Research On Vertical Handoff Algorithm In Internet Of Vehicle Environment

Heterogeneous Internet of Vehicle is the inevitable trend of the development of car network,which is the integration of a variety of wireless communication technologies in the automotive environment.Car users can increase the travel efficiency while connecting to the Internet anytime,anywhere to enjoy multimedia resources and on-board services.Network switching technology is the core issue in heterogeneous car networking,switching algorithms directly affects the quality of service terminal.Therefore,this paper selects two kinds of representative networks to carry out the research of vertical handover algorithm in heterogeneous Internet of Vehicle,namely LTE network and WIFI network.Aiming at the problem of unbalanced nodes in heterogeneous Internet of Vehicle,this paper improves a network selection method based on load balancing.This method mainly selects the most appropriate network for the initial car network to balance the network resources.This network channel utilization and improve network congestion control has a great role,but also can reduce the vehicle load caused by frequent network switch.Then,aiming at the speed of vehicle nodes moving in and out of different network coverage areas due to the fast speed of vehicle nodes in heterogeneous vehicle network,the ultimate success rate of handover is low,and the ping pong effect caused by this problem is introduced.In this paper,a vertical handoff algorithm based on motion trend prediction is proposed.In the heterogeneous vehicle composed of LTE,WIFI network environment,the first prediction of moving tendency in Manhattan using the model,and then calculate the current station coverage under the residence time,according to the time of the vehicle nodes are divided into long residence time and short residence time node.For the long residence time node,the switching decision is made based on the load balancing based network selection method.For the short residence time node,a multi-attribute vertical handoff algorithm based on fuzzy analytic hierarchy process is designed to perform the switching decision.In this algorithm,noise than different access networks(SINR),switching delay,communication overhead,the available bandwidth attributes as the factors influencing the handover decision,and according to the network properties of the alternative network to establish the attribute matrix,using fuzzy AHP to determine the weight of each attribute,and with the simple and weighted method to judge whether it is connected to the target network.From the simulation results,we can see that in the two simulation scenarios of different vehicle number and vehicle speed,the ping pong effect is reduced,the network delay is improved significantly,and the system throughput is improved.