Research Of VANET Routing Algorithm Based On Vehicular Community

VANET(Vehicular Ad-hoc Network)is an ad-hoc network formed among vehicles,or vehicles and road infrastructures,which facilitates the vehicles communication without the communication relays.VANET has become the most important part of ITS(intelligent transportation system).Because of the habits of the drivers,there are always some relationships among mobile features of vehicles.For example,the vehicles belong to the same district may have higher possibility of encounter.The quality of routing design of VANET is the critical for communication among vehicles.The quality of routing design directly affects the efficiency of communication.In recent years,more researchers have begun to pay attention to the affection of social relationships of vehicles on the routing design.In this thesis,the data of vehicle trajectory is analyzed and the relationships of vehicles are mined,which is the basis of community detection.Then,the results of community detection are used to improve the routing algorithm of VANET,and a simulation system is designed to evaluate the new algorithm.The detail works are listed as follows.First of all,on the basis of processed data,an algorithm,which can analyze the encounter information of vehicles based on time window,is proposed.It can obtain the relationships of vehicles based on the stability of the encounter information and friendship.Secondly,the algorithm of VANET community detection based on the relationships of vehicles is proposed.According to the relationships,it analyzes the centricity of the cluster in the network using the analytical method of social network,and thus gets the seeds of community clusters.It gives a method to calculating the similarity of the nodes based on the vehicle encounter frequency.Based on the seeds and the method,the VANET community structure would be constructed by clustering.Then,a VANET routing algorithm called C-GZER based on the vehicle community structure is proposed,which developed from the current research of VANET routing algorithm—GZER and the opportunistic network whose transmission mode is “store,carry and forward”.The simulation results show the improvement of the delivery ratio and delay under C-GZER.Finally,a simulation system is designed and implemented to simulate the routing algorithm based on VANET communities.It is consist of the data preprocessing module,the vehicle relationship digging module,the community detection module and the VANET simulation module.The former three modules implement the communities detecting.In the simulation module,SUMO is used to imitate the vehicle movement in the road network,while communications is simulated by NS2.