Self-configuring TDMA Protocols for enhancing vehicle safety with DSRC based vehicle-to-vehicle communications

This paper presents a novel Medium Access Control protocol for inter-vehicular wireless networking using the emerging Dedicated Short Range Communication (DSRC) standards. The main contribution of the paper is the design of a self-configuring TDMA protocol capable of inter-vehicle message delivery with short and deterministic delay bounds. The proposed Vehicular Self-Organizing MAC (VeSOMAC) is designed to be vehicle location and movement aware so that the MAC slotsin a vehicle platoon can be time ordered based on the vehicles' relative locations for minimizing the multi-hop delivery delay. A novel feature of VeSOMAC is its in-band control mechanism for exchanging TDMA slot information during distributed MAC scheduling. It is shown that by avoiding explicit timing information exchange, VeSOMAC can work without inter-vehicle time synchronization. The in-band control mechanism is also used for fast protocol convergence during initial network setup and topology changes due to vehicle movements. A simulation model has been developed for comparing VeSOMACs performance with that of DSRC-recommended 802.11 MAC protocol for highway traffic safety applications.