基于天宫一号高光谱成像仪的替代光谱定标方法精度对比分析

基于天宫一号高光谱成像仪2012年3月6日获取的可见近红外谱段数据,分别进行了氧气吸收通道的同步和非同步替代光谱定标,为了提高非同步替代光谱定标结果的可靠性,利用与同步实验日期相近的另外两景图像进行了多次非同步替代光谱定标.结果表明:基于三景图像的非同步替代光谱定标结果相近,差异小于0.2 nm,标准差小于0.11;同步和非同步两种替代光谱定标结果差异小于0.3 nm;以星上定标结果为基准,两种替代光谱定标方法的误差分别为0.384 nm和0.489 nm,二者差异较小.可见,可采用非同步替代光谱定标方法对高光谱成像仪进行高频次的光谱定标.

A comparative analysis of the accuracy of alternative spectral calibration methods based on TG-1 hyperspectral imager

Based on the visible near-infrared (VNIR) data acquired by TG-1 hyperspectral imager on March 6, 2012, synchronous and non-synchronous alternative spectral calibration were assessed at the oxygen band. In order to improve the reliability of non-synchronous alternative spectral calibration result, other two images with similar imaging date were used to achieve multiple calibrations. The results show that non-synchronous alternative spectral calibration results based on three images are similar, difference is less than 0.2nm, and standard deviation is less than 0.11. Difference between synchronous and non-synchronous alternative spectral calibration results is less than 0.3nm. Compared with the TG-1 on-board spectral calibration results, the error of the two alternative spectral calibration methods is 0.384nm and 0.489nm, respectively. The accuracy difference is relatively small. Non-synchronous alternative spectral calibration method can be used to achieve high-frequency spectral calibration for hyperspectral imager.