Research On Collision Avoidance Schemes For PC5 Interface In LTE-V2X Networks

In recent years,the country’s economy and technology have developed rapidly,and vehicles have become the main means of transportation in people’s lives.With the increase of vehicles,traffic safety issues are increasingly prominent,the demand for realtime vehicle supervision and information interaction between vehicles has surged,and the Internet of Vehicle technology has emerged and developed rapidly.Wireless communication is one of the core technologies of the vehicle networks which owes highreliability and low-latency,and it is also an important foundation for realizing functions such as automatic driving.Internet of Vehicles based on cellular communication has achieved a dominant position in this field,and the Internet of Vehicles based on LTE(LTE-V2X)has been extensively researched and tested.The PC5 interface in LTE-V2 X networks can directly communicate between vehicles without a cellular network.However,there is no congestion control mechanism in the scheduling algorithm of the PC5 interface in the existing standard.When the vehicle is dense or the message frequency is high,the transmission load increases,which makes the channel busy and the collision rate increases,and in turn causes the information transmission failure rate to increase and the transmission delay increases.This will have a significant impact on the safety of the vehicle.The main work of this article includes:(1)In-depth study of the cause of the collision of the PC5 interface,analysis of the relationship between various variables and their impact on the packet delivery ratio,and design a congestion control strategy that Abandons the time and number of resource transmissions.Simulation results show that after using this scheme for congestion control,the collision rate decreases and the packet delivery ratio increases.(2)Based on the analysis of the PC5 interface scheduling process,for the situation where safety information needs to be transmitted in real time in the vehicle networks,the process of resource selection is advanced to predict the location of transmission resource occupation.An improved scheduling algorithm with only a small amount of sidelink control information is proposed and combined with the proposed congestion control strategy.Simulation results show that the hybrid scheme can further improve the packet delivery ratio.