Research On Radar Deception Jamming Identification And Suppression Technology In Time-frequency Domain

As an all-weather information sensing equipment in modern warfare,radar has become the core equipment for battlefield reconnaissance and monitoring,target orientation,and weapon guidance,and has been widely used in many fields such as the military and civilians.At the same time,radar is facing various electronic countermeasures(ECM)threats,especially with the development of digital radio frequency memory(DRFM)technology,the radar active deception jamming based on DRFM can not only enter the radar system from the main lobe of the antenna but also has the characteristics of low power and high similarity with the real echo,which poses a great threat to the normal play of radar detection ability.To reduce the threat of active deception jamming,especially the jamming from the main lobe into the radar system.This article has thoroughly studied the basic principles and characteristics of common deception jamming based on DRFM,combined with image processing technology,and researched the recognition and suppression of radar active deception jamming from the timefrequency domain.The main contents are as follows:1.Aiming at the situation of spoofing interference and echo separation in the time-frequency domain,and anti-spoofing interference technology based on image segmentation is proposed.First,perform the time-frequency transformation on the received radar echo signal to obtain a mixed-signal time-frequency diagram,and perform gray-scale processing on the time-frequency diagram to convert RGB three-dimensional data information into one-dimensional information;secondly,use global threshold and Mask R-CNN performs segmentation processing on the signals in the original timefrequency image to obtain the time-frequency image of each signal;then,extract the color component features of the segmented image,and use deep random forest(DRF)for interference recognition;finally,based on the recognition The result and the position information of the real signal are designed to design a two-dimensional time-frequency filter to filter out interference and noise.The algorithm has low complexity,which does not need to estimate the signal parameters.Experimental results show that the algorithm can achieve an interference recognition rate of more than 90% when the jamming signal rate(JSR)is greater than 3d B and less than-2d B,and the interference suppression when the signal-to-noise ratio(SNR)is greater than 10 d B The correlation coefficient between the latter signal and the real echo signal reaches more than 94%.2.Aiming at the overlap of interference and echo in the time-frequency domain,such as dense false target interference,an anti-spoofing interference technology based on blind source separation is proposed.First,perform the time-frequency transformation on the received radar echo signal to obtain a mixed-signal time-frequency diagram,and perform dimensionality reduction processing.At the same time,to reduce time complexity and ensure that the output is solvable,the dimensionality reduction data is centralized and whitened;secondly,Use the independent component analysis algorithm of the dream particle swarm to solve the separation matrix,and use the separation matrix to separate the input;finally,perform interference recognition based on the separated signal,retain the true echo signal of the target based on the interference recognition result,and discard the interference signal to achieve Interference suppression.Experimental results show that when the SNR is greater than 10 d B,the correlation coefficient between the separated signal and the real echo signal reaches more than 90%,and when the SNR is greater than 4d B,the interference recognition rate reaches more than 90%.