COTraMS: A Collaborative and Opportunistic Traffic Monitoring System

Traffic monitoring and control are becoming more and more important as the number of vehicles and traffic jams grow. Nevertheless, these tasks are still predominantly performed by visual means using strategically placed video cameras. For more effectiveness, proposals to improve traffic monitoring and control should consider automated systems. In this paper, we propose the Collaborative and Opportunistic Traffic Monitoring System (COTraMS), which is a system that monitors traffic using available IEEE 802.11 networks. COTraMS is collaborative because user participation is essential in defining the vehicle movement and opportunistic because it uses existing information. To evaluate the performance of COTraMS, a prototype is implemented using an IEEE 802.11 b/g network. Measurements from a real public wireless network in Rio de Janeiro, Brazil, demonstrate the possibility of obtaining traffic conditions with our proposed monitoring system. In addition, we analyze COTraMS via simulation to evaluate its performance in scenarios with a larger number of vehicles. The comparison of the obtained results with data obtained from Global Positioning System shows high accuracy in detecting both the position of the vehicle and the estimation of the road condition, using a simple architecture and a small amount of network bandwidth.