环境卫星HJlA超光谱成像仪在轨辐射定标及光谱响应函数敏感性分析

环境卫星HJIA搭载的超光谱成像仪HSI是我国第一个对地观测的星载高光谱传感器,针对超光谱成像仪缺乏各通道光谱响应函数这一问题,对传统的反射率基法予以改进,提出一种不使用光谱响应函数的场地定标方法.利用敦煌场地2009年8月定标实验数据,实现超光谱成像仪在轨辐射定标.通过构建不同形状的光谱响应函数,分析光谱响应函数形状对最终辐射定标结果产生的误差.结果表明,利用新提出的场地定标方法可以实现超光谱成像仪绝对辐射定标,除水汽和氧气吸收通道外,光谱响应函数对定标结果的影响小于3%,采用新定标方法得到的定标系数可以满足应用的需求.

HJ1A/HSI radiometric calibration and spectrum response function sensitivity analysis

Hyper spectrum imager (HSI) loaded on HJ-1A satellite is Chinese first spaceborne hyperspectrum sensor. Since the HSI has no spectrum response function of all channels, the usually used calibration method-reflectance based method has been modified, and a new calibration method is proposed, in which the spectrum response function is neglected. Based on the calibration experiment data of Dunhuang in Aug., 2009, the HSI sensor was calibrated on orbit. The different kinds of spectrum response were constructed based on the formula, and the errors of calibration results with different spectrum response function were analyzed. The results show, expecting for the channels of water vapor and oxygen absorption channel, the influence of spectrum response function in other channel is less than 3%, and the calibration result based on new calibration method can satisfy the application requirement.