High-resolution Airborne Sar Imaging Study

Synthetic Aperture Radar (SAR) is a well-known remote sensing technique. With the rapid development of modern science and technology, higher resolution images from the airborne SAR are required. On the basis of the theory of high-resolution SAR imaging, this dissertation introduces the SAR imaging model. Then in Chapter 3, two imaging algorithms, Range-Doppler Algorithm and Chirp Scaling Algorithm, which suit high-resolution side-looking SAR (including slightly squint SAR) imaging, are discussed, simulated, and their imaging quality indexes and performance are prepared.Because of the phase errors caused by aircraft's motion errors, accurate motion compensation should be applied to get high resolution, high contrast and low geometric distortion SAR images. In Chapter 4, bad effect of different types of motion errors on SAR imaging is firstly discussed, and the main types of phase errors are simulated. Then a compensation method directly extracting phase errors from raw data is discussed. This dissertation discusses a robust autofocus algorithm: Phase Gradient Autofocus Algorithm, and its application in Stripmap Mode SAR. Both the imaging algorithm and autofocus algorithm are basically applied in practice, and desired outcome is obtained.In a word, this dissertation doesn't only introduce the two important aspects of high-resolution airborne SAR: imaging algorithm and autofocus algorithm, but also applies them in computer simulation and practice, and proves their validity.