Infl uence of geometric distortion on SAR Image matching and its correction
几何失真对SAR图像匹配的影响及校正方法分析

The accuracy of scene matching navigation system can be improved greatly when synthetic aperture radar (SAR) is used. However, geometric distortions of SAR real-time image, which are caused by terrain undulation and atmosphere turbulence etc, decrease the matching performance. By analyzing the causations of geometric distortion, a two-dimension separable correction method is presented, which corrects the distortion in azimuth direction by phase compensation along with the imaging processing, and leaves the distortion in range direction to the image post processing. In the end, an experiment was conducted based on three SAR real-time images of different terrains. Each of the images is simulated by digital elevation model (DEM) and orthography, and then corrected by three different methods. Based on the experimental results, some rules of the correction method selection are acquired.