Today, there exist two types of vehicular communication technology, namely, Long Term Evolution-based vehicle-to-vehicle (LTE-V2V) and dedicated short-range communications (DSRC). Although many studies dealing with vehicular communication have been conducted, the situation where separate groups of vehicles using different communication technologies coexist has never been studied. In the coexistence situation, the communication inability issue between the vehicles using different communication technologies is raised. To resolve the problem, we propose a relaying system, called Nearest-first, where hybrid user equipments (UEs), which are equipped with both DSRC and LTE-V2V modules, are considered. When a hybrid UE receives a cooperative awareness message (CAM), the UE relays the CAM using the other communication technology. We conduct simulations in various situations incorporating realistic mobility model and road topologies. We demonstrate that the Nearest-first outperforms existing relaying schemes with the performance gain of up to 91% in terms of effective communication distances.
