Improved Image Reconstruction from Sub-apertures of Circular Spotlight SAR

摘要

Reconstructing images from SAR returns is usually a time consuming task. In addition it is often desired to use as many returns as possible to achieve better image quality. However, the high computational resources demand by the conventional methods hinders the reconstruction process. In this article, we propose a simple method to reconstruct SAR image that is built upon the back-projection algorithm using multiple sub-aperture imagery to attain both greater processing efficiency and improved image quality. Instead of aggregating all the available pulses into one single image following the back-projection algorithm, our proposed method creates multiple SAR image reconstructions from a relatively small number of pulses to exploit variations in sub-aperture views of the scene. The heterogeneity among these sub-aperture views exhibits an exceptional difference between various objects and presents a reconstruction with much less noise. Our proposed method is evaluated with circular spotlight GOTCHA data sets and it demonstrates much improved computational performance and image quality compared to the conventional back-projection algorithm.