HyMap-C机载高光谱仪定标方法与结果评价

Calibration method and results evaluation of HyMap-C airborne hyper-spectrometer

HyMap-C机载高光谱仪能够在400~2 500 nm波长范围内获取144个精细光谱通道,对于地球表面地物特征有极强的探测能力。为保证高光谱遥感数据的可靠性与定量化分析的精度,作者分别采用单色准直光法、漫反射板定标法和内部参考标准法对HyMap-C机载高光谱仪进行了实验室光谱定标、绝对辐射定标以及飞行过程中航线上相对辐射定标。通过航空飞行测量与地面实际测量的光谱反射率数据进行对比验证,结果表明两者整体谱型与局部吸收特征非常一致,定标结果可靠,数据可信。文中阐述的定标原理与方法为我国自主研制机载高光谱仪的定标提供了依据与思路,定标后获取到的高光谱分辨率数据可广泛应用于地质调查领域特别是矿物填图中。

The HyMap-C airborne hyper-spectrometer is capable of obtaining 144 fine spectral channels in the 400 - 2 500 nm wavelength range and has a strong ability to detect the features on the Earth＇s surface. In order to ensure the reliability of hyperspectrai remote sensing data and the accuracy of quantitative analysis, the authors used the monochromatic collimation method, the diffuse reflector calibration method and the internal reference standard method to carry out the laboratory spectral calibration, absolute radiometric calibration, and relative radiation calibration during flight of the HyMap-C. The comparison of spectral reflectance data between aerial measurement and actual ground measurement shows that both the local and global absorption characteristics of the two spectral curves have strong consistency, and the calibration results and the data are reliable. The calibration principle and method proposed in this paper provide the basis and idea for the calibration of the self- developed airborne hyper-spectrometer in China. The high spectral resolution data obtained after calibration can be widely used in the field of geological survey, especially in mineral mapping.