SDDV: scalable data dissemination in vehicular ad hoc networks

Abstract

An important challenge in the domain of vehicular ad hoc networks (VANET) is the scalability of data dissemination. Under dense traffic conditions, the large number of communicating vehicles can easily result in a congested wireless channel. In that situation, delays and packet losses increase to a level where the VANET cannot be applied for road safety applications anymore. This paper introduces scalable data dissemination in vehicular ad hoc networks (SDDV), a holistic solution to this problem. It is composed of several techniques spread across the different layers of the protocol stack. Simulation results are presented that illustrate the severity of the scalability problem when applying common state-of-the-art techniques and parameters. Starting from such a baseline solution, optimization techniques are gradually added to SDDV until the scalability problem is entirely solved. Besides the performance evaluation based on simulations, the paper ends with an evaluation of the final SDDV configuration on real hardware. Experiments including 110 nodes are performed on the iMinds w-iLab.t wireless lab. The results of these experiments confirm the results obtained in the corresponding simulations.

Doppler Shift Compensation Schemes in VANETs

“…Recent researches have highlighted significant challenges to VANET deployment [7]. These challenges include inadequate bandwidth to meet the conditions imposed by the safety and nonsafety applications [8], low packet delivery rate (PDR) arising from congestion in dense traffic networks [9], and high BER due to Doppler shift degradation caused by high node mobility [10]. Whereas the first two challenges have adequately been addressed by introducing the cyclic prefix (CP) and enhanced distributed channel access (EDCA) mechanism, Doppler shift lacks such direct elimination methods in high-mobility networks [11].…”