机载干涉SAR产生的未经地理编码的DEM有较高的相对高程精度,但因其是基于斜距表达的,且干涉几何定标存在误差,需要利用控制点来进行绝对定向。本文首先改正由地形起伏引起的像点位移,将斜距DEM转换成地距DEM,然后根据空间相似变换,将地距DEM视为刚体,利用控制点求模型平移偏量、缩放因子及旋转角,达到绝对定向的目的。 Geocoded DEM generated by airborne interferometric SAR has higher relative elevation accuracy, but because it is based on slant range expression and there is an error in geometric interference calibration, it is necessary to use the control point for absolute orientation. In this paper, we first correct the pixel displacements caused by the topography and undulate, and then convert the slant range DEM into the ground distance DEM. Then according to the spatial similarity transformation, we consider the ground distance DEM as a rigid body, and use the control points to calculate the model offset, scaling factor and rotation angle , To achieve the purpose of absolute orientation.