Research On Interference Detection And Identification Technology Of Beidou Civil Signal

Beidou Navigation Satellite Syetem(BDS)is independently developed and constructed by China.It is the third mature satellite navigation system after US GPS and Russian GLONASS.It is now widely used in various important fields in China.However,the unpredictable electromagnetic environment and the shortcomings of the navigation signal itself threaten the reliability of Beidou civilian signals.Therefore,BDS interference monitoring technology is the research focus of Beidou satellite navigation workers.In this paper,based on the analysis of BDS interference signals,the research of Beidou civilian signal interference detection and recognition technology and interference direction estimation is gradually carried out.The main work contents are as follows:First,the characteristics of the Beidou B1 I signal are described.The signal generation and spectrum analysis of single-tone interference,multi-tone interference,pulse interference,frequency sweep interference,and some noise interference are completed.The frequency domain,modulation domain and The impact of related domains.Second,it describes the continuous mean elimination(CME)algorithm,the forward continuous mean elimination(FCME)algorithm and the dual threshold FCME algorithm,simulates and verifies the performance of the algorithm,combines the characteristics of the Beidou civilian signal to improve the interference detection algorithm,builds the system and uses the measured data Confirm the accuracy and efficiency of the algorithm.Third,for several common interferences,extract interference feature factors such as frequency domain kurtosis coefficient,audio interference coefficient,frequency domain R parameter,and time domain kurtosis coefficient,complete threshold training,and design an interference recognizer based on decision tree theory,and Perform simulation analysis of recognition performance.Fourth,first study the principle of interference direction finding based on the MUSIC algorithm in the array antenna,and complete the direction finding simulation analysis.Second,study the principle of single antenna direction finding,introduce the specific process of using high gain antenna direction finding in this subject,and finally record the experimental data And complete interference to estimate.