Research on the Method of Airborne SAR Direct Geocoding Based on Correction of Systematic Error

In this paper, a algorithm of airborne SAR Direct Geocoding based on correction of airborne SAR systematic error including slant range measurement error and time delay is put forward to improve the positioning precise, and POS/PPP technique is used to obtain radar phase center position data taking into account work efficiency. Many factors result in airborne SAR positioning accuracy, but main of them are slant range measurement error and time delay, if they couldn´t be corrected precisely, the positioning accuracy won´t be satisfactory. So this paper calculates the errors through some control points with P-band airborne SAR image of 2.5 meters resolution in mountain area of China (Xian, ShanXi), then we select eleven check points to make statistics. As a result, the horizontal accuracy is 12.6 meters, so the new algorithm on airborne SAR presented in this paper is efficient and practicable for airborne SAR Direct Geocoding in mountain area.