Geometric ortho-rectification of flash radar images

The cartographic use of radar images and multisensor images fusion requires rectified images. The geometric errors of a radar image are induced by flight and system errors, as well as terrain elevation. The flash radar is a fast processing radar that acquires an image strip by strip, with a position dependent resolution. The ortho-rectification process must then deal with two different problems: correct each strip, and merge them. Due to the small number of available ground control points, and overlapping areas between strips, these two steps must be processed together. The paper presents two types of specific methods to correct flash radar images: interpolative methods, based on polynomial least square fitting, and parametric methods, based on nonlinear least square adjustment of a mathematical model of the flash radar geometric relations. A comparison is made between the first results obtained with these methods