Route Selection Algorithm Research And Improvement On Vehicular Network

In recent years,vehicular network as an important part of modern intelligent traffic system has attracted more and more attention,it provides dynamic communication which is between vehicle to vehicle and vehicle to base station,it has great application prospect in the modern traffic management,traffic information inquiries,mitigation of traffic congestion and prevention of traffic accidents.Vehicular network is a special Ad hoc network.Compared with the traditional Ad hoc network,the vehicular network has the characteristics of high speed mobility of vehicle nodes and the dramatic changes of the network topology.Therefore,how to improve the efficiency of data forwarding in the vehicular network has become the focus of the study.From the current point of view,the vehicular network research focus on network protocols.In the vehicular network,the vehicle nodes are moving at high speed,which leads to the dramatic changes in the network topology,combined with the building block and the instability of the wireless channel,the vehicular network link is extremely unstable and easy to break.In view of the above shortcomings,this paper proposes an AODV routing protocol based on link stability.The improved protocol is applied in the routing discovery process and the routing selection process,respectively.In the process of route discovery,the forwarding angle is calculated according to the moving direction of the vehicle node,and the nodes in the forwarding angle range are selected to reduce the broadcast redundancy in the network.In the process of establishing path,the remaining lifetime and the projection length to the destination node is calculated,and the two factors is integrated as a node's stability,the improved protocol selects the node with high stability for data forwarding,it solves the problem of the link breaking easily and improves quality of service in the network.In addition,choosing the stability link can't completely solve the problem of link's breaking according to the characteristics of vehicular network,so route repair mechanism was improved after link break.This method is combination of the source route and the local route,in the local repair,the method selects the relatively stable node between the upstream node and downstream node to avoid the happening of secondary break.The choice between source repair and local repair is determined by judging the position of the break,local repair is determined by the stability parameter between upstream node and downstream node.Data packet's transfer over the internet is more efficient and stable by improving the repair mechanism.Finally,this paper simulates the real urban traffic scenes,the improved protocol is applied in the real scenes of vehicular network,and analyses the link situation of vehicles in urban scenes.