Abstract: Mini snapshot high spectrometer can get images with two spatial dimensions and one spectral dimension at the same time, and the exterior orientation elements of the whole hyper spectral images instead of each frame, which can avoid geometric instability when scanning and can solve the large geometric deformation problem of push broom high spectrometer. So mini snapshot high spectrometer is suitable for small unmanned aerial vehicle platform. At present, the research mainly focus on radiometric correction of push broom high spectrometer. The application time of snapshot high spectrometer is relatively short, and the research on image processing is not adequate which has hampered wider use of this system. In this paper, the radiation response linearity and radiation response variability of mini snapshot high spectrometer load on UAV have been studied. At the same time, the correction method of radiation response variability has been studied, and the effectiveness of this method is assessed. The results show that before radiation response variability correction, there are the obvious vignetting effect and banding phenomenon on hyperspectral images, the radiation response variability coefficient after correction declines significantly, and the vignetting effect and banding phenomenon obviously decrease. The algorithm of multi-target radiometric calibration has been researched on, and the radiometric calibration accuracy is verified according to comparing the hyperspectral image spectrum calibrated with measured spectrum by ASD spectrometer. The results show that the radiometric calibration effect of multi target radiometric calibration algorithm is better, especially for near infrared band, the reflectance after calibrating is almost same as one measured by ASD spectrometer.

Key words: mini snapshot high spectrometer, push broom high spectrometer, radiation response linearity, radiation response variability, spectral calibration, radiometric calibration