Simulation And Research On Routing Protocols For Vehicular Ad Hoc Networks Under The Urban Street Scenes

In recent years,with the improvement of living standards,the demand for vehicles in the society is also getting larger and larger.As a result,the rapid increase of vehicles leads to an endless stream of traffic problems.But these problems have been effectively allleviated as more and more vehicles are beginning te be equipped with these smart products with the upgrading of intelligent industrialization and the application of Internet of Things technology.Vehicular Ad hoc Networks provid a network for Intelligent Transportation system so that these products can send messages to each.Not all the traditional wireless routing proticols are suitable for this network because of its fast-moving environment.So the focus of this paper is to find out a wireless routing proticol which is suitable fot this network.This paper starts from the background of VANETs to introduce its functional framework and main technologies,then to introduce several kinds of common wireless routing protocols that are always used in the study of VANETs,analyze their advantages and disadvantages.This article uses SUMO to create a city street scene by first creating a road topology based on map information,otherwise,in order to make the simulation scene closer to the reality scene,setting up the vehicle travel model,following model,and the traffic lights.Based on the analysis of the mechanism and implementation method,this paper chooses the GPSR as the main vehicle routing protocol in this research,analyzes its shortcomings based on the road network model and puts forward the improved method.Finally,this study realize the simulation of improved routing protocol based on the combination of SUMO and NS2,migrate the vehicle nodes generated by sumo to NS2 which adds routing protocols for these nodes,including AODV,GPSR,and the improved routing protocol baced on GPSR.By calculating some properties like Packet Delivery Ratio,Average End-to-end Delay,and Network Throughput of data packets to analyzed and compared the protocols above.The results show that the improved routing protocol in this paper can further improve the robustness compared with the GPSR protocol when the nodes move at high-speed,which is more suitable for the VANETs.