Recognition Of Deception Jamming Based On Correlation And Difference Of Doppler Frequency Shift In Multistatic Radar System

With the rapid development of electronic warfare and the emergence of digital radio frequency memory(DRFM),the deceptive jammer can generate deception jamming which is highly similar to the echo of the target.A monostatic radar system has limited interference detection and recognition capability.Multistatic radar system can form an omnidirectional and three-dimensional structure on the battlefield.It adopts technical measures such as information fusion and resource management to improve the ability of deception jamming detection and recognition.It has strong battlefield adaptability.Detection and recognition of deception jamming in multistatic radar system has become a research hotspot.In this thesis,the discrimination of deception jamming in multistatic radar system is carried out when target echo and deception jamming appear simultaneously in the radar tracking gate.The main work of this thesis is as follows:1.The research background and significance are introduced.The overview of multistatic radar system and the battlefield advantage over single radar system are described.The current research status of detection and recognition of deception jamming in multistatic radar system is summarized.The working principle of digital radio frequency memory(DRFM)is briefly introduced.The mathematical models of distance deception jamming,speed deception jamming and distance-speed joint deception jamming based on DRFM are presented in detail.The time domain and frequency domain characteristics are analyzed.Interference effect has also been analyzed.Then,the mechanism and principle of RGPO and VGPO are introduced.2.Aiming at the fact that the real target echo and the deceptive jamming co-exist in the radar tracking gate,the recognition algorithm of deception jamming in multistatic radar system based on correlation has been proposed.This method belongs to signal level fusion.In multistatic radar system,the real target echoes are independent of each other in different node radars under long-term baseline conditions,but the amplitudes of the jamming signals in different node radars are completely correlated because of the deception jamming generated from the same jammer.This difference is used to realize the recognition of deception jamming in multistatic radar system.Correlation measurement and parameter estimation are carried out on the amplitude sequence of the received signals by different nodes,and the test statistic is constructed to realize the recognition of deception jamming under the given false alarm probability.The effectiveness of the algorithm is verified by simulation experiments.3.Considering that the advanced jammer can mimic the amplitude fluctuation characteristics of real targets by digital technology,due to the different spatial position distribution of each noderadar in multistatic radar system,the radial velocity of true target is different from each other in different node radar,and the Doppler frequency shifts of the target measured by different node radars are not equal.Since the deception jamming received by different node radars is generated by the same jammer,the Doppler frequency shifts of the jamming measured by the radars are equal.Using this characteristic difference,the recognition of deception jamming in multistatic radar system is realized.Firstly,the echoes received by the radars are subjected to pulse Doppler processing,and the Doppler frequency shift information of the target is extracted.Then the Doppler frequency shifts are correlated to recognize the deception jamming.The algorithm belongs to the feature level fusion.The effectiveness of the algorithm is verified by simulation experiments.