Reducing the Communication Required By DSRC-Based Vehicle Safety Systems

We present an adaptive communication scheme for cooperative active safety system (CASS). CASS uses information communicated from neighboring vehicles via wireless communication in order to actively evaluate driving situations and provide warnings or other forms of assistance to drivers. In CASS, we assume that vehicles are equipped with a GPS receiver, a dedicated short range communications (DSRC) transceiver, and in-vehicle sensors. The information exchanges between vehicles include position, speed, heading, and other vehicle kinematic and dynamic information, and the information is broadcast to all neighbors within a certain communication range. The literature surmises CASS may need a vehicle to broadcast information as often as every 100 msec which may lead to channel congestion resulting in message loss rates above 20%. Here we present a new communication design scheme, supported by simulations, which indicates that CASS could be enabled by broadcasting, on average, as little as once every 500 msec.