Research On Spectrum Allocation And Interference Coexistenc In 5G Celluar Vehicular Communication Systems

Cellular vehicular communication technology is an important part of the fifth-generation mobile communication system.Now researches on cellular vehicular communication systems have been conducted and one of the important researches is to find and how to divide new frequency bands for cellular vehicular communication systems to deployment.While the mutual interference between cellular vehicular communication systems and the wireless local area network(WLAN),the fixed satellite service(FSS)system,the radio positioning service system,which are deployed around the candidate band of 5.9 GHz,will result in the failed deployment of cellular vehicular communication systems.Therefore,researches on coexistence problems of cellular vehicular communication systems and other systems are necessary and needs to be conducted,which are of great significance for accelerating the spectrum allocation and operational deployment of cellular vehicular communication systems.This paper studies the vehicle-to-vehicle communication application in cellular vehicular communication systems based on long term evolution(LTE-V2X).Deterministic analysis and system-level simulation are used to analysis the mutual interference between V2X and WLAN,FSS and radio positioning service systems,then the coexistence suggestions are given.The main work and innovations of the thesis include:1?A coexisting system-level simulation platform of V2X,which is based on the Monte Carlo idea,is built by adopting modular design and object-oriented C++programming language.For the coexistence problem of V2X and WLAN,the coexistence analysis model is built.Then,the deterministic analysis method is used to analyze two scenarios of WLAN interferes with V2X and V2X interferes with WLAN,and the system simulations show the system performances under different vehicle speeds and different protection bandwidths.Finally,the results show that,the protection bandwidth isolation measure should be taken and the isolation bandwidth is more than 10MHz when V2X coexists with WLAN.2?In view of the coexistence problem of V2X and FSS,the coexistence analysis model is built.Then,the deterministic analysis method is adopted to analyze two scenarios of FSS earth station interferes with V2X and V2X interferes with FSS space station.And based on the coexisting system-level simulation platform of V2X,the system performances under different elevation angles of FSS earth station,different protection distances and different vehicle speeds are given.Finally,the results show that,the distance isolation measure should be taken and the isolation distance is more than 900m between FSS earth station and V2X.Besides,the protection bandwidth isolation measures need to be taken between FSS space station and the V2X.3?Aiming at the coexistence problem of V2X and radio positioning service system,the coexistence analysis model is built.Then,the mutual interference of the two systems are analyzed by the deterministic analysis method,and based on the coexisting system-level simulation platform of V2X,the system performances under different deployment modes and the different propagation models are presented.Finally,the results show that,the radar 4 and V2X should be deployed in adjacent frequency bands,and the radar 5 and V2X should be deployed in same frequency bands.Besides,the isolation distance between the radars and V2X is more than 1km.The research of this paper provides the interference avoidance measures and deployment suggestions for the coexistence of V2X with WLAN,FSS and radio positioning service systems when the 5.9GHz frequency band is used for V2X to deploy,which is of great importance to the spectrum planning and operation deployment of celluar vehicular communication system in China.