Research On Geographical Routing Protocol Technology For VANETs

Vehicular Ad-hoc Networks(VANET),as a key technology of the next generation of intelligent transportation systems,aims to improve road safety and promote the development of urban intelligent transportation.The traffic conditions in the urban environment are complex and changeable,which has a great impact on the information dissemination and routing selection between vehicles.Therefore,it has become a hot spot to study the routing protocols of the Internet of Vehicles adapted to the urban environment.This paper studies the routing protocol based on geographic location.Aiming at the poor quality of information transmission caused by frequent link breaks,changing topological structures,and insufficient network connectivity in an urban environment,the main work and innovations are as follows:1.Most of the existing geographic location-based Internet of Vehicles routing protocols use a location-based greedy method to select forwarding vehicles.This strategy lacks perceptual feedback on the global topology and data traffic,thereby increasing routing redundancy in the data forwarding process.To solve the above problems,a routing protocol based on traffic awareness is proposed.Abstract the global network topology as a combination of several micro topologies,and analyze the connectivity of nodes under the micro topologies.A traffic-aware model is proposed,which reflects the connectivity of nodes through effective information flow,reduces the number of route restorations,and reduces route redundancy.Evaluate the link quality and calculate the single-hop revenue based on geographic location information and vehicle motion status to improve transmission reliability.Introduce the multi-attribute utility theory to weigh the influence of connectivity and link revenue on routing,and select the best relay to establish routing.Finally,use Simulation of Urban Mobility(SUMO)to build an urban scene to simulate vehicle trajectories,and verify the routing protocol on the simulation platform Network Simulator version 3(NS-3).Simulation results show that the protocol reduces end-toend delay,packet loss rate,and improves network yield.2.Obstacles such as tall buildings and greenery in urban scenes will make nodes within the communication range unable to communicate directly,reducing network connectivity.Aiming at this problem,a UAV-assisted routing protocol is proposed to introduce UAVs into VANET to determine the shortest path while overcoming obstacles.When the link is interrupted,the UAV can be used as a candidate data relay node and relay information to the best node.In addition,UAVs can coordinate road information,use road segment area grids and node location information to implement load balancing strategies for busy nodes.In order to reduce the influence of balanced nodes on the link,the node similarity is defined as the basis for selection.Finally,the SUMO platform is used for scene simulation and the NS3 platform is used for system simulation.The simulation results show that the protocol effectively improves the data delivery rate and reduces the end-to-end delay.