Improving communication reliability in intelligent transport systems through cooperative driving

Safety messaging among Intelligent Transport Systems relies on guaranteed timely delivery. The reliability of such a system is strongly dependent on the channel load, the channel quality and the number of hops necessary to convey information between nodes. While a lot of research has been conducted on the subject, the vehicular density is usually given, and thus, channel overloading remains a threat. In this paper, we approach the topic from the opposite direction, by allowing the vehicle traffic to be routed such that individual traveling times are minimized using the PCMA* algorithm, and analyzing the impact on the safety message dissemination. We formulate a reliability definition by introducing key parameters for analysis via the probability of timely channel access, the hidden node potential and the mean hop count. We then use simulations of real life urban scenarios that we model as communication graphs, and compare the performance of medium access with and without cooperative driving. Our results show that optimizing driving routes cooperatively with respect to driving time and fuel consumption achieves geographic distributions of the communication nodes that ensures degrees of reliability not possible in egoistic driving scenarios.