Dedicated Short Range Communication System Research Articles

Evaluating Signal Preemption Requests in Utah Using Vehicle-to-Everything Dedicated Short-Range Communication Equipped Snowplows

At the start of the 2019 to 2020 snow season, vehicle-to-everything (V2X) systems using dedicated short-range communication (DSRC) were placed on Utah Department of Transportation snowplows and traffic signal controllers on selected state routes. This study was conducted to understand the overall impacts of snowplows using V2X DSRC to request signal preemption. Roadside units (RSUs) were deployed on five corridors throughout the Salt Lake metropolitan area. Similar routes without RSUs were selected as a control and were used in the analysis to quantify results. Each snowplow on these corridors was equipped with an onboard unit (OBU). Based on data collected, analysis was performed on both traffic signal performance and vehicle performance data. Within the traffic signal performance analysis, it was found that the V2X DSRC system was utilized often, with snowplows requesting preemption in more 50% of the occasions they approached a signalized intersection. Of those requests, signal controllers granted preemption in over 80% of cases. On average, signal controller coordination was affected for less than 5 min. The vehicle performance analysis found that the snowplows on equipped routes had travel speeds that were less affected when there was snow than on corresponding not-equipped routes. Vehicle crash data also showed that there was a greater decrease in crashes on equipped routes than not-equipped routes. Anecdotal evidence gathered from snowplow drivers indicated that snowplows stopped less when using signal preemption. Drivers also noted a benefit to overall snow removal operations on corridors equipped with the V2X DSRC system.

Algorithm development for Vehicle-To-Vehicle (V2V) communication

This paper presents the development of an algorithm for Vehicle-to-Vehicle (V2V) communication, a crucial technology in Intelligent Transportation Systems (ITS) that holds significant potential for enhancing road safety and traffic efficiency. One of the most common types of vehicle collisions occurs at intersections, particularly those without traffic lights. This study focuses on creating a V2V algorithm designed to prevent collisions in such scenarios. The findings were presented through visual simulations that depict various scenarios involving vehicles approaching an intersection. The algorithm follows a two-step process: Firstly, it utilizes Dedicated Short-Range Communication Systems (DSRCS) to accurately estimate the distance between vehicles. Leveraging this distance information, the algorithm dynamically adjusts the speed of each vehicle. The algorithm’s performance is assessed using Convolutional Neural Networks (CNN), which enables a comprehensive evaluation of its reliability and efficiency in V2V communication. The algorithm demonstrates notable enhancements in the reliability and efficiency of V2V communication. This paper serves as a validation of the feasibility of developing more advanced V2V communication algorithm and potentially making significant contributions to the advancement of ITS.

Radio Frequency Fingerprint-Based DSRC Intelligent Vehicle Networking Identification Mechanism in High Mobility Environment

In recent years, Dedicated Short-Range Communication (DSRC) vehicle interconnection technology has achieved mature development and broad applications, which is the key Vehicle to Everything (V2X) technology to realize transport intelligence. However, the openness of wireless transmission and the mobility of wireless terminals cause the identification mechanism of the DSRC system to face serious security threats. A radio frequency fingerprint (RFF)-based identification method can better resist the identity attack and spoofing by extracting the hardware characteristics formed by the differences of electronic components to authenticate different devices. Therefore, in this paper a novel RFF identification mechanism is proposed for IEEE 802.11p protocol-based DSRC intelligent vehicle networking devices suitable for a high mobility environment, in which the preamble field features of physical layer frames are extracted as device fingerprints, and the random forest algorithm and sequential detection method are used to distinguish and authenticate different devices. The experiment and simulation results demonstrate that the identification accuracy rates of the eight DSRC modules in the low-speed LOS and NLOS experimental states and up to 70 km/h high-speed simulations all exceed 99%, illustrating that this method has important application value in the field of identity authentication of V2X devices in high-speed scenarios.

Simulations of vehicular optical wireless communication systems and comparisons with DSRC systems.

Optical wireless communication (OWC) has been proposed as a complementary technique to radio frequency (RF) communications for vehicular applications. OWC systems can be categorized into two types based on the transmitters: the first one is the light-emitting diode (LED)-based OWC system, and the second is the laser diode (LD)-based OWC system. Simulations of both types of OWC systems are presented in this paper. To simulate the OWC systems precisely, outdoor experiments of OWC systems have been done and the measurements of background noise are applied in the simulations. In terms of the LED-based OWC system, the impulse responses are obtained by an improved ray tracing algorithm. To reduce the computational complexity, visibility graphs are applied in the improved ray tracing algorithm. Compared with the brute force algorithm, our improved algorithm is able to reduce the computational complexity from O(n3) to O(n2log⁡(n)), where n is the number of mobile terminals. In LD-based OWC systems, the performance and stability are highly dependent on the tracking system in vehicular applications. Therefore, this paper also analyzes the requirements of tracking accuracy in LD-based OWC systems. Finally, the simulated LED-based OWC system is compared with the dedicated short-range communication (DSRC) system under different traffic densities. Our experimental and simulation results have demonstrated that OWC can be a complementary technique for DSRC under conditions of high traffic density.

Field Evaluation of Connected Vehicle-Based Transit Signal Priority Control under Two Different Signal Plans

In 2017, a connected vehicle (CV) corridor utilizing dedicated short-range communication (DSRC) technology was built along Redwood Road, Salt Lake City, Utah. One main goal of this CV corridor is to implement transit signal priority (TSP) when the bus is behind its published schedule by a certain threshold. With the data generated by the transit vehicles, transmitted through the DSRC system, logged by traffic signal controller, and coupled with the Utah Transit Authority (UTA) data from transit operation system, some performance data of the TSP can be analyzed including TSP requested, TSP served, bus reliability, bus travel time, and bus running time. For providing better signal coordination to buses, the signal plan for this CV corridor underwent retiming in October 2018. This research aims to compare the TSP performance before and after the signal retiming. The field data of August, September, November, and December in 2018 were selected to perform this evaluation. Results show that the TSP served rate after signal retiming is 35.29%, which is higher than that of 33.12% before signal retiming. In addition, compared with the signal plan before October, bus reliability northbound and southbound on the CV corridor was improved by 2.4% and 1.47%, respectively; bus travel time and bus running time were reduced as well.

Crash Risk-Based Prioritization of Basic Safety Message in DSRC

Dedicated short-range communications (DSRC) is one of the key technologies enabling safety-critical applications for intelligent transportation system (ITS). Considering the significance of such safety-of-life applications, it is of utmost importance to guarantee reliable delivery of basic safety messages (BSMs). However, in accordance with a V2X network being inherently dynamic in key aspects such as vehicle density and velocity, the networking behavior of a DSRC system is usually highly complicated to analyze. In addition, the United States Federal Communications Commission (US FCC) recently proposed the so-called “5.9 GHz band innovation,” which includes a plan to reduce bandwidth for DSRC to 10 MHz at best from 75 MHz. Motivated from these challenges, the necessity of “lightening” load of a DSRC network has become essential to keep safety-related operations from performance deterioration. To this end, this paper proposes a protocol that prioritizes transmission of a BSM from a vehicle according to the level of accident risk of the vehicle. The proposed protocol uses the distance of a vehicle from a danger source as the metric to determine the priority for transmission. Our results show that this protocol effectively prioritizes the transmission opportunity for dangerous vehicles, and hence results in higher performance in terms of key metrics–i.e., average latency, packet delivery rate ( $\mathsf {PDR}$ ), and inter-reception time ( $\mathsf {IRT}$ ).

Sophisticated Spectrum Sharing Analysis: The Case of the 5.9 GHz Band

Efficient spectrum sharing is becoming more critical as the demand for wireless services increases across many industries and available bandwidth remains scarce. To respond to this need, regulators must understand inter-system interactions in specific spectrum sharing scenarios in order to make informed policy judgments. These decisions are best made through risk-informed interference analysis, rather than worst-case advocacy, as noted by De Vries (2017) and many other scholars. Nowhere is this analytic need more apparent and urgent than the 5.9 GHz frequency band. 5.9 GHz is adjacent to existing Wi-Fi spectrum and a prime candidate to enable highly-demanded wireless broadband services, but it is today allocated exclusively to Dedicated Short Range Communications (DSRC), a technology in development for vehicle to vehicle (V2V) and vehicle to infrastructure (V2I) safety and commercial communications. A sophisticated and realistic technical understanding of coexistence between Wi-Fi and DSRC is therefore central to this archetypal spectrum sharing case study – an understanding that, to date, has been lacking, leading to a nearly five-year policy stasis since the FCC initially proposed sharing for this band in 2013. This paper uses radio frequency (RF) engineering and computer science techniques to provide the necessary technical foundation for spectrum sharing policy in 5.9 GHz. Specifically, we use lab-based RF measurements as the foundation for simulation of real-world system interaction between Wi-Fi and DSRC, with a particular focus on how the presence of adjacent channel Wi-Fi impacts the performance of the crash-avoidance safety application of DSRC according to the leading strategy for sharing 5.9 GHz, known as the re-channelization plan, which is described further in this paper. Lab-based RF measurements provide actual DSRC performance impacts at different inter-system configurations, which are then anchored to a network and road traffic simulation that captures the behavior of Wi-Fi and DSRC in an actual cityscape with observed vehicular volume and movement patterns. DSRC system architects define its key performance indicator as packet error rate (PER). In this paper we build on PER and define a risk-informed metric called safety alert failure rate (SAFR) which focuses on the failure rate for packets that have an impact on safety outcomes in real world traffic scenarios, consistent with risk-informed spectrum policy analysis. We use an open-source vehicular traffic simulator known as Veins (Vehicles in Network Simulation) to observe the DSRC SAFR for over 20,000 vehicles traveling during rush hour in Bologna, Italy, with the presence of Wi-Fi interference. This approach is data-intensive and enables calculation of SAFR in scenarios where vehicular traffic makes collisions probable – which is the inter-system interaction of greatest concern for spectrum policymakers. In so doing, we provide a path forward for policy in this important frequency band. We observe that DSRC SAFR is not impacted by the presence of Wi-Fi traffic in the adjacent channel. We also observe that the SAFR is above the levels deemed by DSRC architects to be harmful to system performance in the majority of locations simulated; however, since this result is not due to Wi-Fi interference, we conclude that it is most likely attributed to DSRC system instability in high vehicular traffic scenarios. We perform a number of checks to demonstrate the robustness of these conclusions. Our results therefore suggest that regulators can successfully enable Wi-Fi use of the 5.9 GHz band without impacting DSRC safety efficacy. This finding provides the necessary technical foundation for policy in an important frequency band, and provides a valuable case study for rigorous analysis in spectrum sharing scenarios more generally.

Application of Advanced Communication Technologies in the Improvement of Traffic Safety

Incorporation of advanced info-communication technologies into vehicular environment currently captures a large attention by numerous investigators, telecommunications operators, traffic safety regulatory institutions, car industry manufacturers and other interested participants. In this paper, we overview of some prospective wireless communication technologies, such as the DSRC (Dedicated Short Range Communications) and advanced LTE (Long Term Evolution) mobile communication systems, which are considered as two promising candidates to support future traffic safety applications in vehicular environment is presented. The communication requirements of some active traffic safety applications are pointed. A summary of various types of communications for intelligent VCS (Vehicular Communication System) applications is given. Some future directions and challenging issues for implementing traffic safety applications are also discussed. Our goal is to demonstrate the growing impact and importance of modern communication technologies in achieving future traffic accident-free roads.

Vehicular Networking in the TV White Space Band: Challenges, Opportunities, and a Media Access Control Layer of Access Issues

With the increase of wireless data traffic demand, supplementing dedicated short-range communications (DSRC) with additional spectral opportunities becomes very important. In many countries, due to the switchover from analog to digital television, a significant portion of the television (TV) band has been released for opportunistic cognitive access. Therefore, one possible solution to the spectrum scarcity problem in the DSRC band is to offload a portion of data traffic to the TV white space (TVWS) band. However, expansion of vehicular networks to the TVWS by means of cognitive radio technologies causes novel challenges such as random channel availability, strict protection of incumbent spectrum users, and dealing with interference among heterogeneous cognitive networks. In this article, we outline the challenges and opportunities involving TVWS access for vehicular networks, with an emphasis on media access control (MAC) layer issues. Numerical results of the DSRC system augmented with a TVWS cognitive module are also presented.

Physical layer design for image transmission between WiMAX/DSRC system

In order to enhance and meet the demands of vehicular communication several authors have proposed the possibility of convergence between two different technologies. In context to this, authors of this paper proposed a novel combined hybrid infrastructure for efficient vehicular communication. The novelty of this approach is the vehicular standard, i.e. dedicated short range communication (DSRC) can be converged with the existing wireless mobile communication network, i.e. Worldwide Interoperability for Microwave Access (WiMAX) technology. Authors critically explored the two different systems in terms of their physical layer, frame structure and packet format. As these technologies are based on the Institute of Electrical and Electronics Engineers therefore we do not intend to change the standards, instead we are attempting to change only a few possible parameters which can be configured to create a bridge between the physical layers of the mentioned technologies. By using this bridge we are able to establish the image transmission between WiMAX and DSRC system. The MATLAB simulation result shows that the hybrid system can be implemented to establish communication in vehicular network.

Vehicular ad-hoc network simulations of overtaking maneuvers on two-lane rural highways

The objective of this paper is to evaluate the effectiveness of a dedicated short-range communication (DSRC)-based wireless vehicle-to-vehicle (V2V) communication system, called the overtaking assistant, devised for improving safety during overtaking (also referred to as passing) maneuvers on two-lane rural highways. Specifically, the paper examines the influence of vehicular kinematics (vehicle speeds, accelerations and distances), driver behavior (drivers’ perception/reaction time and overtaking rate), and DSRC characteristics (power settings, communication range, packet errors, sensor errors, and estimation inaccuracy) on the effectiveness of DSRC systems in predicting unsafe overtaking maneuvers. To this end, the paper utilizes a microscopic traffic simulator called VEhicles In Network Simulation (VEINS) that supports the simulation of wireless communication protocols in Vehicular Ad-hoc NEtworks (VANETs). 18,000 overtaking maneuvers – with roughly 10,000 collision maneuvers – were simulated to consider heterogeneity in vehicular kinematics, driver behavior, and DSRC performance. The overtaking assistant predicts whether a collision will occur and warns the driver before the maneuver begins. A descriptive analysis followed by a multivariate analysis (using binary discrete outcome models) of the simulated data reveals that the majority of collisions that could not be detected were due to the vehicles being out of communication range for the communication power settings used in the simulation. Packet errors, or failed communications, at a rate of up to 50% did not have a significant influence on the ability to detect collisions. These results suggest that the most important step in paving the way toward advanced driver assistance systems for rural highway overtaking maneuvers is to broaden the communication range of DSRC devices.

Modeling and performance analysis of dynamic spectrum sharing between DSRC and Wi‐Fi systems

AbstractThe Notice of Proposed Rulemaking 13‐22 released by Federal Communications Commission unlocks the Dedicated Short Range Communication (DSRC) spectrum for Wi‐Fi availability, which undoubtedly brings unpredictable effects to the new‐emerging vehicular applications and services. To efficiently harmonize the spectrum operation between DSRC and Wi‐Fi networks, several dynamic spectrum‐sharing schemes are already proposed to improve the spectral efficiency over a limited bandwidth situation and as well to satisfy the ever‐increasing demand for bandwidth resource. Different from most previous literature that mainly focused on the performance analysis of cellular‐network‐centric spectrum sharing, we aim to analyze the performance of the mainstream dynamic spectrum‐sharing schemes specially designed for the coexistence of DSRC and Wi‐Fi networks against various combinations of network parameters through a hybrid network model and performance indicators. We employ the Poisson point process to model a hybrid network where DSRC vehicles and Wi‐Fi devices coexist, and introduce the performance indicators of spectrum efficiency and data rate to assess the utility of different spectrum sharing candidates. Through the presented hybrid model and performance indicators, we collect extensive numerical and simulation results to investigate four typical spectrum allocation schemes for DSRC and Wi‐Fi coexistence, that is non‐sharing scheme, original sharing scheme, and Qualcomm's and Cisco's proposals, respectively. The results show that the dynamic spectrum sharing in the 5.9‐GHz band can significantly raise the performance of Wi‐Fi network without excessively degrading the DSRC system, and especially the Cisco's proposal prefers to protect the DSRC profit while the Qualcomm's draft favors Wi‐Fi exclusively. Copyright © 2016 John Wiley & Sons, Ltd.

Improved scheme for the problem of anti‐fading of DSRC systems in IEEE 802.11p environments

Vehicular communication for accident avoidance is an important application defined in the IEEE 802.11p. One of the challenges of vehicular communications in the current IEEE 802.11p standard is the complex and rapidly changing channel conditions. In this study, the author focusses on the vehicle-to-vehicle channels under the IEEE 802.11p standard and point out that there exist two different kinds of fading. Then, a new dedicated short range communication (DSRC) system with two improved methods is proposed for the weak performance of anti-fading of current system in IEEE 802.11p environments. The author adopts matrix spectral transformation method to replace least squares algorithm in spectral temporal averaging (STA) scheme proposed by Fernandez to further mitigate the negative effects of DSRC system caused by fast time-varying fading. Meanwhile, the author also proposes a spectral keying method to further enhance its ability of anti-frequency-selective fading. The final simulation results show that compared with STA and other methods, the improved scheme shows better performance on mean square error, bit error rate and packet error rate, which is promising for practical applications.

Compact single-layer circularly polarized antenna for short-range communication systems

Dedicated short-range communications (DSRCs) is a short-to-medium range wireless protocol designed for automotive systems. This article describes the development of a one-layer compact left-hand circularly polarized antenna with a footprint and characteristics suitable for on-board-unit antenna of a DSRC system. The size of the developed prototype is 40 × 40 × 1.55 mm3 and exhibits a circularly polarized gain of about 4.68 dBc with a cross polarization discrimination of about 22.5 dB. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1843–1846, 2014

Controlling Congestion in Safety-Message Transmissions: A Philosophy for Vehicular DSRC Systems

Dedicated short-range communication (DSRC) is a powerful new technology that allows vehicles to communicate with each other. [DSRC is the U.S. vehicle communication technology operating in the 5.9-GHz Intelligent Transportation Systems (ITS) band; the analogous technology in Europe is called Cooperative ITS, and the band is referred to as ITS G5.] In particular, they exchange safety messages that allow collision threats to be identified and avoided. Channel congestion is a significant challenge because it causes safety messages to be lost and introduces latency in threat modeling at the application layer. This article describes a philosophy of DSRC congestion control, based on maximizing channel throughput via distributed control of the rate at which each vehicle transmits safety messages. It then defines a specific adaptive control algorithm, a weighted version of the LInear MEssage Rate Integrated Control (LIMERIC) algorithm. Weighted-LIMERIC has provable stability, convergence, and weighted fairness attributes. NS-2 simulation results that demonstrate these attributes are also presented.

하이패스 DSRC 자료를 활용한 고속도로 오프라인 경로통행시간 추정기법 개발

Korea Expressway Corporation has been utilizing vehicles equipped with dedicated short range communication (DSRC) based on-board equipment (OBE) for collecting path travel times. A path based method (PBM) estimates the path travel time using probe vehicles traveling whole links on the path, so it is not always possible to obtain sufficient samples for calculating path travel time in the DSRC system. Having this problem in utilizing DSRC for travel time information, this study attempted to estimate path travel time with the help of a link based method (LBM) and examined whether the LBM can be used for obtaining reliable path travel times. Some comparisons were made and identified that the MAPE difference between the LBM and the PBM estimates are less than 3%, signaling that LBM can be used as a proxy for PBM in case of sparse sample conditions. Some limitations and a future research agenda have also been proposed.

COMPACT PLANAR UWB ANTENNA WITH BAND NOTCH CHARACTERISTICS FOR WLAN AND DSRC

In this paper, a compact ultra-wideband microstrip-fed annular ring antenna with band notch characteristics for wireless local area network (WLAN) and dedicated short-range communication (DSRC) is proposed. The proposed antenna comprises an annular ring patch and a partial ground plane with a rectangular slot. The notched frequency band is achieved by etching a partial annular slot in the lower portion of the ring radiator. The centre frequency and bandwidth of the notched band can be controlled by adjusting the width and position of the annular slot. Measured results show that the proposed antenna achieved an impedance bandwidth of 3{10.6GHz with a notched frequency band centred at 5.5GHz. Compared to the recently reported band-notched UWB antennas, the proposed antenna has a simple conflguration to realize the band notch characteristics to mitigate the possible interference between UWB and existing WLAN & DSRC systems. Furthermore, a symmetric radiation patterns, satisfactory gain and good time domain behaviour except at the notched frequency band makes the proposed antenna a suitable candidate for practical UWB applications.

Chip Design of an 1 V RF Receiver Front-End for 5.8-GHz DSRC Applications

An 1 V RF receiver front-end applying in 5.8 GHz DSRC (Dedicated Short Range Communication) systems is presented in this paper. The proposed chip includes a current-reused LNA, a folded Giber cell mixer, a Colpitts VCO, and an IF Gm-C bandpass filter. The measured results of the chip show an input return loss of 20 dB, a conversion gain of 29 dB, a double-side band (DSB) noise figure (NF) of 5 dB, and a third-order intercept point (IIP3) of −24.4 dBm. The on-chip oscillator shows the measured tuning range of 5.17–5.98 GHz and phase noise of −118.5 dBc/Hz at 1 MHz offset from the 5.8 GHz carrier. The proposed receiver front-end is fabricated in a 0.18 μm CMOS process with a power consumption of 27.6 mW from a 1 V supply voltage. The chip area including PADs is 1.75 × 1.2 mm2.

Monolithic patch antenna for dedicated short‐range communications

Dedicated short-range communications (DSRCs) is a novel short- to medium-range wireless protocol designed for automotive use. The DSRC signals are circularly polarised and allocated in the 5.8 GHz band. Described is the development of a monolithic and compact patch antenna with left-hand circular polarisation intended for the on-board unit equipment of a DSRC system. The 40×60×2.455 mm fabricated prototype exhibits a circularly-polarised gain of about 5.52 dBc with a cross-polar discrimination of about 20 dB.

Detection Spacing of DSRC-Based Data Collection System for Real-Time Highway Travel Time Estimation

A DSRC (Dedicated Short-Range Communication)-based traffic data collection system has been introduced to enhance the accuracy of real-time traffic information. However, due to the lack of studies for the DSRC system on interrupted flow condition, there is no installation guideline of DSRC RSEs on the national highways in Korea. This study presented an appropriate spacing of DSRC RSEs for the national highways based on the accuracy of traffic information and the required minimum sample size. By analyzing the field data collected on the national highways, the optimal spacing of DSRC RSEs was selected for each type of road. According to the result, the optimal spacing for controlled-access highway was different from that for multi-lane road and urban and suburban arterial. It implies that detection spacing should be determined considering the type of road. These results would be utilized as a guideline for installing DSRC RSEs on the national highways.