A Study on Distance-Based Multi-Hop Broadcast Scheme for Inter-Vehicle Communication

Vehicular ad-hoc network (VANET) is the one of core technologies that provides various services in intelligent transportation systems (ITS). Major services provided with multi-hop broadcasting communication are emergency warning service, forward collision warning service, and traffic information service. Frequent disconnections and low throughput due to high mobility of vehicles, fluctuant density of vehicles in traffic conditions, and interruptions of communication propagation caused by obstacles such as buildings occur in urban VANET environment. Therefore, development of a suitable multi-hop broadcast protocol that considers these characteristics of VANET should be needed. In this paper we suggest the improved distance-based multi-hop broadcast scheme for inter-vehicle communication. We apply two major approaches to exponential waiting time for faster collision avoidance dissemination of urgent messages and to high prioritized intersection waiting time for more probability of dissemination of messages toward out of intersections. In addition, we have applied the Manhattan map model and its traffic movement pattern into the simulation for more reliable performance evaluation in urban environments. As a result, the proposed scheme improves the performance as compared with basic distance-based broadcast. Our distance-based multi-hop broadcast scheme guarantees not only rapid broadcast but also reliable probability of successful transmission.