Research On Inverse Synthetic Aperture Radar Imaging Methods And Jamming Methods

Inverse Synthetic Aperture Radar (ISAR), which can provide an all-time, all-weather, long-distance capability to generate a microwave imaging, is a high resolution microwave imaging system. ISAR, which has great prospects in both civilian and military applications, is an important research direction in radar imaging area. Electronic countermeasures has also become an indispensable technical means in modern warfare, therefore, ISAR imaging and jamming countering ISAR must be researched at the same time.This dissertation focuses on the imaging and jamming techniques of ISAR. The main conclusions of this dissertation are summarized as follows.1. Starting from the Walker Model, the processing of ISAR returned signal is analyzed. Then the effect of matched filtering in the returned signal processing is studied, and the linear frequency modulation signals (LFM), as well as the special treatment of their method-Solution Line FM processing (Dechirping) is researched.2. Based on the theory of ideal rotating platform and straight line motion ISAR imaging, the returned signal and the imaging principles of the complex motion target is studied. Then the Range-Doppler(R-D) imaging algorithm is expounded and the difficulty in the Range-Doppler (R-D) imaging algorithm, namely, motion compensation is researched here.3. The limitations of the R-D imaging algorithm are analyzed in the fourth part of the dissertation, namely, the scatterers can not walk more than one range cell within coherence time, or there would be Motion Through Resolution Cells (MTRC) phenomenon. From this polar format algorithm is brought up as a new imaging method. Through theoretical analysis and simulation verification, PFA can be a good correction of the phenomenon of MTRC, and the ISAR image quality will be greatly increased in case of large corner.4. The coherent jamming of the ISAR is studied in this dissertation, which focus on analyzing the effects of weighted noise frequency modulated jamming, weighted sawtooth frequency modulated jamming and frequency-shift jamming on ISAR returned signal, and detailed simulations are given here.In summary, this dissertation has achieved some helpful research results in ISAR imaging and jamming, and laid the foundation for the further research in these areas.