Hovering Based Information Dissemination And Broadcast Approach Of VANET In Road Intersection

VANET as an emerging research branch of the mobile network, has received theattention of governments and academics. Based on the V2V communication and V2Rcommunication, it constitutes an integrated network platform of information sharingandtransmission.InformationbroadcastanddistributionisthebasicsupportofVANETthat broadcasts diferent kinds of information to users as their demand to meet the in-dividual needs, which is important and meaningful for promoting the development ofVANET.For location related messages,we studied the regional information dissemi-nation and hovering in the entrance of highway and abnormal road.Based on theseproblems,this paper analyzed diferent trafc fow model and studied information dis-tribution and transmission according the characteristics of diferent models.First,based on the T-shape road structure in ShangHai, we studied the infromationbroadcast process and proposed the relay node selection algorithm in the entrance ac-cording to the Poisson model, to alleviate the network load and improve the broadcastefciency.On the basis of neighbor nodes’ state,the selection algorithm estimates theutility of each node as the next relay node and determined the next relay node.At thesame time, we also studied the situations when the connectivity problem happened.Then, a more detailed analysis of macroscopic trafc fow model and microscopicmodel,i.e. trafc wave model and car following model,is given.The trafc wave modelcan well refect the trafc state change when trafc congestion happened.So,accordingtothischaracteristics,wedesignedtheinformationbroadcastschemewiththetransmis-sion of the trafc wavefront.Car following model considered the interaction betweenthe vehicles to describe the change of the vehicle’s velocity and acceleration infu-enced by the ahead vehicle. Therefore,we derived the vehicle state transmission speed of inter-vehicle on basis of the optimal inter-vehicle distance and just noticeable difer-ence.Then the scheme that the information broadcasting is in accord with the vehiclestate transmission was presented.