Optimal Spectrum Reuse of V2V Communications for Maximizing Average Throughput in Vehicular Ad Hoc Networks

As the evolution of future wireless technologies, vehicle-to-vehicle (V2V) communications become a critical paradigm via densely connect a lot of vehicles to improve the performance in vehicle ad hoc networks (VANETs). In this paper, we investigate the spectrum reuse optimization of V2V communications for maximizing the average throughput (AT) in VANETs. Specifically, on the basis of stochastic geometry, the homogeneous Poisson point process (PPP) is used to characterize the random distribution of V2V transmitters (V2V TXs). Then, we derive the closed form probabilities of successful transmission for both V2V pair transmission and V2V broadcasting, where the AT of V2V communications is obtained and the maximizing AT problem is analyzed with outage constraints of vehicle-to-infrastructure (V2I) communications. Further, we prove that the maximum AT exist the upper and lower bounds which are strongly correlated with V2V TX density. Finally, the optimal V2V TX density for spectrum reuse is derived in a closed form, where the AT can be maximized. Simulation analysis indicates that the maximum AT of V2V communications can be not only impacted by interference of different V2V TXs when spectrum reusing, but also lowered down by high constraints of V2I communications.