Performance evaluation of safety applications over DSRC vehicular ad hoc networks

In this paper we conduct a feasibility study of delay-critical safety applications over vehicular ad hoc networks based on the emerging dedicated short range communications (DSRC) standard. In particular, we quantify the bit error rate, throughput and latency associated with vehicle collision avoidance applications running on top of mobile ad hoc networks employing the physical and MAC layers of DSRC. Towards this objective, the study goes through two phases. First, we conduct a detailed simulation study of the DSRC physical layer in order to judge the link bit error rate performance under a wide variety of vehicles speeds and multi-path delay spreads. We observe that the physical layer is highly immune to large delay spreads that might arise in the highway environment whereas performance degrades considerably at high speeds in a multi-path environment. Second, we develop a simulation testbed for a DSRC vehicular ad hoc network executing vehicle collision avoidance applications in an attempt to gauge the level of support the DSRC standard provides for this type of applications. Initial results reveal that DSRC achieves promising latency performance, yet, the throughput performance needs further improvement.