Impacts of Radio Access Protocols on the Performance of DSRC based ITS Applications

This paper presents a performance comparison between the DSRC-recommended 802.11 medium access control (MAC) and a novel vehicular self-organizing MAC (VeSOMAC) protocol in the context intelligent transportation system applications. VeSOMAC is a distributed TDMA MAC protocol that relies on in-band control exchange for autonomous and self-configurable TDMA slot allocation. Detailed network and vehicular traffic models have been developed in this paper for a cooperative collision avoidance (CCA) application in highway and urban traffic intersection scenarios. Simulation results demonstrate that unlike the 802.11 style contention based protocols, VeSOMAC can offer better vehicle safety in both highway and urban intersection scenarios through smaller and bounded inter-vehicle packet latency.