Communication delay guarantee for IEEE 802.11p/wave Vehicle networks with RSU control

Abstract

The standard 802.11p/wave provides communication facilities to many vehicle applications. The safety application for vehicle collision avoidance is one of the most attractive issues for industrial and research concerns. However, medium access protocols proposed by standards and research works are not dedicated to this kind of real time applications. A deterministic medium access is needed to guarantee communication delay constraints. Thus, we propose an extension of the CSMA/CA medium access defined in the standard. It is an enhancement of the collision resolution procedure to be deterministic. An infrastructure with Road Side Units (RSUs) is used to manage the secured zone. It is also to complete and control communication for collision detection approach. This new protocol has the main advantage of low bandwidth utilization, low latency and deterministic communication. We have also proposed a worst case analysis model to predict communication delay in order to verify the real time constraints. Simulations are made to perform the efficiency of our protocol relative to other ones.