Research On Path Selection Algorithm Based On IoV In The Traffic Congestion

With living standards of urban residents improving rapidly,the number of vehicles per person keeps on increasing.For the sake of traffic roads shortage and increasing number of vehicles,it is easier to lead to traffic jams.Thus a path selection algorithm should not only provide navigation services to customers,but also alleviate road traffic congestion overall.In the thesis,it mainly studies on how to utilize the information acquisition and interactions of the vehicle network system,and the path navigation under the circumstance of traffic congestion.Then the path selecting algorithm proposed in this thesis,gives proper and distinct routes for different vehicles.Therefore it can prevent all vehicles from running on the same route.Finally this method can reduce the average traveling time of vehicles in the whole area.And the main work is as follows:(1)A Cooperative Vehicle Infrastructure System for traffic jams is proposed.It includes the configurations of communication nodes and schemes.Then a scheme of traffic information collecting and data processing is designed,and the RSU(Rode Side Unit)is used to calculate the average speed of vehicles,then the system center gathers the information of rode conditions.When the traffic jam occurs,the system can use the path selection algorithm based on congestion situations.Finally the WAVE/DSRC communication scheme is used to send route information to the vehicles.(2)OP-RA(Based on Offline Parameters Rerouting Algorithm)algorithm is proposed for traffic congestion condition.The algorithm is divided into two parts.In first part,a genetic algorithm is used to compute OP(Offline Parameters),which is probability parameters of RA(Rerouting Algorithm)stored at RS(Rerouting Selection)points.It costs a large amount of time.In second part,RA is run on line at RS points and allocates a new path to a vehicle according to the random probabilities called OP,and information of the vehicle's location and destination,which is transmitted through the IoV(Internet of Vehicles)communication system between vehicles to RS points.In order to improve the response efficiency,the procedure of this part is relatively simple.(3)The effectiveness of OP-RA algorithm is verified in the VSimRTI platform simulating IoV system.In the VSimRTI,traffic simulator SUMO and network simulator ns-3 are used to construct scenarios of middle and heavy traffic jam.Through simulation results,the parameters of the genetic algorithm for calculating OP,which are recombination,mutation and replacement operators as well as the Variable Mutation Operator,are determined.Then OP-RA algorithm and the traditional path selection algorithm are compared and analyzed in two simulation scenarios.The results show that OP-RA algorithm is more suitable for traffic congestion and improves the average travelling time and decreases the CO2 emission of vehicles.