Joint Awareness and Congestion Control in Vehicular Networks

In vehicular networks, vehicles frequently broad-cast vehicle states information to track the movement of their neighbors. A large number of vehicles get access to the shared channel resources to broadcast their states information, which may lead to channel congestion. The existing channel congestion solutions mainly focus on the media access control layer state to optimize channel resource utilization, without considering the impact of the physical layer on successful packet reception performance. In this article, we propose a packet reception model to represent the successful reception rate of state packets under the influence of interference signals and noise, and design an application-specific utility function. This utility considers the states of the physical layer and the media access control layer to balance reducing the physical layer interference and meeting application requirements. We then propose a distributed joint power and rate control algorithm that uses on-demand mode to allocate channel resources to meet the safety application requirements of each vehicle. The simulation results show that our work can effectively prevent channel congestion and improve the safety performance of vehicles in different driving scenarios.