Performance Evaluation for DSRC Vehicular Safety Communication

In this paper, an analytic model is proposed for performance evaluation of vehicular safety related services in dedicated short range communications (DSRC) system on highway. The generation and service of safety messages in each vehicle is modeled by an M/G/1 queue. But since vehicles share a medium, the service time distribution of a message needs to take contention and backoff into account. We develop a detailed semi-Markov process model to capture these effects. Furthermore this SMP interacts with the M/G/1 queue. We use fixed point iteration to capture this interaction. Based on the fixed-point solution, performance indices including transmission delay, packet delivery ratio (PDR) are derived. Analytic-numeric results are verified through extensive simulations under various network parameters. Keywords-VANET; analytic model; SMP model; safety message; performance evaluation; DSRC;