基于少量控制点的Radarsat-2影像快速几何纠正技术研究

A Rapid Radarsat -2 Image Geometric Correction Technique Using a Few GCPs

Radarsat-2卫星依据其搭载的GPS接收机可实现3倍中误差小于60m的精确实时定轨。由此本文提出依据其影像元数据信息实现快速几何纠正的方法,该方法利用少量的几个控制点来消除Radarsat-2影像与待纠正参考系间的系统误差,从而实现Radarsat-2影像的快速几何纠正。本文并依据SAR斜距成像原理的纠正公式和实地采集的GPS数据,验证了元数据中所提供RPF模型的内部精度和外部符合精度。通过实验验证了本快速纠正技术可以获得中误差小于2个像素的平面几何纠正精度。

Taking advantage of its onboard GPS receiver, Radarsat-2 satellite can determine orbit in real-time with three times RMS less than 60 meters. A rapid geometric correction technique is proposed in this paper. The systematic error between Radarsat-2 images and the actu- al reference coordinates can be eliminated by imposing a few ground control points to the RPF coefficients extracted from SAR products. The inside accuracy of this method has been tested by the formulation which got by the principle of SAR imaging. The outside accuracy has been tested by field collected GPS data. This experiment proofs that this technology can achieve geometric con＇eetion accuracy with RMS less than 2 pixels.