Mini SAR影像的定向参数计算方法分析

首先分析对比了国产小型IMU/GPS组合导航获取的小POS数据特点，因仪器精度有限引起的测量误差无法在成像过程中消除，相位误差导致了Mini SAR影像中部分目标成像出现方位向散焦、模糊，导致目标像点坐标出现误差。将传统定向参数计算方法用于Mini SAR单幅影像定位时，地面控制点数量、像点坐标、定向参数误差向量的限差、地形特征、DEM分辨率及POS数据精度等因素都会影响定位结果。当对定位精度要求不高时，多项式插值POS数据获取的天线相位中心的空间位置、速度比拟合更准确。

Analysis of Directional Parameters Based on Mini SAR Image

In this paper,the author analyzes the characteristics of small POS data.The measurement error that caused by instrument accuracy can not be eliminated in the imaging process,the remaining phase error causes several targets appear azimuth defocusing and blur,which leads to the coordinate error of the image target point. The author applies the traditional directional parameter calculation method to Mini SAR single image locate,there will the number of ground control points,image coordinates,the tolerance of directional parameter error vector,terrain features,DEM resolution,the accuracy of POS data and other factors will affect the positioning results. When the high positioning accuracy is not necessary,polynomial interpolation of POS data results is more accurate than fitting.