Study On The Mountain Highway VANEts Mobility Model

VANETs mobility model is a description of the traffic flows, which is the basis of VANETs research and then the guarantee of traffic safety. VANETs mobility model is closely related to its application scenarios. The existing mobility models are mainly used in urban scene, but rarely applied in the mountainous scene. However, mountain highway roads is the most easy to induce traffic accidents. Therefore, in order to improve the traffic safety level of mountain highway, this paper proposes a VANETs mobility model which is applied to mountain highway.The research about models is to make the vehicle properties of mobility model in VANETs match the actual traffic flow properties. To describe the traffic flow characteristics of mountainous highways, the mobility model introduces three parameters: radius of horizontal curve, angle of horizontal curve and slope of the highway. According to the parameters impact on driving behavior, this paper improves a new mathematical model to calculate vehicle node speed, acceleration and security distance. In this way, the Mountain Highway VANETs Mobility Model(MHMM) is built.To study the coincident degree between Mountain Highway VANETs Mobile Model and the actual traffic flows, this paper uses Vanet Mobi Sim software to simulate the mobility model. The simulation results show that the vehicle nodes are aggregated at horizontal curve areas as well as its downstream, while dispersed at other areas. In addition, according to statistics and analysis of the trace files under different nodes numbers, we can see that the average speed variation and average space of vehicles both becomes smaller when the nodes are increasing. Those simulation results turn out that the MHMM has a high coincidence with the actual mountain traffic flows.Finally, the NS2 software is used to evaluate the protocol performances of Mountain Highway VANETs Mobile Model. As can be seen from the simulation results, the protocol performances under Mountain Highway VANETs Mobile Model are improved with the increasing number of nodes, while decreased with the increasing speed of nodes. When nodes are under the suitable distance, the protocol performances are better when the nodes are more uniform.The Mountain Highway VANETs Mobility Model in this paper can provide some reference data for the study of mountain VANETs. And then, we wish this model could improve the safety level in mountain highways.