高分四号静止轨道卫星高精度在轨几何定标

High Accuracy On-orbit Geometric Calibration of Geostationary Satellite GF4

高分四号是世界上第一颗静止轨道高分辨率光学遥感卫星,高精度的几何定标是确保其成像几何质量的关键。本文分析了静止轨道卫星成像几何误差源及成像区域特点,提出了其严格几何成像模型;并在此基础上提出了静止轨道卫星面阵传感器在轨几何定标模型与定标参数估计方案。本文利用Landsat 8数字正射影像与GDEM2数字高程模型对高分四号卫星进行在轨几何定标,结果表明,通过严格的几何定标,可见光近红外传感器与中红外传感器的内部畸变在沿轨与垂轨方向上均稳定优于1个像素,通过统计分析可知,高分四号静止轨道卫星影像的绝对定位精度会受到成像时间与成像角度的影响而存在显著的波动。

GF4 satellite is the first high resolution optical geostationary satellite for remote sensing in the world, and the high accuracy geometric calibration is the key factor for the geometrical quality of satellite imagery. The positioning errors and the features of imaging region of GF4 were analyzed, the rigorous imaging model was introduced. Then on orbit calibration model and parameters estimation method were introduced for planar array sensor of GF4 satellite. The experiments used the DaM of Landsat 8 and DEM of GDEM2 for the on-orbit calibration, and the results indicated that internal accuracy of the panchromatic and near-infrared sensor and intermediate infrared sensor can be stably better than 1 pixel in the along and vertical track direction, and the absolute positioning accuracy of GF4 would be greatly affected by imaging time and imaging angle, and fluctuated remarkably.