Synthetic Aperture Radar Imaging And Self-focusing Algorithm

Synthetic aperture radar imaging algorithm and radar imaging autofocus algorithm are mainly discussed in this thesis.In the research on the SAR imaging algorithm, range Doppler algorithm and range migration algorithm are implemented. Range Doppler algorithms of multipoint targets could be adopted in the SAR imaging of the narrow and ultra-wide band signals respectively. The image shows that range Doppler algorithm could obtain high quality two-dimensional image in narrow band condition but worse quality in Ultra-wide band condition. For the Range Migration Algorithm, its two major steps, reference function multiplication and STOLT interpolation, have been mainly discussed. And the multipoint target imaging is simulated. Compared with the former R-D algorithm, R-D Migration algorithm has the superiority in processing of the Ultra-wide band signals.In the research on SAR imaging autofocus algorithm, the phase gradient autofocus algorithm is discussed firstly which achieves a better focusing effect using simulated data. According to problems of the traditional autofocus algorithms, the thesis introduces the Genetic Algorithm (GA) to SAR imaging autofocus and makes some improvements in accordance with the characteristics of the radar echo signal and imaging processing. Therefore, the Genetic Autofocus Algorithm is presented and has been applied to the SAR radar echo data with excellent imaging characteristics.