V2X Communication Technology: Field Experience and Comparative Analysis

This paper studies the requirements of Electronic Toll Collection systems in regard to their demand for interoperable 5.8 GHZ Dedicated Short Range Communication (DSRC) systems. It first gives an overview of DSRC standardization. It then describes the technical concepts of the physical layer of 5.8 GHz DSRC, and gives examples of roadside and vehicle equipment and advanced solutions for future multilane electronic toll collection systems.

<div class="section abstract"> <div class="htmlview paragraph">This SAE Standard specifies a message set, and its data frames and data elements specifically for use by applications intended to utilize the 5.9 GHz Dedicated Short Range Communications for Wireless Access in Vehicular Environments (DSRC/WAVE, referenced in this document simply as “DSRC”), communications systems. Although the scope of this Standard is focused on DSRC, this message set, and its data frames and data elements have been designed, to the extent possible, to also be of potential use for applications that may be deployed in conjunction with other wireless communications technologies. This Standard therefore specifies the definitive message structure and provides sufficient background information to allow readers to properly interpret the message definitions from the point of view of an application developer implementing the messages according to the DSRC Standards.</div> </div>

Dedicated short range communication (DSRC) is the key component in intelligent transportation systems (ITS). The goal of this technology is to help driver and passengers getting multimedia services via wireless communication equipment during the movement of vehicle, so as to improve the traffic safety and enhance the transportation efficiency. The paper is focus on the DSRC baseband technical analysis and the application development. Based on the WLAN 802.11a architecture, we develop a new adaptive channel estimation algorithm that uses two kinds of feedback tracking and pilot aid to enhance wireless access ability in vehicular environments.

Vehicle-to-everything (V2X) communications have become a key enabler for future autonomous driving by providing sensing and cooperation abilities beyond traditional on-board sensors. The main candidate technologies for V2X communications are dedicated short range communication (DSRC)/IEEE 802.11p and long-term evolution (LTE), each of which has its own strengths and weaknesses. DSRC provides low-latency direct connectivity, but suffers from serious link degradation and reliability issues. On the other hand, LTE is able to provide high capacity data transmission, while its latency remains an issue due to the long transmission time interval. Integrating these two radio technologies as a heterogeneous solution is promising to complement each other and support V2X applications with differentiated service requirements. This paper proposes a service-aware radio access technology (RAT) selection algorithm that enables a heterogeneous LTE/DSRC solution, where LTE and/or DSRC are selected according to services. Each vehicle is assumed to be equipped with both LTE and DSRC interfaces. The heterogeneous solution selects RAT based on the services requirements with consideration of the networks performance. The solution is implemented with integration of the C-ITS standard and validated through the OMNet++ and SUMO based network simulator. A see-through scenario, where a fleet of vehicles require real-time video data sharing to assist efficient driving, is considered. The simulation results demonstrate that the proposed approach outperforms the purely DSRC approach significantly and is able to simultaneously support safety message transmission with low latency, video streaming with high bandwidth requirements, and other applications with different service requirements.

Results of system simulations on link level for vehicle-to-vehicle (v2v) communications are presented in this paper. The corresponding system model complies with the IEEE802.11a wireless LAN standard, which is expected to play a major role in future inter-vehicle communications (IVC) systems. Only the physical (PHY) layer is considered for the simulations. A realistic channel model is integrated in the system model. Different characteristic road traffic scenarios, such as a motorway and an urban road are investigated. Both, line-of-sight (LOS) and non-line-of-sight (NLOS) situations are taken into account. For the simulations only the link between two vehicles is considered. Interference resulting from other vehicles is neglected. The results are characteristic curves of the bit error rate (BER) and packet error rate (PER) over the signal to noise ratio (SNR) at the receiver. I. INTRODUCTION The road traffic density is continuously increasing. The re- sulting large number of vehicles on the streets leads to congestion and accidents, which cause delays, costs, injuries and sometimes death. It is therefore a challenging task to cope with all the upcoming traffic. A necessary step to solve the problem is to provide the driver in time with specific route dependent information. This includes mobility-relevant information (e.g. the actual traffic conditions on the whole route) as well as safety-relevant information (e.g. detailed information about the road and traffic conditions in the vicinity of the vehicle). Thereby, the primary goal is to improve the traffic flow, avoid accidents and shorten journey lengths. Moreover, the increasing demand for mobile computing will have the future automobiles being equipped with high data rate access to the internet. Various multimedia applications, such as video on demand, games, email, etc. will be available. To provide automobiles with this large amount of informa- tion, inter-vehicle communications will be one necessary tool (1), (2). It is expected that in the future all vehicles on a road are able to communicate with each other and to share data. As the number of participants in such a dynamic communication scenario is fluctuating rapidly, IVC will be organised in an ad-hoc network manner (3). North American authorities allocated 75MHz of spectrum in the 5GHz band for dedicated short-range communications (DSRC). DSRC is expected to enable delivery of large amount of data to vehicles at short ranges via v2v and vehicle-to- roadside (v2r) wireless links (3). The Federal Communications Commission (FCC) report and order 03-324 is adopting licen- sing and service rules for the DSRC standard, especially focu- sed on v2v and v2r communication (4). Currently, the Ameri- can Society for Testing and Materials (ASTM) and the Institute of Electrical and Electronics Engineers (IEEE) are working on an evolution of the IEEE802.11a wireless LAN standard for v2v and v2r communications termed IEEE802.11p (Wireless Access in Vehicular Environments, WAVE) (5), (6). The PHY layer of IEEE802.11p will be similar to that of IEEE802.11a. Results of IVC link level simulations, which are performed on the basis of IEEE802.11a (7), are presented in this paper. For the investigations a base-band model of IEEE802.11a is implemented in the development environment System Studio (8). The model contains solely the PHY layer of the system. In order to get reasonable results a realistic model of the inter-vehicle transmission channel is used for the system simulations (9). Different characteristic road traffic scenarios, such as a motorway and an urban road are investigated. Both, LOS and NLOS situations are taken into account. For the simulations only the link between two vehicles is considered. Interference resulting form other vehicles is neglected. For each scenario the BER and PER over the SNR at the receiver are determined. The 6Mbit/s and 12Mbit/s transmission mode of IEEE802.11a are analysed. The channel model and the system model are described in the following two sections. Subsequently, the results of the simulations are presented.

Wireless Power Transfer (WPT) services require a communication network to ensure that the power transfer from grid to vehicle is carried out in a precisely controlled manner such that it is fast, safe and most efficient. A comprehensive scalable WPT ecosystem will comprise of not only vehicles and charging controllers but will also include multiple value chain providers such as charge station operators, power generation and grid management companies and vehicle manufacturers etc. So a communication system should not only address the immediate first-hop communication between the vehicle and charging controller but also provide a robust end-to-end communication solution that addresses scalability, real-time response characteristics, in a cyber-secure manner. This paper summarizes the combined efforts of Clemson University and Cisco Systems related to the development of a communication system for stationary, quasi-dynamic and dynamic WPT under DOE FOA 0000667 that addresses these aspects. The implementation used Dedicated Short Range Communication (DSRC) technology as the wireless technology and applied the Fog computing framework as the base for the overall architecture. This approach provided 1) ultralow latency communication between the vehicle and the infrastructure required by WPT real-time control loop, and 2) edge analytics for vehicles and grid components and interaction with WPT cloud. The design of the communication system includes: 1) Identification of data characteristics for the charging session, 2) Implementation of wireless link based on DSRC, 3) Design of network/transfer protocol over WSMP used by DSRC radios and 4) Design of infrastructure and back end architecture based on Fog computing. In addition, this paper presents a discussion of the characteristics of this network architecture and the lessons learned during this project.

The Industrial Internet of Things (IIoT) is the use of Internet of Things (IoT) technologies in manufacturing. The vehicular ad hoc networks (VANETs) are a typical application of IIoT. Benefiting from Dedicated Short‐Range Communication (DSRC) technology, vehicles can communicate with each other through wireless manner. Therefore, road safety is able to be greatly improved by the broadcast of safety messages, which contain vehicle’s real‐time speed, position, direction, etc. In existing DSRC, safety messages are broadcasted at a fixed frequency by default. However, traffic conditions are dynamic. In this way, there are too many transmission collisions when vehicles are too dense and the wireless channel is underused when vehicles are too sparse. In this paper, we address broadcast congestion issue in DSRC and propose lightweight adaptive broadcast (LAB) control for DSRC safety message. The objectives of LAB are to make full use of DSRC channel and avoid congestion. LAB meets two key challenges. First, it is hard to adopt a centralized method to control the communication parameters of distributed vehicles. Furthermore, the vehicle cannot easily acquire the channel conditions of other vehicles. To overcome these challenges, channel condition is attached with safety messages in LAB and broadcast frequency is adapted according to neighboring vehicles’ channel conditions. To evaluate the performance of LAB, we conduct extensive simulations on different roads and different vehicle densities. Performance results demonstrate that LAB effectively adjusts the broadcast frequency and controls the congestion.

Vehicular Ad-Hoc Networks (VANETs) play a significant role in Intelligent Transportation Systems (ITS). The vehicles exchange awareness and safety information with surrounding vehicles using IEEE 802.11p Dedicated Short Range Communications (DSRC) and IEEE 1609 Wireless Access in Vehicular Environment (WAVE)-based short-range communication networks in 5.9 GHz band. These safety messages include periodic beacon messages and event driven emergency messages that are shared in Control Channel (CCH). By collecting these messages and applying clustering we can facilitate new applications like network congestion control, traffic control etc. The partitioning-based clustering methods like the k-means, the Partitioning Around Medoids (PAM) are well known in data science. This paper focuses on understanding the message clustering intuitively. The clustering quality is measured using silhouette plot and average silhouette width. The simulation is carried out in OMNeT++ and SUMO-based Veins framework. A simple approach using a package called RInside is explored for fast prototyping of machine learning algorithms in OMNeT++ simulations.

The research of vehicular networks has been studied for many years. In actual life, there are a few implementations of V2X communication system, majority of them are extremely expensive. Most importantly, detailed insight implementation procedure hasn't been provided for researches. In this paper, an efficient V2X communication system based on the IEEE 802.11p/1609.X protocol stack, also known as the Wireless Access in Vehicular Environment (WAVE) standard has been designed. In this system, a Dedicated Short Range Communication (DSRC) unit using low-cost and commercial hardware which can support the vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications is developed. Some specific driver adjustments based on the IEEE 802.11a driver are taken to assure compliance with the IEEE 802.11p protocol. Besides, the development of networking layer protocol is accomplished based on IEEE 1609.3. Furthermore, three safety applications and a performance evaluation subsystem have been developed on this platform. The subsystem can test the comprehensive performance of the communication unit in terms of Packet Loss Rate (PLR), throughput and end-to-end delay. Meanwhile enormous experiments are conducted to evaluate the performance of the communication prototype and different scenarios were designed to validate the practical function of the safety applications.

Dedicated Short Range Communications (DSRC) is a wireless communication standard intended for high speed secure communication between vehicles and the infrastructure. In order to overcome the limitations that vehicular environment imposes such as high mobility, IEEE published the 802.11p amendment widely known as Wireless Access in Vehicular Environment (WAVE). To the best of our knowledge, most of the WAVE stack implementations and studies that are carried out till now are simulator based. This paper majorly focuses on the implementation of IEEE 1609 WAVE /DSRC stack on a Linux based system that forms the backbone of vehicular communication. It dives deep into the changes and the development of new modules that have to be made in Linux kernel to cater the need for vehicular communication. We also discuss in brief about the various challenges faced and design decisions that were made in this process. Finally, we conclude by depicting the performance of our developed stack in comparison with commercially available stack in terms of packet losses.

This research addresses reliability issues of safety applications in Intelligent Transportation Systems (ITS) that use Dedicated Short Range Communication (DSRC) in Wireless Access in Vehicular Environments (WAVE) systems. Reliability of such applications is affected not only by the usual environmental effects of wireless communication, but also potentially by malicious act. The case of constant and random jamming and their impact on safety applications are investigated under consideration of the data rates used. It is shown that the most important message, the Basic Safety Message (BSM), which is transmitted on a dedicated safety channel can be jammed, resulting in safety application failure. To mitigate against jamming a communication scheme based on redundant channel is used that utilizes channels with higher power ratings for communicating data with BSM-equivalent content, while not deviating from existing standards. The impact of channel and message redundancy for different data rates is investigated. Considering the two jammer types, it is shown that the introduction of redundancy overcomes the impact of jamming attacks. Furthermore it is demonstrated that application reliability increases inverse to the data rates of the channels. Analysis shows that DSRC safety applications that use redundant communication can overcome jamming attacks if data rates of 3Mbps and 6Mbps are used, while 12Mbps communication is not advisable.

Vehicular networks face a typical quandary in their requirement for communications that are at once secure and private. While the messages broadcast between vehicles and between vehicles and the supporting infrastructure must be authentic and non repudiable, they must also ensure the vehicle driver's anonymity. The Dedicated Short Range Communications (DSRC) framework's Wireless Access in Vehicular Environments (WAVE) application development architecture mandates the use of Public Key Infrastructure (PKI) mechanisms for securing messages, consequently compromising the driver's expectation of privacy. In this paper, we propose a WAVE-based protocol for the secure and anonymous propagation of vehicle safety broadcast messages. A hybrid key infrastructure approach is put forth which combines the use of a shared network authorization key for devices that require anonymity and PKI for devices that do not.

Modern vehicles are configured to exchange warning messages through IEEE 1609 Dedicated Short Range Communication (DSRC) over IEEE 802.11p Wireless Access in Vehicular Environment (WAVE). Essentially, these warning messages must associate an authentication factor such that the verifier authenticates the message origin via visual binding. Interestingly, the existing vehicle communication incorporates the message forward-ability as a requested feature for numerous applications. On the contrary, the vehicle security infrastructure is vulnerable to message forwarding i.e., Messages seem to originate from a malicious vehicle (due to non-detectable message relaying) instead of the actual message sender. We introduce the non forward-able authentication to avoid an adversary coalition attack scenario. These messages should be identifiable with respect to the immediate sender at every hop. We propose to utilize immediate optical response verification in association with the authenticated key exchange over radio channel. These optical responses are generated through hardware means, i.e., A certified Physically Unclonable Function (PUF) device embedded on the front and rear of the vehicle.

DSRC Based Sensor-Pooling Protocol for Connected Vehicles in Future Smart Cities

Message dissemination issue in Vehicular ad hoc networks (VANETs) has been extensively studied both by computer simulations and experimental testbeds. Dedicated Short Range Communications (DSRC) technology has been standardized and used extensively as the main mechanism to support the message dissemination in VANETs. Nevertheless, other alternatives such as 3G/4G and WLAN have also been proposed to further assist with the message dissemination in VANETs. Due to the ubiquity of the smartphones, in this paper, we propose to leverage the use of smartphone to disseminate message in VANETs. An android-based system that uses WLAN ad-hoc technology is proposed. The feasibility and performance of the proposed system are investigated by simulations and the evaluation results show that given the high penetration of smartphones, the message dissemination can be done via the smartphones. Although the delay performance of the proposed system is inferior to DSRC-based system, the proposed system could still be very useful especially during the deployment stage of the DSRC technology (when the penetration rate of the technology is low).