Development of Two Practical R-D Location Model and Precision Comparison Between Them
星载ASR图像的两种实用比R—D定位模型及其精度比较

Synthetic Aperture Radar (SAR), as a kind of active remote sensors, is a system that can scan and image earth surface objects in a high resoution using its EM wave. Ever since the late of 1970s, SAR as a way of earth observation has progressed to the space borne stage. However, to utilize SAR image product adequately and efficiently, we often need to locate accurately an arbitrary pixel, which is corresponding with the target on the earth surface. Taking Radarsat 1 as an example, this paper first briefly describes the multi level, multi type traits as well as the product format of SAR image. After comparison of several location methods of remote sensing image, R D theory is proved to have its advantage as the footstone of absolute pixel location model of SAR image. In developing pixel location model, the dilemma of employing direct coordinates transformation is pointed out and two practical location algorithms based on R D theory are presented. The test results betrary that the relative position location algorithm can achieve a high accuracy no less than the similar research till to now in the world. The iteration location algorithm can also achieve a high accuracy permitted in the technical document of RSI Co. and therefore has a certain practicability.