Wireless Vehicular Communications Research Articles

On the design of tree-type ultra wideband fractal Antenna for DS-CDMA system

This article describes the CPW-feed ultra wideband tree type monopole fractal antenna and it’s backscattering. The prototype antenna is fabricated with optimized dimension. The experimental result of this antenna exhibits the ultra wideband characteristics from 5.0 GHz to 14.0 GHz. The experimental and simulated results are in good agreement. The effects of various design parameters on impedance bandwidth have also been studied in detail using EM simulator. The nature of H and E - plane radiation patterns are omni-directional and bidirectional respectively. The measured group delay is almost constant throughout band. This indicates the phase linearity. The monostatic RCS of antenna is also simulated iteration-wise for antenna and structural scattering mode. This antenna can be useful for UWB system, Microwave Imaging and vehicular radar and military high data rate wireless communications.

Performance modeling and analysis of emergency message propagation in vehicular ad hoc networks

ABSTRACTReliability and timeliness are two critical requirements of vehicle safety‐related communication services in VANETs. In this paper, we develop an analytical model to analyze the packet reception rate and end‐to‐end delay of emergency message delivery operation in a VANET environment when multihop broadcast communications are used. The model is applied to derive closed‐form expressions of the end‐to‐end delay of two popular multihop message propagation methods, that is, the farthest‐distance method and the counter‐based method. Extensive simulations are conducted to validate the correctness of the theoretic results and compare the performance of the two message propagation methods. Observations are provided for the design of efficient and robust emergency message propagation methods for vehicular wireless communication networks. Copyright © 2012 John Wiley & Sons, Ltd.

Report on Wireless Vehicular Communications [VTS News

Report on Wireless Vehicular Communications [VTS News

CodePlay: Live Multimedia Streaming in VANETs Using Symbol-Level Network Coding

The fundamental challenges of providing live multimedia streaming (LMS) services in vehicular ad hoc networks (VANETs) come from achieving stable and high streaming rate (smooth playback) for all the interested vehicles while using minimal bandwidth resources, especially under the highly dynamic topology of VANETs and the lossy nature of vehicular wireless communications. Packet level network coding (PLNC) technique has been widely accepted as an effective approach to improve the network performance during the last decade. More recent symbol-level network coding (SLNC) could further improve the efficiency of bandwidth utilization by exploiting both wireless symbol-level diversity and the benefits of network coding. In this paper, we introduce CodePlay, a new LMS scheme in VANETs that fully takes advantage of SLNC through a coordinated local push mechanism. Streaming contents are actively disseminated from dedicated sources to interested vehicles via local coordination of distributively selected relays, each of which will ensure smooth playback for vehicles nearby. Extensive simulations show that simply replacing the SLNC with PLNC technique in previous LMS schemes can not provide satisfiable user experience, and special scheme design based on the unique characteristics of SLNC proposed in CodePlay is necessary for future LMS applications in VANET.

Iterative altitude-aiding algorithm for improved GNSS positioning

The system proposed in this study relies on a WAVE P2P network, which is a proper standard to fit the vehicular environment wireless communications requests. Starting from the chance to exchange information given by this infrastructure, the possibility to improve the performance of a global navigation satellite system (GNSS) receiver based on a Kalman filter is considered. This improvement is obtained exploiting the external altitude measurements provided by other peers in the network, equipped with GNSS receivers. The topic of an altitude-aided system has been described in a previous work, that highlighted the need for a parameter that points out the effectiveness and the consistency of the computed aiding measurement, namely the altitude-aiding reliability index. A detailed analysis of this reliability index led to the development of an iterative algorithm to be used in the presence of three satellites and of a biased aiding, in order to overcome the issues related to this peculiar scenario, which is the main result of this work.

Dedicated Short-Range Communications (DSRC) Standards in the United States

Wireless vehicular communication has the potential to enable a host of new applications, the most important of which are a class of safety applications that can prevent collisions and save thousands of lives. The automotive industry is working to develop the dedicated short-range communication (DSRC) technology, for use in vehicle-to-vehicle and vehicle-to-roadside communication. The effectiveness of this technology is highly dependent on cooperative standards for interoperability. This paper explains the content and status of the DSRC standards being developed for deployment in the United States. Included in the discussion are the IEEE 802.11p amendment for wireless access in vehicular environments (WAVE), the IEEE 1609.2, 1609.3, and 1609.4 standards for Security, Network Services and Multi-Channel Operation, the SAE J2735 Message Set Dictionary, and the emerging SAE J2945.1 Communication Minimum Performance Requirements standard. The paper shows how these standards fit together to provide a comprehensive solution for DSRC. Most of the key standards are either recently published or expected to be completed in the coming year. A reader will gain a thorough understanding of DSRC technology for vehicular communication, including insights into why specific technical solutions are being adopted, and key challenges remaining for successful DSRC deployment. The U.S. Department of Transportation is planning to decide in 2013 whether to require DSRC equipment in new vehicles.

Emerging techniques for wireless vehicular communications

Emerging techniques for wireless vehicular communications

CodeOn: Cooperative Popular Content Distribution for Vehicular Networks using Symbol Level Network Coding

Driven by both safety concerns and commercial interests, one of the key services offered by vehicular networks is popular content distribution (PCD). The fundamental challenges to achieve high speed content downloading come from the highly dynamic topology of vehicular ad hoc network (VANET) and the lossy nature of the vehicular wireless communications. In this paper, we introduce CodeOn, a novel push-based PCD scheme where contents are actively broadcasted to vehicles from road side access points and further distributed among vehicles using a cooperative VANET. In CodeOn, we employ a recent technique, symbol level network coding (SLNC) to combat the lossy wireless transmissions. Through exploiting symbol level diversity, SLNC is robust to transmission errors and encourages more aggressive concurrent transmissions. In order to fully enjoy the benefits of SLNC, we propose a suite of techniques to maximize the downloading rate, including a prioritized and localized relay selection mechanism where the selection criteria is based on the usefulness of vehicles' possessed contents, and a lightweight medium access protocol that naturally exploits the abundant concurrent transmission opportunities. We also propose additional mechanisms to reduce the protocol overhead without sacrificing the performance. Extensive simulation results show that, under a wide range of scenarios, CodeOn significantly outperforms a state-of-the-art PCD scheme based on network coding.

CyberCars-2 Cooperative Cybernetic Transport System Architecture

Research on Intelligent Cooperative Systems (ICS) based on wireless vehicular communication to improve automotive safety and traffic efficiency is being promoted through initiatives such as the Vehicle Safety Communications Consortium (VSCC) and Vehicle-Infrastructure Integration (VII) in the US, SMARTWAY and Vehicle Information and Communication System (VICS) in Japan, and European R&D activities within the framework of i2010: Intelligent Car Initiative - e.g., PReVENT, CVIS, and SAFESPOT. Related standardization activities include Continuous Air Interface for Long and Medium Range (CALM) to set up a stable, globally compatible regulation framework enabling higher market impact. The Car2Car Communication Consortium (C2C-CC) supports an open, interoperable industry standard for vehicular communication based on wireless local area network (WLAN) technologies pushing for specific frequency band allocation at 5.9 GHz for critical automotive safety. This paper shows CyberCars-2’s cooperative Cybernetic Transport System (CTS) architecture compatible with C2C-CC and CALM achievements. SAFESPOT for architecture design was adopted after meeting cooperative systems benefits, i.e., improving traffic safety for more efficient logistics and response to hazards and accidents, improved road network management and control and shorter, more predictable journey times.

Wireless traffic service platform for combined vehicle-to-vehicle and vehicle-to-infrastructure communications

Vehicular wireless communications and vehicular ad hoc networks are nowadays widely identified enablers for improving traffic safety and efficiency, and a large number of suggestions for vehicle-to-vehicle and vehicle-to-infrastructure communication have been presented. The focus is typically on bilateral communication between two vehicles or on broadcasting information from one vehicle or infrastructure to vehicles in the surrounding area. In the Carlink project [1, 2] of the European Celtic program call 3 we have developed an intelligent hybrid wireless traffic service platform between cars supported by roadside wireless base stations. Communication between cars will be arranged in an ad hoc manner, supported by wireless base station connection to the backbone network whenever possible. The platform consists of a specific set of services (e.g., local road weather service and incident warning service), but a variety of services can be integrated to this kind of a system. The ultimate goal was to enhance traffic safety and smoothness, but also to generate a completely new communication entity, allowing new types of applications, services, and business opportunities. In this article we present the concept and example services of the Carlink platform. The platform simulations, field tests, and analysis show that the platform operability and efficiency are suitable for a large-scale traffic system, to be verified in the pilot system deployment.

NCTUns tool for wireless vehicular communication network researches

Several goals such as improving road safety and increasing transport efficiency are being pursued in intelligent transportation systems (ITS). Wireless vehicular communication is one technology to achieve these goals. Conducting vehicular experiments on the roads is an approach to studying the effectiveness of wireless vehicular communication. However, such an approach is costly, hard-to-control (repeat), dangerous, and infeasible when many vehicles and people are involved in the field trial. In contrast, the simulation approach does not have these problems. It is a very useful approach and complements the field trial approach. This paper presents NCTUns, an open source integrated simulation platform, for wireless vehicular communication network researches. This tool tightly integrates network and traffic simulations and provides a fast feedback loop between them. Therefore, a simulated vehicle can quickly change its driving behavior such as moving speed and direction when it receives a message from the wireless vehicular communication network. This capability is required by several novel ITS applications such as active collision avoidance systems. In this paper, we present the design, implementation, validation, and performance of this tool.

Call for Papers: Emerging Techniques for Wireless Vehicular Communications

Call for Papers: Emerging Techniques for Wireless Vehicular Communications

VTC2008-Fall in Calgary [VTS News

The 68th IEEE Vehicular Technology Conference (VTC2008-Fall) was held 21-24 September 2008 in the beautiful city of Calgary, Canada. Colocated with VTC2008-Fall was the Second IEEE International Symposium on Wireless Vehicular Communications (WiVeC). The conference brought together individuals from academia, government, and industry to discuss and exchange ideas in the fields of wireless and vehicular technology. WiVeC covered all vehicular wireless communications aspects of vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), and vehicle-to-person (V2P) communications, including implications on transport efficiency and safety, implications on automotive electronics, liability issues, standardizations efforts, and spectrum assignment. The IEEE Vehicular Technology Society (VTS) Board of Governors also held meetings to discuss policies and procedures of the VTS, the VTS's long term strategy, and many other topics, including IEEE Vehicular Technology Magazine schedules and areas of interest.

Opportunistic technique for efficient wireless vehicular communications

Vehicle-to-vehicle and vehicle-to infrastructure wireless systems are currently under development to improve the traffic safety and efficiency while providing Internet connectivity on the move. A widespread adoption of these wireless vehicular communication technologies will require efficient use of the radio channel resources. To this end, this work proposes and analyzes an opportunistic-driven adaptive radio resource manage merit (OPRAM) scheme that achieves tin- target traffic safety performance and efficiently uses the transmission and channel resources.

Call for papers: Elsevier transportation research Part C special issue on vehicular wireless communication networks for transportation

Call for papers: Elsevier transportation research Part C special issue on vehicular wireless communication networks for transportation