A p-Opportunistic Channel Access Scheme for Interference Mitigation between V2V and V2I Communications

In this article, we study the co-channel problem in the 2-tier architecture of vehicular networks [i.e., vehicle-to-vehicle (V2V) communication and vehicle-to-infrastructure (V2I) communication]. The communication technology we consider here is dedicated to short-range radio communication (DSRC), cellular vehicle-to-everything (C-V2X), or a hybrid of both. The V2I communication will interfere V2V communication, and vice versa, because the roadside unit (RSU) cannot sense V2V communication during the downlink period when the V2V communication is in the coverage of RSU. We note that V2V communication will have higher priority since it conveys critical messages for road safety in connected and automated vehicle (CAV) systems. We propose a p-opportunity channel access scheme (p-OCAS) for the RSU to solve the problem. Simulation results validate the correctness of the analytical model. The investigation showed that p-OCAS can substantially minimize the interference from RSU to V2V communications according to the V2V session arrival rate to automated vehicles as well as maintain a high throughput of RSU.