An effective multi-hop broadcast control mechanism for emergency alert message in VANET

In recent years, vehicle safety application has played a more important role in Vehicle ad-hoc network (VANET). Multi-hop broadcast method is widely used in these applications to propagate emergent messages to surrounding vehicles. However, it will lead to higher packet loss rate and transmission latency while massive emergent packets make data collision occurs frequently. This paper proposes a position base broadcast module, named Broadcast Control Unit (BCUnit), in order to reduce the re-broadcast nodes and minimize emergent message conflict. This module can be easily implemented to WAVE/DSRC devices without any additional transmission overhead and explicit coordination among vehicles. The simulation results show significant progress in multi-hop delay.