The Jamming Technique Against Waveform Agile SAR And Multi-channel SAR With The RCD Effects

Synthetic Aperture Radar(SAR) is an important part of information reconnaissance system, so jamming against SAR plays an important role of protecting information security. The theory and system implementation for jamming against SAR have made remarkable achievements for 20 years, and it greatly improves SAR anti-reconnaissance and anti-surveillance capability to protect information security in peacetime and wartime, in which the decoy jamming against SAR is the main development direction. However, the test has proved that the existing decoy jamming against SAR may defocus seriously in the wide scene imaging, and the conventional jamming may be restrained in waveform agile SAR or multi-channel SAR that makes a severe threat for information secrecy. We must study profoundly novel jamming technique against waveform agile(WA) SAR and multi-channel SAR. So this paper will study the improvement for the decoy jamming against scene wide SAR, and the novel theoretical analysis and engineering summary for jamming against the waveform agile SAR and multi-channel SAR/ WA-SAR.Chapter 1 describes the research background and significance of this research subject, which introduces the development history, present status and existing problems for SAR anti-jamming and jamming techniques, SAR system and SAR jamming evaluation techniques. And the novel anti-jamming and jamming of waveform agile SAR and multi-channel SAR techniques are especially analyzed. The major research efforts of this dissertation are also explained.Chapter 2 studies the effects of a number of anti-jamming technique for novel SAR and SAR jamming experimental phenomena. We firstly analysis signal characteristics and the algorithm for suppressing interference in waveform agile SAR(WA-SAR); then the algorithm for suppressing interference through STAP and the different phases statistical properties in military multi-channel SAR/ GMTI is studied to eliminate deceptive jamming based on Digital Radio Frequency Modulation(DRFM); So the new agile FJB signal is proposed and studied to develop the potential of multi-channel WA-SAR / GMTI. At the end, the imaging defocusing effect of conventional decoy jamming in the wide scene imaging by range curvature distinction is proposed from the conventional modulation techniques and testing of SAR jamming phenomena.Chapter 3 studies the novel decoy jamming against waveform agile SAR. The jamming strategies and principle against waveform agile SAR is elaborated. The theory of the variable intermittent sampling repeater jamming is proposed to adapt wide large signal in WA-SAR, which also solves isolation between transceiver and receivers as the intermittent sampling repeater jamming. Combined with regional confrontation characteristics, the variable intermittent sampling repeater jamming, the intermittent sampling scatter wave jamming and other intermittent sampling decoy modulation jamming in fast-time and slow-time domain is proposed and analyzed in waveform agile SAR. The jamming signal would made by repeating waveform agile SAR signal current pulses sections for electronic counter measure area information. And image characteristics of jamming agnaist waveform agile SAR are analyzed against the chirp rate agile SAR. The key jamming parameters are determined. As a clever jamming mode, the variable intermittent sampling repeater jamming, the intermittent sampling scatter wave jamming and other intermittent sampling decoy modulation jamming in fast-time and slow-time domain will provide a feasible and effective approach against waveform agile SAR.Chapter 4 studies the novel decoy jamming against multi-channel SAR/WA-SAR and GMTI. The jamming strategies and principle of multi-channel SAR/WA-SAR and GMTI is elaborated. The theory of the variable intermittent sampling scatter wave jamming and the intermittent sampling motion modulation scatter wave jamming are proposed and analyzed for waveform agile multi-channel SAR/GMTI, which can adapt wide large signal in WA-SAR and GMTI. Using the idea of variable intermittent sampling, moving jammer platforms or moving scatter targets as the core, the motion modulation is formed Doppler effects in multi-channel SAR, combined with the changing of delay time in fast time domain, or slow time phase modulation. The variable intermittent sampling scatter wave jamming and the intermittent sampling motion modulation scatter wave jamming is imaged in multi-channel waveform agile SAR/GMTI, which scatter wave jamming can produce multi-false moving targets against multi-channel SAR in the range and the azimuth domain. The characteristics of motion modulation jamming imaging and effects of reconnaissance errors on jamming images are also analyzed, which is proved by a typical scenario simulation experiment. It enriches the jamming motion modulation against multi-channel waveform agile SAR theory.Chapter 5 analyzes the imaging defocusing effects of conventional decoy jamming in the wide scene imaging by range curvature distinction. The conventional decoy jamming modulation technique is two-dimensional independent between fast-time and slow-time domain, and the coupling of them is neglected, which causes different range curvature distinction in the wide scene imaging between ground target echo and the jamming. The coherent image processing cumulative of jamming is firstly studied, then SAR image numerical model is established for range curvature distinction effects imaging by differenct range curvature distinction. And the SAR signal and jamming will also be studied and imaged between conventional R-D and CS algorithms in different range curvature distinction regions. And the improvement technique of conventional decoy jamming through compensating range curvature distinction may help improving decoy jamming modulation techniques, when the coupling of fast-time and slow-time domain can’t be neglected. So this study will improve the wide scene SAR deception jamming modulation technology and enrich large scenes interference modulation theory.Chapter 6 summarizes the research work for main innovations with discussing the futurer work to be researched.