Theoretical Interference Analysis of Inter-vehicular Communication at Intersection with Power Control

Interference problems caused by congestion of vehicles at intersections or on highways may significantly affect vehicle-to-vehicle (V2V) communications, especially for active-safety assistance systems due to the importance of emergency information. In this paper, we propose a theoretical interference model of V2V communications at an intersection that uses transmission power control method. To evaluate and address the interference problem at an intersection, we derived an analytical expression of the outage probability of a typical vehicle at an intersection and provide guidelines for an optimal power control method, which cannot be obtained through simulations. We model the location of vehicles in queueing segments and running segments separately and analyze their interference based on a stochastic geometry approach. In our model, a simple power control method is used: the transmission power of each vehicle is determined by the status of the vehicle, i.e., stopping or running. By changing the transmission power of vehicles in queueing segments, we can mitigate the interference received at vehicles running closer to an intersection. By using the theoretical results, we obtain an optimal power control method, which can balance the trade-off between the outage probabilities of vehicles in queueing segments and running segments. We validated our analytical results and the effect of the power control on V2V communications through numerical experiments.