高分五号可见短波红外高光谱影像在轨几何定标及精度验证

高分五号可见短波红外高光谱相机(AHSI)作为一颗具有高光谱分辨率的对地观测载荷,对复杂地物具有精确的探测与分类能力,高精度的几何定标对于卫星影像应用至关重要。本文采用了基于探元指向角的几何定标模型,分步解算内外定标参数,并选取多景影像进行实验验证。结果表明:通过严格的在轨几何定标,可见短波红外高光谱影像在无控制点的条件下,平面定位精度优于60 m (2个像素),内部精度优于0.5个像素,波段配准精度优于0.3个像素。

Geometric calibration for GF-5 AHSI camera

The advanced hyperspectral imager of GF-5 is a high spectral resolution camera, and it has outstanding recognition and classification ability for complex features and environments. The high accuracy geometric calibration is the key factor for the geometrical quality of satellite imagery. The geometric calibration model based on the pointing angle of the probe is used in this paper. The internal and external calibration parameters are solved step by step and some typical images are selected for experimental verification. The results indicated that the absolute positioning accuracy of AHSI can be stably better than 60 m (2 pixels) and the internal positioning accuracy is better than 0.5 pixels, the bands registration accuracy can be better than 0.3 pixels.