Adaptive Messaging based on the Age of Information in VANETs

A significant challenge in 802.11p based vehicular ad hoc networks (VANETs) is that the cooperative awareness messages (CAMs) tend to experience collisions. In this paper, we propose an adaptive CAM messaging algorithm based on the emerging methodology of the age of information (AoI). Our objective is to minimize an age-penalty function in a trajectory prediction application. In our design, each vehicle will compute a local penalty which serves as an indicator on whether the CAM messaging frequency is appropriate for its mobility status; and at the same time, calculates an appropriate penalty associated with all its neighbors which serves as an indicator regarding the impact of network congestion on the trajectory prediction quality. The aggregated penalty score integrating both the local and neighboring parts will be used to adaptively control the CAM sending frequency. We are to present simulation results demonstrating that our adaptive messaging method can indeed mitigate network congestion while meet the driving safety requirements.