedestrian WTRU 310B being located within a predefined distance of group RNTI 3 306 and/or pedestrian WTRU 310B having a direction of heading related to group RNTI 3 306, etc.

[0117] The eNB responsible for broadcasting a specific message using SC-PTM may be configured with a set of broadcast parameters to employ. For example, the eNB responsible for broadcasting a specific message using SC-PTM may be configured with a set of broadcast parameters to employ based on the location of the vehicle WTRU and/or the pedestrian WTRU. The configuration may include a set of parameter associated with a number of geographically non-overlapping areas in the cell. The configuration may be provided to the eNB from one or more sources. For example, the configuration may be provided to the eNB from a V2P application server residing on the network and/or controlling the V2P system. The configuration may be provided to the eNB from an operator OAM and/or similar application. The

configuration may be provided to the eNB from the WTRU being statically configured in the eNB by the operator via OAM. A transmitting WTRU may provide a configuration initially, periodically, and/or at the time of transmitting WTRU message transmission.

[0118] Vehicle behavior may be provided by the vehicle WTRU. For example, the vehicle WTRU may transmit a warning message to the eNB to allow the eNB to broadcast the message to pedestrian WTRUs (e.g., pedestrian WTRUs in the vicinity). The vehicle WTRU may transmit a warning message to the eNB to allow the eNB to broadcast the message to pedestrian WTRUs (e.g., pedestrian WTRUs in the vicinity) periodically, or at a time instant which may be triggered by a driving event in the vehicle. For example, the vehicle WTRU may transmit a warning message to the eNB to allow the eNB to broadcast the message to pedestrian WTRUs in the vicinity if the vehicle is achieving a location, speed, and/or acceleration. The vehicle WTRU may provide the location of the vehicle WTRU to the eNB. For example, the vehicle WTRU may provide the location of the vehicle WTRU to the eNB regularly. The location may be provided using uplink control messages. For example, the location may be provided using uplink control messages sent via RRC, and/or the location may be embedded within the warning message to be broadcast.

[0119] The eNB may use the configuration to determine broadcast parameters. For example, the eNB, upon reception of the warning message, may use the configuration to determine the broadcast parameters (e.g., required broadcast parameters) enumerated herein. For example, the eNB may use the configuration to determine the broadcast parameters (e.g., the group RNTI) to use for broadcasting the message using SC-PTM.

[0120] A pedestrian WTRU may be a receiving WTRU. For example, a pedestrian WTRU may be a receiving WTRU that may receive a broadcast using one or more parameters determined based on context information. The receiving WTRU may determine the broadcast parameters using the configuration of the receiving WTRU and/or the location of the receiving WTRU. For example, the receiving WTRU may determine the group RNTI the receiving WTRU may listen to using the configuration of the receiving WTRU and/or the location of the receiving WTRU. The receiving WTRU may determine the location (e.g., via GPS, OTDOA, or other mechanisms) of the receiving WTRU and/or the receiving WTRU may determine the associated group RNTI to use to listen to broadcasts based on the configuration of the receiving WTRU. The receiving WTRU may receive the location of the receiving WTRU from the eNB and/or from another WTRU. The receiving WTRU's configuration (e.g., the RNTI to use for a specific location) may be provided in one or more ways. For example, the receiving WTRU's configuration may be provided from the V2P application running on the receiving WTRU. The receiving WTRU's configuration may be provided from a V2P application server residing on the network and/or controlling the V2P system. The receiving WTRU's configuration may be provided from the e B. The receiving WTRU's configuration may be provided by being statically configured in the receiving WTRU.

[0121] The receiving WTRU may determine a broadcast parameter and/or set of broadcast parameters, based on the configuration. For example, the receiving WTRU may determine one or more group RNTIs to listen to, based on the configuration. The receiving WTRU may listen to broadcasts using the broadcast parameters. Periodically, and/or as a result of an event (e.g., the pedestrian location changes and/or the receiving WTRU receives a new configuration), the receiving WTRU may re-determine the broadcast parameters to use for reception and/or the receiving WTRU may listen (e.g., start to listen) to broadcasts. The receiving WTRU may re-determine the broadcast parameters to use for reception and/or the receiving WTRU may listen (e.g., start to listen) to broadcasts based on the new broadcast parameters.

[0122] A pedestrian WTRU (e.g., a receiving WTRU) may receive messages from vehicle WTRUs. For example, a pedestrian WTRU may receive messages from vehicle WTRUs when the vehicle WTRUs are in the vicinity of the pedestrian WTRU. Messages from vehicles which may be outside of the pedestrian's area (e.g., which may not pose a collision risk) may not be received and/or processed by the pedestrian WTRU. As shown in FIG. 2, a 1 km cell area may be subdivided into two or more (e.g., forty -four) locations with a radius of 150 meters. The 150 meters may correspond to the V2P communication range. By configuring the broadcast reception parameters of the pedestrian WTRU, the pedestrian WTRU may listen for broadcast messages which may come from vehicle WTRUs located in the same location and/or a neighboring location as the pedestrian WTRU is located. The pedestrian WTRU may ignore and/or may not receive messages from vehicles located outside the same location as the pedestrian WTRU and/or a neighboring location of the WTRU.

[0123] The configuration may map a group RNTI to a distance. For example, the configuration may map a group RNTI to the distance from a street, boulevard, and/or highway. The application layer, network, etc. may provide the pedestrian WTRU with streets (e.g., a list of streets) that may cause the pedestrian WTRU to receive V2P messages. For example, the application layer, network, etc. may provide the pedestrian WTRU with a list of streets that may cause the pedestrian WTRU to receive V2P messages based on the WTRU's current position. The list of streets may be provided to the WTRUs navigation system as a list of paired coordinates, identifiers, etc. For example, the list of streets may be provided to the WTRUs navigation system as a list of paired coordinates, identifiers, etc., so that the navigation system may identify the list of streets within the map of the navigation system. The pedestrian WTRU may monitor messages using the group RNTI. For example, the pedestrian WTRU may monitor messages using the group RNTI when the pedestrian WTRU is determined to be within a distance from a particular street. The application layer may send triggers of when to start and/or stop monitoring the RNTI along with the RNTI value to the lower layers as the WTRUs position changes. The upper layers may send an identifier (e.g., an identifier other than the RNTI) to the lower layers. The lower layers may convert the identifier into the group identifier with specific rules (e.g., rules determined by the configuration).

[0124] The transmitting WTRU may transmit messages to the eNB. The messages may contain location information, direction, speed, acceleration, etc. The transmitting WTRU may determine the street (e.g., the identifier and/or coordinate pair). For example, the transmitting WTRU may determine the street (e.g., the identifier and/or coordinate pair) a-priori. The street may be determined at the eNB and/or at the network. For example, the street may be determined at the eNB and/or at the network based on the information provided by the eNB. The eNB and/or the network may determine the group RNTI to be used for transmission through broadcast. For example, the eNB and/or the network may determine the group RNTI to be used for transmission through broadcast based on a similar mapping to be done in the receiving pedestrian WTRU. The pedestrian WTRU may receive messages from vehicles travelling on streets/boulevards/highways which the pedestrian WTRU may be close to and/or may be moving toward.

[0125] The network may be configured to encode a set of group RNTI and/or associated location(s). For example, the network may be configured to efficiently encode a set of group RNTI and/or associated location(s). The network may associate a group RNTI values to points on a geo-graphical grid. The network may indicate information. For example, the network may indicate a position (e.g., the exact position) of one of the point(s). For example, the network may indicate the exact position of reference points. The network may indicate the distance between two or more points. The network may indicate the number of points in a dimension. For example, the network may indicate the number of points in a longitude, latitude, and/or elevation. The network may indicate the group RNTI associated with a point on the grid. For example, the network may indicate the group RNTIs associated with the reference point on the grid. The network may indicate the group RNTI offset. For example, the network may indicate an offset in the count for the group RNTI.

[0126] The WTRU may determine the associated group RNTI to one or more of the geographical points. The WTRU may determine the associated group RNTI to one or more of the geographical points based on pre-defined rules. Determining the associated group RNTI to one or more of the geographical points based on pre-defined rules may be advantageous as it may reduce the amount of signaling required to indicate the associated group RNTI to each geographic center point.

[0127] Multicast traffic channel (MTCH) may be associated with a location. An eNB may utilize eMBMS for broadcast of vehicle warning messages. For example, an eNB may utilize eMBMS for broadcast of vehicle warning messages received from vehicle WTRUs. The configurations used by the receiving WTRU may indicate the MTCH to listen to. For example, the configurations used by the receiving WTRU may indicate the MTCH to listen to, based on a location. The MBMS components in the network (e.g., MBMS server and/or broadcast multicast service center (BM-SC)) may be responsible for configuring the eNBs (e.g., appropriate eNBs) to broadcast the message received from the vehicle WTRUs. The procedures at the transmitting WTRU, eNB, and/or receiving WTRU may be identical or similar to the examples described herein. The vehicle WTRU and/or pedestrian WTRU behavior may be similar to those described herein.

[0128] A vehicle WTRU equipped with V2P capability may broadcast (e.g., periodically broadcast) warning messages destined to pedestrian WTRUs using the PC5 interface. The vehicle WTRU may transmit on a resource pool. The resource pool may depend on the location of the vehicle WTRU. The transmitting WTRU may select the pool to use for transmission. For example, the transmitting WTRU may select the pool to use for transmission based on a configuration which may associate the pool to be used with the location of the WTRU. The transmitting WTRU may receive the configuration in one or more ways. For example, the transmitting WTRU may receive the configuration from the V2P application on the vehicle WTRU. The transmitting WTRU may receive the configuration from a V2P application server residing in the network. The transmitting WTRU may receive the configuration from the eNB as part of the PC5 interface resource configuration and/or other D2D configuration (e.g., through dedicated signaling and/or via SIBs specific to a PC5 interface configuration). The transmitting WTRU may receive the configuration from the WTRU statically configuring the configuration in the WTRU.

[0129] The configuration file may dictate parameters associated with PC5 interface transmission. For example, the configuration file may dictate T-RPT, transmit power, scheduling period, etc. The configuration file may dictate parameters associated with PC5 interface transmission, based on location.

[0130] FIG. 4 illustrates an example vehicle WTRU 408. The vehicle WTRU 408 may be equipped with V2X capability to provide one or more of a collision warning, control loss warning, and/or emergency stop. For example, the vehicle WTRU 408 may be equipped with V2X capability so that the vehicle WTRU 408 and/or the pedestrian WTRU 406 may be warned of a potential collision. V2X may be used to warn one or more vehicle WTRUs 408 against one or more vehicle collisions. V2X may be used to warn one or more pedestrian WTRUs 406 against one or more pedestrian collisions. V2X may be used for vulnerable road user safety. For example, the vehicle WTRU 408 may detect a pedestrian presence and inform the driver of the detected pedestrian. V2X may be used for pedestrian road safety via awareness messages. For example, a pedestrian WTRU 406 may transmit basic awareness messages to vehicle WTRUs 408 which may perform collision risk assessment and/or inform the driver if a risk of collision may exist.

[0131] The vehicle WTRU 408 may transmit a broadcast (e.g., periodically transmit a broadcast). The broadcast transmission may include one or more messages. For example, the vehicle WTRU 408 may broadcast one or more messages destined for pedestrian WTRU 406. The vehicle WTRU 408 may broadcast one or more messages destined for a pedestrian WTRU 406 using the PC5 interface. The vehicle WTRU 408 may broadcast one or more messages based on contextual information. The parameters for broadcast reception/transmission may include configuration parameters. The parameters may include one or more resource pools. For example, the vehicle WTRU 408 may broadcast using a first resource pool 402 and/or the vehicle WTRU 408 may broadcast one or more messages using a second resource pool 404, based on location information of the vehicle WTRU 408 and/or the pedestrian WTRU 406. As shown in FIG. 4, the first resource pool 402 may be associated with a first intersection 401 and/or the second resource pool 404 may be associated with a second intersection 403. [0132] As described herein, the vehicle WTRU 408 may broadcast one or more messages using one or more resource pools based on contextual information of the vehicle WTRU 408 and/or the pedestrian WTRU 406. For example, the vehicle WTRU 408 may transmit one or more messages to the pedestrian WTRU 406 if the vehicle WTRU 408 and the pedestrian WTRU 406 are within a same resource pool. The vehicle WTRU 408 may transmit one or more messages to the pedestrian WTRU 406 if the vehicle WTRU 408 and the pedestrian WTRU 406 are within resource pools that may be positioned within a predefined distance of one another. The vehicle WTRU 408 may transmit one or more messages to the pedestrian WTRU 406 if the vehicle WTRU 408 and/or the pedestrian WTRU 406 have a direction of heading that may result in the vehicle WTRU 408 and/or the pedestrian WTRU 406 being within a same resource pool and/or within a predefined distance of resource pools. For example, vehicle WTRU 408 may transmit one or more messages to the pedestrian WTRU 406 if the vehicle WTRU 408 and/or the pedestrian WTRU 406 have a speed, direction of heading, and/or acceleration that may result in an unsafe condition (e.g., a collision of the vehicle WTRU 408 and the pedestrian WTRU 406).

[0133] A configuration may be used by the pedestrian WTRU. A configuration used by the pedestrian WTRU may be obtained in the same or similar ways as described herein. The pedestrian WTRU may obtain (e.g., first obtain) its configuration upon startup. For example, the pedestrian WTRU may obtain (e.g., first obtain) its configuration upon startup when the V2P application is launched, when determined by the V2P application or network, and/or

periodically. The pedestrian WTRU may update (e.g., regularly update) its configuration. For example, the pedestrian WTRU may update (e.g., regularly update) its configuration when the location of the pedestrian WTRU changes, and/or when the pedestrian WTRU is instructed to perform a configuration change. For example, the pedestrian WTRU may update (e.g., regularly update) its configuration when the pedestrian WTRU is instructed to perform a configuration change from the network and/or V2P application server. The pedestrian WTRU may be configured to listen to the PC5 interface resource pool(s) associated with the location of the pedestrian WTRU, as dictated by the pedestrian WTRU's configuration. For example, the pedestrian WTRU may be configured to listen to the PC5 interface resource pool(s) associated with the location of the pedestrian WTRU, as dictated by its configuration, periodically, and/or at the occurrence of a predefined event. The pedestrian WTRU may determine which pool the pedestrian WTRU may monitor. For example, the pedestrian WTRU may determine which pool the pedestrian WTRU may monitor based on a location of the pedestrian WTRU and/or the mapping of the location to resource pool(s) determined by the configuration (e.g., as the pedestrian WTRU changes its location and/or regularly).

[0134] A resource (e.g., pool, group RNTI, and/or other) may be associated with a vehicle position, direction, speed, etc. A WTRU configured to receive broadcast transmissions may receive and/or process the broadcast transmissions being sent by transmitters with specific physical characteristics which may be relevant to the receiving WTRU. For example, a WTRU configured to receive broadcast transmissions may receive and/or process the broadcast transmissions being sent by transmitters with characteristics associated with the entity to which the transmitting device is attached. The physical characteristics may be static. For example, for machine communications, the physical characteristics may be the class of machine and/or device that is communicating. The physical characteristic may change dynamically (e.g., may change with time). For example, in V2X, the characteristics may refer to the vehicle speed, location, heading, etc.

[0135] The WTRU may be configured by layers (e.g., higher layers) with a set of resources and/or special characteristics. The set of resources may include a resource pool, T- RPT, and/or other physical layer characteristics. Special characteristics may include an identity, group RNTI, etc. The set of resources and/or special characteristics may be referred to as the "set of resources/identifiers." The set of resource/identifiers may be associated with a set of V2X related information. For example, the set of resource/identifiers may be associated with a vehicle position, speed, and/or direction. The WTRU may be configured to determine the set (e.g., relevant set) of resources/identifiers. For example, the WTRU may be configured to determine the set (e.g., relevant set) of resources/identifiers based on the position/direction/speed of the WTRU. The WTRU may receive and/or process the data from the set of relevant resource s/i dentifi er s .

[0136] The WTRU may be configured to determine (e.g., determine based on one or more of its geographical location, direction, and/or speed) the set of relevant resources/identifiers to monitor. For example, the WTRU may be configured to determine the set of relevant resources/identifiers to monitor, based on one or more of a geographical location, direction, and/or speed of the WTRU. The WTRU may determine the set of relevant resources/identifiers based on the risk of collision. For example, the vehicle may get within a specific pre-defined distance of the pedestrian WTRU in the pre-defined interval (e.g., the next pre-defined interval) of time. The risk of collision may be based on an interpolation of the trajectories. For example, the risk of collision may be based on whether the WTRU trajectory may intersect the trajectory of the vehicle and/or whether the WTRU trajectory and the vehicle trajectory may get within a predefined distance. A WTRU may be configured to listen to broadcasts for vehicles travelling in the east/west direction when the WTRU is heading north/south.

[0137] The vehicle WTRU may be configured with a set of resources/identifiers associated with V2X related information. V2X related information may include position, speed, and/or direction. The vehicle may determine the relevant set of resources/identifiers to use when transmitting V2X data. For example, the vehicle may determine the relevant set of

resources/identifiers to use when transmitting V2X data, based on the configuration.

[0138] A road side unit (RSU) may determine a set of resources/identities. The vehicle WTRU and/or pedestrian WTRU may receive the configuration of resources/identifiers and/or associated location, speed, and/or direction from a controller and/or a RSU. The WTRU may be configured to monitor the RSU and/or controller for periodic message and/or indications of changes in the configuration. The RSU may be configured to determine how to allocate and/or associate the set of resources/identities. For example, the RSU may be configured to determine how to allocate and/or associate the set of resources/identities dynamically. The RSU may be configured to determine how to allocate and/or associate the set of resources/identities based on information the RSU receives from one or more WTRUs. The RSU may configure the WTRUs upon changes. For example, the RSU may receive broadcast transmissions (e.g., periodic broadcast transmissions) from one or more vehicle WTRUs. The RSU may determine (e.g., dynamically determine) a configuration to be used by a pedestrian WTRU. For example, the RSU may determine (e.g., dynamically determine) a configuration to be used by a pedestrian WTRU, based on a determination of which vehicle WTRU broadcasts may be relevant to a pedestrian WTRU. The configuration may be sent to the pedestrian WTRU. The pedestrian WTRU may use the configuration to determine which resources/identities to monitor.

[0139] The configuration from the RSU may be sent to the pedestrian WTRU and/or may be received by the pedestrian WTRU in one or more ways. For example, the pedestrian WTRU may receive the configuration as part of an initial communication and/or connection procedure with the RSU. The pedestrian WTRU may expect the configuration to be sent using resources/identifiers which the RSU may use. Resources/identifiers may include a specific resource pool, a specific RNTI, etc. The pedestrian WTRU may receive the configuration from the RSU at predefined times. The pedestrian WTRU may receive the configuration from the RSU infrequently. For example, by receiving the configuration from the RSU infrequently, the pedestrian WTRU may be capable of listening for a configuration from the RSU. The pedestrian WTRU may request the configuration. For example, the pedestrian WTRU may request the configuration by communicating with the RSU when triggered by a timer, by the application layer, by a change in pedestrian WTRU location, etc. The pedestrian WTRU may communicate with the RU using sideline and/or Uu interfaces. The request by the pedestrian WTRU to the RSU may contain one or more of the pedestrian WTRU' s location, indoor/outdoor status, speed, direction, user behavior (listening to music, on a call, etc.), etc.

[0140] The WTRU may prioritize messages. The WTRU may be configured with a set of resources/identities associated with a set of messages. The WTRU may be configured with a set of resources/identities associated with a set of message priorities. The pedestrian WTRU may be configured to monitor a subset of messages (e.g., warning messages). The pedestrian WTRU may be configured to monitor the subset of messages based on a priority. For example, the pedestrian WTRU may be configured to monitor the subset of messages based on a priority in order to preserve battery. The subset of messages (e.g., warning messages) may be associated with a resource/identity and/or subset of resource/identities. For example, the subset of messages may be associated with an RNTI, PC5 interface resource pool, etc. The WTRU may receive messages associated with the subset of messages it chooses to receive. The WTRU may receive messages associated with the subset of messages it chooses to receive at a specific time. For example, in conditions of low battery power, the WTRU may receive and/or process warning messages. A low battery power condition may include the WTRU determining that the WTRU has an amount of power lower than a configured threshold. In conditions of low battery power, the WTRU may ignore messages related to non-critical information exchange with vehicles. For example, in conditions of low battery power, the WTRU may ignore messages related to multimedia and/or media sharing. The messages to be processed by a WTRU (e.g., messages to be processed by a WTRU at a given time) may be configured by the application layer. For example, a user may interact with an application on a smartphone and may select the priority of messages that the smartphone may process at a given time. Such action by the user may be translated to have the WTRU monitor a message (e.g., an associated message) or message priorities. The action may be translated by the application interaction with the low layers of the WTRU.

[0141] A WTRU may determine when it may be relevant to monitor for messages. For example, a WTRU may determine when it may be relevant to monitor for V2P messages. The WTRU may be configured to determine when to start monitoring for messages, such as V2P messages. For example, the WTRU may determine when to activate/deactivate V2X monitoring. The WTRU may be configured to determine when it may be in an environment where it may be irrelevant to monitor for V2P messages. Such environments may include inside a building, in a pedestrian-only street, in a park, etc. The WTRU access stratum may be indicated by higher layers when it may be relevant and/or when it may be irrelevant to monitor for V2P messages. The access stratum may determine to activate and/or deactivate V2P monitoring. For example, a navigation system application may determine whether it is relevant to monitor for V2P message and/or configure the access stratum. The navigation system application may determine whether it is relevant to monitor for V2P message and/or to configure the access stratum, based on the WTRU location. The navigation system application may determine whether it is relevant to monitor for V2P message and/or to configure the access stratum, based on whether the WTRU is indoors, close to a street, etc. The WTRU may use sources of information to augment the position information. For example, the WTRU may use sources of information to augment the Wi-Fi nodes around, network indications, etc. The network and/or RSU may determine (e.g., may determine for the WTRU) whether it may be relevant to monitor V2P messages and/or configure the WTRU to monitor V2P messages by activating and/or deactivating V2P monitoring. The network and/or RSU may determine whether it may be relevant to monitor V2P messages and/or to configure the WTRU via RRC and/or other higher-layer signaling.

[0142] A WTRU may be configured with a sleep cycle. For example, a V2P enabled WTRU may be configured with a sleep period and/or V2P reception period. The sleep period and/or the V2P reception period may be changed. For example, the sleep period and/or the V2P reception period may be changed based on a change in contextual information and/or other event. The sleep period and/or the V2P reception period may be a frequency at which the WTRU may monitor for and/or processes V2P messages. [0143] A WTRU may be configured to operate in a sleep cycle and/or to process, configure, and/or modify messages. For example, a pedestrian WTRU may operate according to a sleep cycle to save power (e.g., IDLE and/or connected DRX). The pedestrian WTRU may monitor for messages during the on period of the sleep cycle. The sleep cycle may be determined by configuration and/or the sleep cycle may be modified based on events. The frequency with which the pedestrian WTRU may monitor and/or receive broadcast messages within the on duration may be based on configuration and/or may be modified. A pedestrian WTRU may operate using one or more sleep cycles. A pedestrian WTRU may receive V2P broadcast messages during the on period of the sleep cycle. During the on period of the sleep cycle, the pedestrian WTRU may receive and/or process one or more messages destined to the pedestrian WTRU. During the on period of the sleep cycle, the pedestrian WTRU may receive and/or process a portion of the messages destined to the pedestrian WTRU. During the on period of the sleep cycle, the pedestrian WTRU may receive and/or process one or more messages with a periodicity. For example, the WTRU may wake up every second for a period of 500ms, and/or the WTRU may process V2P messages every 10ms during the wakeup time. The sleep cycles and/or the periodicity of message processing may be determined by a configuration coming from the network. The sleep cycles and/or the periodicity of message processing may be determined by a configuration coming from the operator OAM. The sleep cycles and/or the periodicity of message processing may be determined by a configuration coming from the application or application server. The sleep cycles and/or the periodicity of message processing may be determined by a configuration statically configured in the WTRU.

[0144] The pedestrian WTRU may change one or more sleep cycle parameters. For example, the pedestrian WTRU may change the on and off duration, sleep cycle period, etc., sleep cycle parameters. The pedestrian WTRU may change message processing periodicity. For example, the pedestrian WTRU may change message processing periodicity, based on a specific event, action, and/or occurrence. The event may be a reception of a V2P message (e.g., from a vehicle, from an RSU, or from an e B). The V2P message may be communicated via the Uu interface. The event may be a change in location of a vehicle, of the pedestrian WTRU, and/or of another pedestrian WTRU. The event may be a determination that the location of the pedestrian WTRU may be within some target area. The event may be a determination that a vehicle poses a collision risk. The event may be a change in location characteristics of the pedestrian WTRU (e.g., indoor/outdoor, inside a vehicle, etc.). A sleep cycle may increase as a result of receiving a V2P message from a vehicle.

[0145] The pedestrian WTRU may process messages with a periodicity of PI . For example, the pedestrian WTRU may process messages with a periodicity 10ms. The pedestrian WTRU may receive a V2P message from a vehicle which may be sending messages with a periodicity P2. For example, the pedestrian WTRU may receive a V2P message from a vehicle which may be sending messages with a periodicity of 1ms. The pedestrian WTRU may change the message processing periodicity of the pedestrian WTRU to P2. For example, the pedestrian WTRU may change the message processing periodicity of the pedestrian WTRU to P2 based on a determination of a potential danger. The determination of a potential danger may be performed by the V2P application residing in the pedestrian WTRU and/or elsewhere in the network.

[0146] The application layer within the WTRU may instruct the lower layers to modify the message processing periodicity and/or the sleep cycle. The pedestrian WTRU may inform the network of the change in periodicity.

[0147] The application layer within the WTRU and/or the application server may instruct the e B to change the message processing periodicity and/or the sleep cycle parameters for the specific WTRU. For example, the application layer within the WTRU and/or the application server may instruct the eNB to change the message processing periodicity and/or the sleep cycle parameters for the specific WTRU in the case of a V2P over the Uu interface. The eNB may instruct the change at the WTRU using mechanisms. The sleep cycle may increase. For example, the sleep cycle may increase as a result of approaching higher risk area.

[0148] A trigger may change the message processing periodicity. For example, the trigger to change the message processing periodicity may be that the pedestrian WTRU has changed location and/or has moved into an area where it may determine that it may receive V2P messages (e.g., may receive V2P messages more frequently). The pedestrian WTRU may determine that it may receive V2P messages (e.g., may receive V2P messages more frequently), based on the application layer. For example, the trigger to change the message processing periodicity may be that the pedestrian WTRU has moved from indoor to outdoor, or vice-versa. The trigger, to change the message processing periodicity, may be that the pedestrian WTRU has moved closer to, or farther from, an intersection. The trigger to change the message processing periodicity may be that the pedestrian WTRU has moved from the front of a building to the sidewalk or from the sidewalk to the front of the building. The trigger to change the message processing periodicity may be that the pedestrian WTRU has moved into a crowded parking lot.

[0149] A WTRU may efficiently transmit a broadcast. A WTRU may transmit for a crowd of WTRUs. For example, a WTRU may transmit for a crowd of nearby WTRUs. One or more WTRUs may be configured to transmit on behalf of a crowd of WTRUs. For example, one or more WTRUs may be configured to transmit on behalf of a crowd of WTRUs in an efficient broadcast transmission. The WTRU may determine the neighboring WTRUs. For example, the WTRU may determine the neighboring WTRUs via direct discovery (e.g., LTE D2D or other, such as Bluetooth) and/or via network signaling. The WTRU may determine whether the WTRU may be transmitting. For example, the WTRU may determine whether the WTRU may be transmitting on behalf of the neighboring WTRUs. The WTRU may determine whether the WTRU may be transmitting via a negotiation step and/or via network configuration. The WTRU may transmit V2P messages on behalf of one or more (e.g., a set of) neighbor WTRUs. The WTRU may indicate on the broadcast message of the WTRU that the WTRU may be transmitting on behalf of a crowd of WTRUs. For example WTRU may indicate on the broadcast message of the WTRU the number of WTRUs, position, direction, speed, and/or status of a WTRU in the crowd and/or of the entire crowd itself.

[0150] A WTRU may determine when it may be relevant to transmit information. For example, a WTRU may determine when it may be relevant to transmit V2P information. A WTRU may transmit a message and/or activate a transmission. For example, a WTRU may transmit a V2P message and/or activate a V2P transmission on a condition that no "equivalent message" has been received from another WTRU and/or from the network. A WTRU may transmit a V2P message and/or activate a V2P transmission on a condition that that no

"equivalent message" has been received from another WTRU and/or from the network within a certain period of time. Two or more messages may be defined as "equivalent" if they convey (e.g., substantially convey) the information relevant for the purpose of the messages. The WTRU may determine that the messages may be equivalent when one or more of the following conditions may be satisfied for parameters indicated in the messages and/or associated with the messages. The WTRU may determine that the messages may be equivalent when a distance between geographical locations may be within a threshold. The WTRU may determine that the messages may be equivalent when a difference in speed and/or velocity (e.g., or a modulus thereof) may be within a threshold. The WTRU may determine that the messages may be equivalent when a period between time stamps may be within a threshold. The WTRU may determine that the messages may be equivalent when a type and/or status of a user (e.g., a pedestrian, vehicular, passenger, etc.) may be the same. The WTRU may determine that the messages may be equivalent when a type of message may be the same.

[0151] A WTRU may determine to withhold transmission of a message and/or to deactivate a transmission. For example, a WTRU may determine to withhold transmission of a V2P message and/or to deactivate V2P transmission on a condition that an equivalent message may not be received from another WTRU and/or from the network. For example, a WTRU may determine to withhold transmission of a V2P message and/or to deactivate V2P transmission on a condition that an equivalent message may not be received from another WTRU and/or from the network within a certain period of time. The WTRU may determine when it may be relevant to transmit and/or activate transmission of V2P messages. For example, the WTRU may determine when it may be relevant to transmit and/or activate transmission of V2P messages for an efficient broadcast transmission. The WTRU may determine when it may be relevant to transmit V2P messages using on or more of the examples described herein for determining when it may be relevant to monitor for V2P messages. For example, the WTRU may use the location of the WTRU and/or the information provided by the WTRU's navigation system to determine whether the WTRU may start transmitting V2P messages. The WTRU may determine whether it may start transmitting V2P messages, based on some configured policy. The WTRU may configure its access stratum to activate and/or to deactivate transmission of V2P messages. The WTRU may be configured to withhold transmission of V2P messages when the WTRU may be located in a mall, a stadium, etc. The WTRU may determine that the WTRU may transmit V2P messages when the WTRU may be within a predefined distance of an intersection, and/or while the WTRU's speed and/or direction indicate that the user may be moving towards that intersection. Such determination may be provided by the application layer to the lower layers, and may make use of the WTRU's navigation system, location information (e.g., through GPS, OTDOA, or other), altitude information, radar, or commination with nearby WTRUs and/or sensors.

[0152] The WTRU may activate and/or deactivate transmission of messages at the same time that the WTRU may activate and/or deactivate monitoring of messages. For example, the WTRU may activate and/or deactivate transmission of V2P messages at the same time that the WTRU may activate and/or deactivate monitoring of V2P messages. The WTRU may activate and/or deactivate transmission of V2P messages at a time other than when the WTRU may activate and/or deactivate monitoring of V2P messages. For example, the WTRU may maintain a state (e.g., a single state) for activation and/or deactivate of V2P operations.

[0153] The WTRU may determine when to use a PC5 interface versus a Uu interface. For example, the WTRU may be configured to determine when to use a PC5 interface (e.g., direct communication) and/or the Uu interface (e.g., communication via network) to transmit V2P messages. The WTRU may be configured to determine when to use a PC5 interface (e.g., direct communication) and/or the Uu interface (e.g., communication via network) to transmit V2P messages for efficient broadcast transmissions. The WTRU may be configured with one or more policies (e.g., a set of policies) from higher layers. For example, the WTRU may be configured with one or more policies (e.g., a set of policies) from a V2X server and/or from the network. The WTRU may determine (e.g., based on the configured parameters) whether to transmit V2P over the PC5 interface and/or over the Uu interface. The WTRU may determine whether to transmit V2P over the PC5 interface and/or over the Uu interface, based on the configured parameters. For example, the WTRU may be configured to transmit over the Uu interface and/or the PC5 interface when moving at a predefined speed (e.g., when the WTRU is on a motorcycle). The WTRU access stratum may be configured by a V2X application to determine whether it is should be transmitting over the Uu interface or the PC5 interface.

[0154] The WTRU may be configured to transmit using the PC5 interface and/or Uu interface. For example, the WTRU may be configured to transmit using the PC5 interface and/or Uu interface based on the WTRU's location. If the WTRU is close to an intersection, and/or if the WTRU determines that it may be in the trajectory of a vehicle, the WTRU may transmit using the PC5 interface. The WTRU may transmit using the PC5 interface in order to rely on faster transmission and/or lower latency times associated with the PC5 interface (e.g., in comparison to the Uu interface). When the WTRU is farther from the intersection, the WTRU may be configured to transmit using the Uu interface. The same policy (e.g., location and/or vicinity of a vehicle or intersection) may be used by the pedestrian WTRU to select the resources or transmission parameters (e.g., sidelink pools) to transmit with. For example, the WTRU may be configured to transmit using a higher priority pool when it determines that it may be close to an intersection and/or in the vicinity and/or trajectory of a vehicle.

[0155] The WTRU may determine whether to transmit using the PC 5 interface and/or the Uu interface. For example, the WTRU may determine whether to transmit using the PC5 interface and/or the Uu interface, based on whether the estimated latency until transmission of the message may be initiated and/or completed. The estimated latency until transmission of the message may include the use of the PC5 and/or the Uu interface. The WTRU may transmit over the interface that minimizes the latency. The WTRU may transmit over the interface that minimizes the latency for certain types of messages. The estimated latency may take into account (e.g., for the Uu interface case) the RRC state of the WTRU (e.g., idle and/or connected), whether the timing advance timer may be expired, the time until the next available SR resource, etc. The WTRU may determine whether to transmit using one or more of the PC5 interface and/or the Uu interface, based on the transmission power, total energy, and/or transmission time required for the transmission of the message. The WTRU may select the interface that may minimize the quantity. The WTRU may determine whether to transmit using the PC5 interface and/or the Uu interface, based on a priority associated with the message. For example, the WTRU may determine that certain messages (e.g., messages that have high priority) may be transmitted over both interfaces. Messages that have high priority may include messages indicating an impending collision, etc.

[0156] The WTRU may determine whether to transmit using the PC 5 interface and/or the Uu interface based on an indication from the network. For example, the WTRU may be indicated to transmit and/or retransmit a message over the PC5 interface following an indication from the network that messages may not be broadcast by the network. The indication that messages may not be broadcast by the network may be received by the physical layer, MAC layer, and/or higher layer signaling. The WTRU may re-attempt transmission over the Uu interface. For example, the WTRU may re-attempt transmission over the Uu interface after a timer (e.g., a timer started upon reception of the indication) expires and/or after reception of an indication from the network that transmission over the Uu interface may resume. The WTRU may determine whether to transmit using the PC5 interface and/or the Uu interface, based on the estimated traffic intensity (e.g., traffic load) over the PC5 interface. For example, the WTRU may transmit over the PC5 interface unless, or until, the estimated load exceeds a threshold. The load may be estimated by determining a number of received messages. For example, the load may be estimated by determining a number of received messages per unit of time and/or a proportion of resources used within a predefined period. The WTRU may determine whether to transmit using the PC5 interface and/or the Uu interface, based on the time elapsed since the transmission of a buffer status report related to the message(s). For example, the WTRU may transmit over the PC5 interface after a timer (e.g., a timer started upon transmission of the buffer status report) expires. The timer may be stopped upon reception of a grant allowing transmission of the message over the Uu interface. The WTRU may determine whether to transmit using the PC5 interface and/or the Uu interface, based on the time elapsed between the transmission of the message over the Uu interface and the reception of the corresponding message over Uu interface. The WTRU may determine whether to transmit using the PC5 interface and/or the Uu interface, based on whether the WTRU is accessing the network requesting resources for V2X

transmissions resources and/or until the WTRU receives dedicated configuration from the network. The WTRU may determine whether to transmit using the PC5 interface and/or the Uu interface, based on whether the WTRU is in coverage and/or out of coverage of the network. For example, the WTRU may determine to transmit over the PC5 interface when the WTRU is out of coverage, and the WTRU may determine to transmit over the Uu interface when the WTRU is in coverage.

[0157] A WTRU may configure and/or modify the transmission periodicity of the WTRU. For example, a pedestrian WTRU may modify its transmission periodicity between two or more configured values. The pedestrian WTRU may modify its transmission periodicity between the two or more configured values, based on actions, events, and/or occurrences.

[0158] Although features and elements are described above in particular combinations, one of ordinary skill in the art will appreciate that each feature or element can be used alone or in any combination with the other features and elements. In addition, the methods described herein may be implemented in a computer program, software, or firmware incorporated in a computer- readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (transmitted over wired or wireless connections) and computer- readable storage media. Examples of computer-readable storage media include, but are not limited to, a read only memory (ROM), a random access memory (RAM), a register, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and removable disks, magneto-optical media, and optical media such as CD-ROM disks, and digital versatile disks (DVDs). A processor in association with software may be used to implement a radio frequency transceiver for use in a WTRU, WTRU, terminal, base station, RNC, or any host computer.

Claims

What is Claimed:

1. A wireless transmit/receive unit (WTRU) comprising:

a processor configured to:

identify contextual information of the WTRU, wherein the contextual information of the WTRU comprises location information of the WTRU and movement information of the WTRU;

receive a configuration, wherein the configuration comprises one or more possible radio configuration parameters;

determine a set of one or more radio configuration parameters to implement from the one or more possible radio configuration parameters indicated in the configuration based, at least in part, on the identified contextual information of the WTRU; and

configure the WTRU using the determined set of radio configuration parameters.

2. The WTRU of claim 1 , wherein the WTRU is a vehicle-to-everything (V2X) WTRU.

3. The WTRU of claim 1, wherein the location information of the WTRU comprises longitude and latitude information of the WTRU.

4. The WTRU of claim 1, wherein the movement information of the WTRU comprises speed, direction of heading, or acceleration information of the WTRU.

5. The WTRU of claim 1, wherein the processor is configured to receive the configuration via an application server located on the network.

6. The WTRU of claim 1, wherein the processor is configured to receive the configuration within a predefined distance of another WTRU.

7. The WTRU of claim 1, wherein the processor is configured to transmit the contextual

information to a network, road side unit (RSU), or application server.

8. The WTRU of claim 1, wherein the processor is configured to receive the configuration from an e B via a Uu interface.

9. The WTRU of claim 8, wherein the processor is configured to receive the configuration via the Uu interface, based on the configuration being broadcast from the eNB.

10. The WTRU of claim 1, wherein the processor is configured to receive the configuration from another WTRU via a PC5 interface.

11. The WTRU of claim 1, wherein the contextual information of the WTRU comprises status information of the WTRU.

12. The WTRU of claim 1, wherein the processor is configured to identify contextual

information of another WTRU, wherein the contextual information of the other WTRU comprises location information of the other WTRU and movement information of the other WTRU.

13. The WTRU of claim 12, wherein the processor is configured to determine the set of one or more radio configuration parameters from the one or more possible radio configuration parameters indicated in the configuration, based, at least in part, on the identified contextual information of the other WTRU.

14. A method, comprising:

identifying contextual information of a wireless transmit/receive unit (WTRU), wherein the contextual information of the WTRU comprises location of the WTRU and movement information of the WTRU;

receiving a configuration, wherein the configuration comprises one or more selectable radio configuration parameters;

selecting a set of one or more radio configuration parameters to implement from the one or more selectable radio configuration parameters indicated in the configuration based, at least in part, on the identified contextual information of the WTRU; and

configuring the WTRU using the determined set of radio configuration parameters.

15. The method of claim 14, wherein the WTRU is a vehicle-to-everything (V2X) WTRU.

16. The method of claim 14, wherein the location information of the WTRU comprises longitude and latitude information of the WTRU.

17. The method of claim 14, wherein the movement information of the WTRU comprises speed, direction of heading, or acceleration information of the WTRU.

18. The method of claim 14, wherein the configuration is received via an application server located on the network.

19. The method of claim 14, wherein the configuration is received within a predefined distance of another WTRU.

20. The method of claim 14, wherein the contextual information is transmitted to a network, road side unit (RSU), or application server.

21. The method of claim 14, wherein the configuration is received from an e B via a Uu

interface.

22. The method of claim 21, wherein the configuration is received via the Uu interface, based on the configuration being broadcast from the eNB.

23. The method of claim 14, wherein the configuration is received from another WTRU via a PC5 interface.

24. The method of claim 14, wherein the contextual information of the WTRU comprises status information of the WTRU.

25. The method of claim 14, wherein the processor is configured to identify contextual

26. The method of claim 25, wherein the processor is configured to determine the set of one or more radio configuration parameters from the one or more selectable radio configuration parameters indicated in the configuration, based, at least in part, on the identified contextual information of the other WTRU.