Traffic Safety Message Forwarding Mechamism Based On Roadside Unit

Vehicular traffic safety messages to reduce traffic accidents and ease traffic congestion has very important role,but the vehicle moving fast,network topology changes frequently and network broadcast storm easily lead to traffic safety message transmission failed.In this paper,we consider the use of fixed roadside units in the city road to forward traffic safety information,and put forward a traffic safety news broadcast protocol based on RSU.The core idea of RABP protocol is to combine V2V communication and V21 communication to efficiently and rapidly deliver traffic safety messages.RABP protocol is divided into two stages,that is,the optimal RSU selection phase and RSU broadcasting phase.In the first stage,the union game based method to find the optimal relay vehicle nodes until the discovery of RSU exists around the vehicle,and then use based on multiple attribute decision making of optimal RSU selection algorithm to find optimal RSU,the vehicle traffic safety information give first priority to the transmission to the RSU.In the second stage,the use of RSU intelligent broadcasting algorithm of traffic safety messages to cover the range of vehicles,traffic safety will also pass a message to around RSU through a wired network.In this paper,through the general simulation platform EXata and traffic flow simulator VanetMobiSim to verify the proposed RABP protocol,and Simulation of different scenarios of the AODV protocol,performance of OLSR protocol and RABP,comparative analysis the performance index of the three protocols.The simulation results show that RABP has a greater improvement in the packet delivery ratio and the average time delay of the traffic safety messages.RABP protocol can be well applied to urban road traffic safety information transmission.