Study on Geometric Correction Algorithms for SAR Images

Geometric correction is an important step in the Synthetic Aperture Radar (SAR) image processing. A SAR image has to be geocoded before it is usable for further processing or information extraction. There are three major processes involved in a typical geometric correction: error modeling, ground control point selection and image transformation. In this paper, a study on four geometric correction methods namely global polynomial model, 2D direct linear transformation model, hybrid model and genetic algorithm with global polynomial model will be presented. By choosing appropriate ground control points, these geometric correction methods are applied onto an actual UAV SAR data for performance evaluation using root mean square error technique.