Interference Detection Analysis And Implementation Of GSM-R System

GSM-R(Global System Mobile for Railway),is developed as railway special digital wireless communication,dispatching and command system based on GSM system.It is also the wireless special system of the new generation railway,which undertakes the communication,dispatching and control of train and station,train and train,so its network reliability and safety is of special importance.However,for some reasons,its wireless frequency may be interfered by GSM system or other systems,resulting in great security risks.In order to detect and eliminate interference in time and to ensure the normal operation of the railway wireless communication dispatching system,it is necessary to analyze and detect the possible interference of the GSM-R system.In this paper,based on the study of the GSM-R system characteristics,through the analysis of system state in working environment,the modeling and simulation of the possibly existing independent frequency signal interference,broadband noise inteference,narrow-band network internal jamming in same frequency,narrow band GSM intermodulation interference have carried out,and the time domain and frequency domain characteristics of interference signals are analyzed.The method of communication interference detection has already had the algorithms of energy detection,time-frequency analysis,high order statistic analysis and circular stationary analysis.On the basis of simulation analysis of routine interference characteristics,this paper analyzes the interference detection algorithms,such as the CME algorithm,FCME algorithm and double-threshold algorithm,and the detection performance of these algorithms is verified by simulation.For two typical interferences of the GSM-R system,same frequency interference and intermodulation interference,this paper discussed a spectrum template correlation detection algorithm,through simulation,this method can analyze and identify the two types of interference.Based on the simulation of interference detection algorithm,this paper discusses the concrete implementation scheme of jamming detection system and simulates some algorithms on FPGA platform.Through the analysis of hardware simulation,the interference detection methods in this paper have high feasibility,good detection performance,and can be realized in real time with low cost.