Research On Interference Countermeasures For Active Blanket Jamming And Simulation System Verification

With the development of electronic countermeasure technology,active suppression jamming occupies an increasingly important position in radar electronic warfare.The radar jammer transmits high-power jamming signals to suppress the real target echo demanded by the radar side,which makes the radar in the radar side work ineffective.It has the characteristics of easy generation and large-scale radiation and is widely used in various occasions.The classic radar anti-jamming technology suppresses interference by means of pulse compression or sidelobe cancellation,but these methods do not have a good suppression effect on a variety of active suppression interference.Therefore,in order to combat different types of active suppression interference,it is necessary to Research the corresponding active suppression interference countermeasures.This thesis conducts research on countermeasures for coherent and non-coherent suppression interference.The main research contents are as follows:(1)Active suppression interference is classified into coherent suppression interference and non-coherent suppression interference.Noise convolution and noise product jamming are studied for coherent suppression jamming;scanning jamming,blocking jamming and sweeping jamming are studied for non-coherent suppressing jamming.The generation principle,time domain and power spectrum characteristics,and the behavior of radar receivers are studied for these interferences.(2)Aiming at coherent suppression of interference,interference suppression methods based on autocorrelation filtering and filtering in fractional Fourier transform domain are studied.The former uses the characteristics of the auto-correlation and crosscorrelation between the interference signal and the radar signal to filter the interference from the echo,and the pulse compression result shows a good suppression effect;the latter uses the acquired prior information of the radar transmit signal to The interference is filtered out from the Fr FT domain,and the beat preprocessing optimization is performed on the method,and a better effect is obtained in the case of a higher interference signal ratio,and the interference suppression method is analyzed.(3)Two different interference suppression methods are investigated for non-coherent suppression of interference.According to the interference characteristics,the interference suppression method based on interference reconstruction and cancellation is studied,and the interference is eliminated by estimating the interference mathematical model;the interference suppression method based on blind source separation is realized by using the technology of matrix joint diagonalization,and the ideal result is obtained.inhibitory effect.(4)The generation and suppression methods of active suppression interference signals are integrated,and the anti-active suppression interference simulation system is developed through the APP Designer platform in Matlab,and the functions of interference signal simulation,interference suppression realization,and suppression effect analysis are designed and verified.