[STANDARDS]

Xuyu Wang and Shiwen Mao Auburn University Michelle X. Gong Google Inc.

Editors: Michelle X. Gong and Shiwen Mao

AN OVERVIEW OF 3GPP CELLULAR -TO-EVERYTHING STANDARDS

ith the growth of mobile data and devices, cellular networks have great potential to support various vehicular communication services for safety and non-safety applications. This paper presents an overview of the 3GPP cellular vehicle-to-everything (V2X) standards. We discuss various aspects of V2X standards, including types of V2X application support in 3GPP, requirements to support eV2X scenarios, different levels of automation, comparison of V2X and IEEE 802.11p, architecture, spectrum usage, and security and privacy for V2X services. Finally, we conclude this article with a review of typical V2X applications.

With the fast development of metropolitan and networking are becoming important standards developed by the European areas, city and highways have research areas for improving vehicular Telecommunications Standards Institute faced many serious socio-economic safety and optimizing traffic flow, to (ETSI) [13]. Both standard suites are based problems because of vehicular crashes enable more efficient use of transportation on IEEE 802.11p for vehicular networks and congestions. For example, the World resources, and to ensure high quality of user (VANETs). However, it has been recognized Health Organization (WHO) reports 1.25 experiences. that vehicular communications based on million traffic deaths globally in Two main vehicular communication IEEE 802.11p have several limitations when 2013; traffic jams also cause a tremendous standard suites have been developed supporting mobility and quality-of-service waste of time and fuel, which all lead to in recent years to enable information (QoS) provisioning [13]. huge economic losses [1][14]. However, exchanges between , including the Alternatively, the fast commercialization most such problems can be mitigated by dedicated short-range communications of cellular systems, such as Long-Term providing timely information to drivers (DSRC) standards in the US [12] and the Evolution (LTE), has made them useful

Photo, istockphoto.com istockphoto.com Photo, and/or vehicles. Vehicular communications intelligent transportation system (ITS)-G5 for vehicular communications. The Third

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Generation Partnership Project (3GPP) has RSU Application been developing standards for the cellular Pedestrian Server based Vehicle-to-Everything (V2X), aiming Vehicle to off er more eff ective solutions for vehicular communications. Compared with IEEE 802.11p, cellular based V2X can provide better QoS support, larger coverage, and V2P higher data rate for moving vehicles [15]. V2I Moreover, device-to-device (D2D) underlay V2V V2N communications in LTE can be leveraged for cellular based V2X applications with high reliability and low latency [15]. In this paper, we provide an overview Vehicle of 3GPP cellular V2X standards. Th e remainder of this paper is organized as FIGURE 1. Four types of V2X application support in 3GPP (i.e., V2V, V2P, V2N and V2I). follows. Section I discusses the types of V2X application support in 3GPP, while Section II introduces categories of requirements to support eV2X scenarios. In Section III, we UEs to transmit messages carrying V2V applications usually has a lower battery review diff erent levels of automation, while application information, such as traffi c capacity, and the radio sensitivity will be in Section IV, we compare V2X with IEEE dynamics, location, and vehicle attributes. lower than vehicular UEs because of the 802.11p. In Sections V and VI, we discuss To adapt to the varying amount of V2V antenna design. Th erefore, a UE supporting the architecture and spectrum usage for application information, the message V2P applications cannot send messages V2X services, respectively. We examine payloads should be fl exible. Additionally, as frequently as UEs supporting V2V security and privacy issues for V2X services 3GPP transport of messages can be applications. in Section VII, and introduce typical predominantly based on broadcasting. If V2X services in Section VIII. Finally, we the direct communication range of V2V is 4. V2N applications: A UE supporting conclude this article in Section IX. limited, the transported information can V2N applications can communicate with be forwarded by infrastructure-based V2V the application server supporting V2N I. TYPES OF V2X APPLICATION communications, such as roadside units applications, while the parties communicate SUPPORT IN 3GPP (RSU), application servers, and so on. with each other using Evolved Packet As shown in Fig. 1, there are four more Switching (EPS). V2X services are required specifi c types of V2X application support in 2. V2I applications: V2I application infor- for diff erent applications and operation 3GPP, including Vehicle-to-Vehicle (V2V), mation is transmitted from a UE supporting scenarios. Vehicle-to-Pedestrian (V2P), Vehicle- V2I applications to an RSU or locally rel- to-Infrastructure (V2I), and Vehicle-to- evant application server. Th en, the RSU or II. ENHANCEMENT OF 3GPP Network (V2N) [2]. By employing “co- application server can choose the received SUPPORT FOR V2X SERVICES operative awareness,” the above four types UE information based on diff erent trans- (EV2X) of V2X applications can be jointly used for mission modes, such as broadcast, unicast, 3GPP specifi es the Enhancement of 3GPP smarter services for end-users. For example, and multicast. Also, the RSU or application support for V2X services (eV2X) in the vehicles, pedestrians, application servers, server can transit messages to one or more following four areas: (i) Vehicles Platooning; and road infrastructure can obtain local UEs supporting V2I applications. A locally (ii) Advanced Driving; (iii) Extended environmental information by receiving relevant application server serves a particu- Sensors; and (iv) Remote Driving [3], which messages from sensors in proximity or lar geographic area, while multiple applica- are discussed in this section. other vehicles, to enable more intelligent tion servers can serve overlapped areas, In the case of vehicles platooning, vehicles services such as autonomous driving, with the same or diff erent applications. can automatically join a group of vehicles vehicle warning, and enhanced traffi c traveling together. Th e vehicles in the platoon management. We discuss these four types 3. V2P applications: V2P applications can obtain periodic information from the of V2X applications in detail below. are similar to V2V applications, and the leading vehicle for carrying on platoon V2P service information is exchanged operations, such as keeping the gap between 1. V2V applications: V2V applications between pedestrian UEs and vehicular two adjacent vehicles small (e.g., as small as allow surrounding devices to exchange UEs. V2P application information can be a sub second). Moreover, the vehicles can useful information by broadcasting, which transmitted by a V2X UE in a vehicle to operate in a distributed manner in platooning requires the user equipment (UE) to warn a pedestrian, or by a vulnerable road applications. eV2X supports vehicle subscribe to a network operator and obtain user UE to warn a nearby vehicle. Diff erent platooning, information exchange within authorization. V2V applications expect from V2V, a pedestrian UE supporting V2P the platoon, automated cooperative driving

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for short distance grouping, information TABLE 1. Comparison of V2X and IEEE 802.11p [11] sharing for limited automated platooning, information sharing for fully automated V2X 802.11p platooning, and changing driving-mode [5]. Synchronization Synchronous Asynchronous Advanced driving refers to semi- automated or fully-automated driving, where Resource Multiplexing FDM and Time Division TDM Only longer inter-vehicle distance is assumed. Across Vehicles Multiplexing (TDM) Possible RSUs and vehicles can collect information Channel Coding Turbo Convolutional from local sensors and nearby vehicles and Waveform SC-FDM OFDM share such information with each other, to Retransmission mechanism Hybrid Automatic No HARQ coordinate the maneuvers or trajectories of Repeat Request (HARQ) surrounding vehicles. By sharing a vehicle’s Resource Selection Semipersistent transmission Carrier Sense Multiple driving intention with nearby vehicles, with relative energy-based Access with Collision safer driving, higher traffic efficiency, selection. Avoidance (CSMA-CA) and collision avoidance can be achieved. Examples of advanced driving include cooperative collision avoidance (CoCA), information sharing for limited automated automation (level 2), driver assistance IV. V2X VERSUS 802.11P driving, information sharing for fully (level 1), and no automation (level 0). In this section, we examine the main automated driving, emergency trajectory These levels are distinguished by how much differences between V2X and IEEE alignment, and the provision of intersection human operator involvement is required in 802.11p [11] as summarized in Table 1. safety information for urban driving [5]. monitoring the driving environment and It can be seen that V2X is synchronous, Extended sensors allow exchange of maneuvering the vehicle. while IEEE 802.11p is asynchronous. data and information from local sensors Since synchronization allows time division or exchange of camera video data between Level 0: no automation The driving system multiplexing (TDM) and has a lower RSUs, vehicles, devices of pedestrians, and needs a human driver to monitor all driving channel access overhead, V2X achieves a V2X application servers. With extended environments and driving by themselves, higher spectral efficiency than 802.11p. sensors, vehicles can improve the perception even though assistance is available from For resource multiplexing across of the environments for more intelligent warning and intervention systems. vehicles, V2X uses FDM and TDM if decision-making. Extended sensors use Level 1: driver assistance The driving system possible, while IEEE 802.11p only employs cases include sensor and state map sharing, will provide either steering or acceleration/ TDM. Because FDM allows for a larger collective perception of environment, and deceleration assistance based on the current link budget, an extended range or more video data sharing for automated driving [5]. driving environment. All remaining aspects reliable performance at the same range can Remote driving involves enabling a V2X of driving are expected to be controlled by be achieved. Similarly, the turbo codes and application or a driver to control a vehicle the driver. SC-FCM waveform used in V2X can also remotely. This would be utilized when a Level 2: partial automation The driving achieve a longer range or more reliable remote vehicle is in dangerous scenarios or system will supply both steering and performance at the same range. for people who cannot drive themselves. acceleration/deceleration assistance based For retransmission, V2X incorporates Moreover, driving based on cloud on the current driving environment. All the Hybrid Automatic Repeat Request computing can be employed for remote remaining aspects of driving are expected to (HARQ), a combination of high-rate driving, where a cloud-based back-end be performed by the drivers themselves. forward error-correcting coding (FEC) service platform can be accessed for public Level 3: conditional automation The driving and ARQ error-control, where corrupted transportation. eV2X use cases include system can intervene in all kinds of dynamic messages are still useful for the purpose of remote driving and tele-operated support driving tasks based on the current driving recovering the original data [16]. Compared (TeSo) [5]. environment, while drivers will respond with IEEE 802.11p which does not use appropriately to a request to intervene. HARQ, V2X can achieve a higher link III. LEVEL OF AUTOMATION Level 4: high automation The driving system efficiency, longer transmission range or Level of Automation (LoA) is a measure can intervene in all kinds of dynamic driving more reliable performance. of requirements and functional aspects in tasks based on the current driving environ- For resource selection, V2X uses automation systems [3]. SAE International’s ment, whether or not drivers respond semipersistent transmission with relative new standard “J3016: Taxonomy and appropriately to a request to intervene. energy-based selection, while IEEE 802.11p Definitions for Terms Related to On-Road Level 5: full automation The driving system employs carrier sense multiple access with Motor Vehicle Automated Driving Systems” can execute all dynamic driving tasks all the collision avoidance (CSMA-CA). The V2X defines six LoAs, including full automation time under all roadway and environmental scheme optimizes resource selection by (level 5), high automation (level 4), conditions that can be managed by a choosing the close to “best” resource, with conditional automation (level 3), partial human driver. no contention overhead. On the contrary,

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IEEE 802.11p with CSMA-CA protocol TABLE 2. Comparison of V2X and IEEE 802.11p [9] selects the first “good enough” resource, thus leading to contention overhead [11]. Parameter ETSI IEEE TTA The V2X design results in a higher Operating 5.855-5.925 5.850-5.925 MHz 5 855-5 925 spectral efficiency to serve more road users. frequency range MHz MHz (Pilot system) In addition, although V2X services can coexist with IEEE 802.11p–based radio RF channel 10 MHz 10 MHz or 20 MHz Less than 10 MHz bandwidth access in adjacent channels, V2X has the additional advantages of being evolvable and RF transmit Max 33 dBm EIRP N/A 23 dBm power/EIRP scalable. This is because the cellular network can handle all V2X application services Modulation BPSK OFDM, BPSK-OFDM BPSK OFDM, scheme QPSK OFDM, QPSK-OFDM QPSK OFDM, with the same in an end-to-end 16QAM OFDM, 16QAM-OFDM 16QAM OFDM, manner, and V2X can provide an evolution 64QAM OFDM 64QAM-OFDM Option: 64QAM path from LTE to systems. 52 subcarriers Forward error Convolutional coding, Convolutional coding, Convolutional coding, V. SPECTRUM FOR V2X SERVICES correction rate = 1/2, 3/4, 2/3 rate = 1/2, 3/4 rate = 1/2, 3/4 The spectrum study of V2X services Data 3 Mbit/s, 3, 4.5, 6, 9, 12, 18, 3, 4.5, 6, 9, 12, based on LTE sidelink (i.e., the LTE D2D transmission 4.5 Mbit/s, 24 and 27 Mbit/s for 18 Mbit/s, interface) are examined in this section. rate 6 Mbit/s, 10 MHz channel Option: 24, 27 Mbit/s 3GPP should clearly specify the V2V UE RF 9 Mbit/s, spacing requirements based on adjacent coexistence 12 Mbit/s, 6, 9, 12, 18, 24, 36, 18 Mbit/s, 48 and 54 Mbit/s for evaluation of LTE-based V2V operation and 24Mbit/s, 20 MHz channel DSRC/IEEE 802.11p on adjacent carrier 27Mbit/s spacing frequencies in the 5.9GHz ITS spectrum. Media access CSMA/CA CSMA/CA CSMA/CA, In the following, we discuss the regulatory control Option: Time Slot requirements in different regions for ITS based CSMA/CA in the 5.9GHz band [9]. We also provide a Duplex TDD TDD TDD comparison of technical characteristics of method the standards for V2X services in the three regions in Table 2 [9].

1. ITU Region 1: In Europe, Intelligent A guard band of 5MHz is considered ITS radio communications (i.e., the pilot Transport Systems (ITS) is regulated in the from 5.850 to 5.855 GHz. In V2X, there system) is compatible with the described ETSI HS between 5.855 GHz to 5.925 GHz. are three types of channels, including the V2V/V2I communications and its service The spectrum utilization conditions in control channel 178, shared channels 172, requirements, as well as WAVE. the frequency range have been defined 174, 176, 180, 182, and 184, and aggregated between 5.875 GHz to 5.905 GHz by ECC channels 175 and 181. These two aggregated VI. ARCHITECTURE FOR Decision (08)01. It aims for non-safety channels, which have a 20MHz bandwidth, V2X SERVICES ITS and proposes CEPT frequency with are used to support multi-channel operations. V2X communications can be supported sub-band 5.905-5.925 GHz for the spread According to FCC 06-110, Channel 172 by over the PC5, which is a one-to-many of ITS spectrum. ECC Recommendation is intended for V2V safety communications communication interface, and by over (08)01 states that spectrum utilization to avoid and mitigate accidents, and for LTE-Uu, which is the radio interface should be in the range of 5.855 GHz to safety of life and property applications. between UE and the Evolved Node B 5.875 GHz for non-safety ITS. Moreover, For higher-power and longer distance (eNodeB) [6][7]. It can be unicast and/or a harmonized use of the frequency band communications, Channel 184 is used for Multimedia Broadcast or Multicast Service 5.875 GHz to 5.905 GHz dedicated to safety- public safety applications relating to safety of (MBMS). A UE might use these two ways related ITS applications is considered in life and property, such as road intersection of operation independently for transmitting the Commission Decision 2008/671/EC. collision mitigation. and receiving messages. For instance, a UE can only use LTE-Uu to transmit and it 2. ITU Region 2: In the US, as shown in 3. ITU Region 3: In South Korea, the is unnecessary for a UE to use MBMS for Fig. 2, IEEE Working Groups 802.11 revised ITS standardization in 2014, which reception. On the other hand, a UE can also and 1609 have standardized the V2V was published by the Telecommunications employ MBMS for reception without using architecture and protocols, named as Technology Association (TTA), supports LTE-Uu for transmission. Moreover, V2X “WAVE” (Wireless Access Vehicular vehicle communications at a maximum messages could be transmitted through Environments), which operate in the speed of 200km/h. Moreover, for inter- LTE-Uu unicast downlink and received 5.850 to 5.925 GHz range [14]. national harmonization, the advanced by a UE. In the following, we provide

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Ch.175 Ch.181 20MHz 20MHz reserved 5MHz Ch.172 Ch.174 Ch.176 Ch.178 Ch.180 Ch.182 Ch.184 10MHz 10MHz 10MHz 10MHz 10MHz 10MHz 10MHz

GHz 5.805 5.855 5.860 5.865 5.870 5.875 5.880 5.885 5.890 5.895 5.900 5.905 5.910 5.915 5.920 5.925

FIGURE 2. FCC channel allocation in 5.9GHz for V2X services. [9] V2X Application Server

EPC

V2X message

V2X message over LTE-Uu V2X message over PC5 over LTE-Uu V2X message over PC5

RSU RSU (stationary UE) (stationary UE)

FIGURE 3. V2X message transmission and reception using UE-type RSU via LTE-Uu and PC5.

examples of how the two operation modes in high-density use cases, where the UE infrastructure entities serving as UEs, i.e., over the PC5 and over LTE-Uu, could be may not be able to reliably obtain V2X such as UE-type RSUs, are incorporated. leveraged in a hybrid manner [6]. messages from distant UEs over PC5. Moreover, the UE-type RSUs and UEs are set or provided with useful information 1. PC5 based V2X communications with 2. Simultaneous LTE-Uu based and PC5 for V2X communication over PC5. MBMS reception: In this mode, V2X based V2X communications without Th e V2X Application Servers may messages are always transmitted by a UE MBMS: In this operation mode, other UEs, communicate with the UE-type RSUs. via PC5 and are received by the UE through such as UE-type RSUs, could communicate • V2X messages are obtained from other PC5 and through MBMS as well. with UEs via PC5 for both transmission UEs by the UE-type RSUs through PC5. With PC5, V2X messages are received and reception of V2X messages. Th e V2X Th e V2X application of the RSU(s) by a stationary infrastructure entity serving Application Servers can communicate with evaluates whether the messages should be as a UE, such as an RSU. Th en, the entity the UE-type RSU through a mobile network. routed to the V2X Application Server(s) can forward the application layer processed For example, LTE-Uu is required to manage over the LTE-Uu connection, if, e.g., V2X messages to a V2X Application Server the communications of V2X messages the target area is larger than its V2X using the V1 interface. For example, a beyond the direct PC5 communication communication coverage over PC5. PDN connection over LTE-Uu or other range. Based on such hybrid use of LTE- Th e target area and the size of the area type of connection can be used. Th e V2X Uu and PC5-based V2X communications, are determined by the V2X Application application server processed messages can MBMS broadcast of downlink data Server(s), where the V2X messages are be distributed to UEs through MBMS. transmissions could be negligible. distributed. To determine the distribution In this operation mode, the mobile Fig. 3 is a high-level example of this of V2X messages and the target area, network can deliver information from an operation mode. Th is operation mode the V2X Application Server could extended range. It also fulfi lls the require- includes three components [6]: communicate and coordinate with other ment for soft safety or strengthens more V2X Application Servers. advanced driving assistance applications. • To off er adequate coverage to the • V2X downlink messages are sent by Th is mode is helpful for combined sources vehicular traffi c infrastructure, stationary V2X Application Server(s) to the RSUs,

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Patient RSU which is in the target distribution area, onboard! Clear e.g., over LTE-Uu. Th en the received V2X right lane! messages are broadcasted by RSUs based on V2X communications over PC5. RSU broadcasted V2X messages over PC5 are RSU Warning! received by UEs in the same region. Warning! Please clearlane! right In this case, a vehicle UE only operates using V2V/V2P services in the V2X communication mode over PC5. When UEs are employed as RSUs, they operate in Warning! the hybrid mode with simultaneous V2X communication over PC5 and LTE-Uu. Th e V2X communications based on both PC5 and LTE-Uu can also be implemented vehicles, RSU, and pedestrians, such as when the UE is unable to obtain a V2X vehicle position, intersection position, signal directly from distant UEs via PC5. speed, distance, and heading, can be used to Th en, the Selective IP Traffi c Offl oad predict collisions. Th e information exchange FIGURE 4. V2X safety applications. (SIPTO) can be employed to reduce the among the vehicles and RSU or pedestrian delay by UE-type RSUs for communicating can also be applied to distinguish and with local V2X Servers. locate endangered sections of roads, such 2. Privacy in V2X services: High transpar- as slippery road surfaces. Fig. 4 shows an VII. SECURITY AND PRIVACY ency will aff ect vehicle privacy by using example of V2X safety applications. In the 1. Security of V2X services: Th ere are two broadcast to send UE messages. Under this following, we examine several main V2X types of V2X application data transmission condition, the V2X service will be operated safety applications [17]. methods, which are periodic transmissions under regional regulatory requirements from vehicle UEs and event-driven and/or operator policy, whether or not such • Forward Collision Warning: Th e broadcast messages. Both of them can be privacy will happen in the V2X service. Forward Collision Warning (FCW) manipulated through the PC5 interface and Th us, it is optional to utilize the PC5 privacy application serves to alert the driver of the LTE-Uu interface [10]. mechanisms. For example, a service that is Host Vehicle (HV) in case of a predictable Th e primary purposes of V2X are safety mandated for use by a regulator may not rear-end collision with the Remote Vehicle and effi ciency, which can be achieved provide an "opt out" option [8][10]. For V2X (RV) ahead in traffi c in the same lane and through sending realtime alerts to drivers communications in the LTE-Uu mode, there direction of travel. With V2V Service, and pedestrians, including road hazards, are no additional privacy features beyond FCW helps drivers to mitigate or avoid congestion conditions, presence of emergency those of the regular LTE. rear-end vehicle collisions in the forward vehicles, etc. Th e safety message is usually In the application layer, privacy may path of travel. trusted as having been issued from a well- be supported by using credentials and • Control Loss Warning: Th e Control Loss functioning and legitimate device. identifi ers, which are not linked to long- Warning (CLW) application allows an HV In the PC5 mode, the transmitting term UE or user identifi ers. Moreover, these to broadcast a self-generated control loss vehicle UE does not know the recipients of credentials can be periodically refreshed. event to surrounding RVs. A warning will these messages in advance, and a security be generated to notify the driver, and the association establishment between UEs VIII. V2X APPLICATIONS RV will determine the relevance of the is not necessary in an advanced setting. V2X applications can be roughly classifi ed as event when such information is received. Th is is the nature of point to multipoint (i) V2X safety applications, and (ii) V2X non- • V2V Use Case for Emergency Vehicle communications with a changing set of safety applications [4]. We examine these two Warning: Th e emergency vehicle warning UEs. Th us, the current LTE security and types of applications in this section. service allows the emergency vehicle Proximity based Services (ProSe) security (e.g., an ambulance) to share its location, mechanisms may not be applicable. 1. V2X safety applications: V2X safety speed, and direction information with For the PC5 one-to-many communica- applications focus on reducing the potential surrounding vehicles, which helps the tions, no security mechanism is used in of traffi c accidents and the risk to passengers. vehicles to choose a safe course of action, this layer. Although the data frame includes Th e majority of annual car accidents can be such as to vacate the ambulance path. fi elds relating to group keys, these fi elds are linked to intersection collisions. Drivers can • V2V Emergency Stop Use Case: V2V set to zero for PC5 based V2X communica- obtain useful information and assistance from communications can be used in the case tions. For LTE-Uu communications, the V2X applications, thus helping them avoid of an emergency stop to trigger safer LTE security mechanism for air interface collisions with other vehicles and pedestrians. behavior for other cars in the vicinity of confi dentially should be used. Moreover, the information shared between the stationary vehicle.

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• Wrong Way Driving Warning: This use IX. CONCLUSIONS case describes V2V communication This paper presented an overview of the used between two vehicles driving in 3GPP cellular V2X standards. We first opposite directions, to warn of wrong discussed types of V2X application support way driving and trigger safer behavior in 3GPP and the categories of requirements for cars in the area. to support eV2X scenarios. We then • Pre-Crash Sensing Warning: Alerts are examined different levels of automation generated by the application to vehicles and provided a comparison between V2X REFERENCES in an imminent and unavoidable collision and IEEE 802.11p. We next reviewed the [1] F. 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Engineering Research and Education Center V2X Services.” [5] 3GPP TR 22.886, “Study on enhancement of (WEREC) at Auburn University. 3GPP support for 5G V2X services.” 2. V2X non-safety applications: V2X non- [6] 3GPP TR 23.285, “Architecture enhancements safety applications mainly focus on traffic for V2X services.” efficiency and management applications [7] 3GPP TR 24.386, “User Equipment (UE) to V2X for improving the vehicle traffic flow, control function; protocol aspects; Stage 3.” [8] 3GPP TR 33.885, “Study on security aspects traffic coordination, and assistance [17]. Xuyu Wang received a M.S. degree in Signal for LTE support of vehicle-to-everything (V2X) Moreover, they also provide updated services (Release 14).” and Information Processing from Xidian local information, maps, and space and/ [9] 3GPP TR 36.785, “Vehicle to Vehicle (V2V) University, Xi’an, China in 2012 and is now services based on LTE sidelink; User Equipment or time-related messages. V2N traffic flow pursuing a Ph.D. degree in the Department of (UE) radio transmission and reception (Release optimization and cooperative adaptive Electrical and Computer Engineering, Auburn 14).” University, Auburn, AL. His research interests cruise control are the two main non-safety [10] 3GPP TS 33.185, “Security aspect for LTE include indoor localization, health sensing, deep applications. support of V2X services.” learning, wireless communications, software [11] 5G Automotive Association, “The case for • defined radio, and big data. He received the cellular V2X for safety and cooperative driving,” V2N Traffic Flow Optimization: V2N Woltolsz Fellowship at Auburn University. traffic flow optimization focuses on 5GAA Whitepaper, Nov. 2016. [12] K. Abboud, H. A. Omar, and W. 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She is an editor of GetMobile, the “Vehicular networking: A survey and tutorial on and convenience for CACC vehicles, and ACM Mobile Computing and Communications requirements, architectures, challenges, standards reduces road congestion, thus improving Review, and an editor of the IEEE MMTC and solutions,” IEEE Commun. Surv. Tutor, traffic efficiency. E-newsletter. vol.13, no.4, pp.584–616, Fourth Quarter 2011.

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