Research On Multi-false-scenes Deception Jamming Based On Frequency Diverse Array

In recent years,the Electronic Counter Measure(ECM)technology against Synthetic Aperture Radar(SAR)has been growing more demanding with the rapid development of SAR in the military and civilian fields,which making SAR deception jamming technology gradually becomes the focus of domestic and foreign research scholars.The method of Digital Radio Frequency Memory(DRFM)to generate jamming signals becomes the current mainstream technology for the deceptive jamming against SAR because DRFM can reproduce the radar signal accurately and quickly.Considering the effect of deception jamming depends on the measurement accuracy of SAR parameters,and the repetitive convolution operation is required to generate multiple false scenes in the SAR imaging results,this thesis proposes space-time-doppler multi-dimensional joint deception jamming technologies against SAR based on the Frequency Diverse Array(FDA),a new system of antenna array.This thesis takes this as the background to carry out the research,and the main research contents are as follows:Firstly,a direct-path deception jamming against SAR using the FDA is proposed.Considering the effect of deception jamming depends on the measurement accuracy of SAR parameters,a geometric model of direct wave deception jamming based on the FDA is established,and instantaneous slant distance between the SAR platform and the predesigned false scene is obtained by the cooperative network of the jammer and receivers.Then the DRFM modulates the locally stored radar signal according to the template of false scene and the FDA transmits the jamming signal with different carrier frequencies of different elements,and finally obtain a finely modulated false scene.On this basis,the results of the deception jamming echo signal after being processed by the Range Doppler Algorithm(RDA)are derived in detail,and the optimal layouts of the receivers are obtained according to the condition number analysis of the far-near field SAR.Then,a scattered wave deception jamming against SAR using the FDA is proposed.this method changes the propagation path of the radar signal and utilizes the ground background to generate the deception jamming signal based on the geometric model of the scattered wave deception jamming using the FDA.Furthermore,there is no need to predesign the template of false scene and reduces the complexity of deception jamming against the SAR.Then the range and azimuth results of the deception jamming echo signal after RDA imaging processing,and the error introduced in the range,azimuth and azimuthal frequency modulation rate of the SAR are discussed and analyzed in great detail.Finally,the signal simulation data of the radar echo of point targets and the survey radar data of the RADARSAT-1 and GF-3 satellites are utilized to verify and analyze the effectiveness and correctness of the proposed jamming technologies.The results show that the deception jamming methods proposed in this thesis can produce multiple similar false scenes in the SAR imaging results,which has an excellent effect of deception jamming.