Modified Orbit Algorithm with Sparse Ground Control Points for Geo-rectification of Space-borne SAR Image

A modified orbit algorithm with sparse ground control points(only three points)for high accuracy geo-rectification of space-borne SAR image is proposed,which is based onrange-doppler position model and high precision orbit data of GPS.The algorithm decreasesthe number of ground control points through simplifying the orbit parameter model,so it canimprove the work efficiency on the basic of high accuracy correction.