Study On Distributed Cooperative Jamming Techniques Against Multichannel SAR

Due to the multiview observations of the scene,multi-channel SAR can realize height measurement via interferometry,ground moving target imaging,three dimensional imaging,jamming suppression and so on,which has improved the information sensing capability of SAR greatly and brought an austere challenge for SAR jamming.So,jamming techniques against multichannel SAR have already been hot research issue in SAR electronic countermeasure(ECM)area.Aimed to promote the anti-reconnaissance ability of the ground targets,and based on distributed cooperative jamming technique,this dissertation studies the new jamming techniques in the background of single-pass interferometric SAR(InSAR),multichannel SAR ground moving target indication(SAR-GMTI),and chirp rate polarity jittered SAR(CRPJ-SAR).Chapter 1 elaborates the background and necessity of this dissertation,briefly summarizes the development of SAR systems such as single-pass InSAR,multichannel SAR-GMTI and CRPJ-SAR,recalls the research status of SAR jamming technology,and lastly gives a brief introduction of the major works in this research.Chapter 2 studies the jamming techniques against single-pass InSAR.Firstly,based on the principle of InSAR imaging processing,the inteferometric phase and imaging characteristics of target with rotational micro-motion in single-pass InSAR are analyzed.Then,an active jamming method against InSAR based on micro-motion modulation is proposed,and the jamming effect is verified by simulation.Then,for the case that the SAR deceptive jamming implemented by single stationary jammer cannot generated three dimensional(3-D)deceptive scene in InSAR image and can be eliminated easily by dual-channel cancellation,a 3-D deceptive generation method based on dual-jammer cooperation is proposed;the 3-D deceptive jamming model is built,the relationship between the interferometric phase of jamming and the modulated complex scattering coefficient ratio of the two jammers is studied,and the control method of interferometric phase is presented.Finally,the effectiveness of the proposed method in generating 3-D deceptive scene and against dual-channel cancellation is demonstrated by simulation experiments.Chapter 3 studies the jamming techniques against multichannel SAR-GMTI.Based on the random change of key jamming parameters between each pulse,the complex intermittent sampling repeater jamming and random pulse separation and rearrangement repeater jamming against SAR-GMTI are developed,respectively,which can produce multiple barrage strips in both SAR and GMTI image,then the various jamming effects with different jamming parameters are also addressed.Based on three antenna clutter suppression and interferometry technique,the interferometric phase,estimated radial velocity and location of the deceptive moving target generated by single jammer in the multichannel SAR-GMTI are derived,which proves that the estimated azimuth location is always same with the jammer.Aiming at the limitation of the deceptive moving target generated by single jammer,a deceptive moving target generation method against multichannel SAR-GMTI based on dual-jammer cooperation is proposed,in which the interferometric phase of the deceptive moving target is dominated to satisfy the desired radial velocity via adjusting the complex scattering coefficient ratio of the two jammers,and finally simulations demonstrate that the method can generate deceptive moving target with controllable radial velocity and location.Chapter 4 studies the deceptive jamming techniques against CRPJ-SAR.The jamming effects of the intermittent sampling and sub-Nyquist sampling repeater jamming in CRPJ-SAR are analyzed,respectively;the modified time limited signal models of intermittent sampling and sub-Nyquist are presented,and the effectiveness of the intermittent sampling and sub-Nyquist sampling repeater jamming against CRPJ-SAR is verified by comparing the image results of repeater jammings in traditional SAR and CRPJ-SAR.A composite repeater jamming method against CRPJ-SAR via combining the scattering wave jamming with intermittent sampling or sub-Nyquist sampling repeater jamming is proposed,and the influences of sampling interval and duty ratio on the feature of the deceptive images are analyzed and verified by simulations,which show the composite repeater jamming can produce multiple distributed deceptive targets.Chapter 5 summarizes the main contributions and innovative work of this dissertation,and points out the future work.