激光与光电子学进展, 2015, 52 (8): 083004, 网络出版: 2015-07-29
空间调制干涉成像光谱仪在轨相对定标新方法
A New Method of on-Orbit Relative Calibration for Spatially Modulated Imaging Fourier Transform Spectrometer
光谱学 光谱复原 在轨相对定标 相位匹配 相对定标系数 spectroscopy spectrum recovery on-orbit relative calibration phase matching relative calibration coefficient
摘要
干涉型成像光谱仪干涉数据会因探测器探元响应不一致产生畸变,而干涉图的极小偏差会导致复原光谱图有明显变化,所以对干涉图进行相对定标,消除探元响应不一致显得尤为重要.提出了一种基于辐射定标场的干涉型成像光谱仪在轨相对定标新方法,在没有实验室相对定标系数的前提下,只需要获取地面上垂轨方向覆盖数行CCD探元的均匀地物光谱,每一行地物光谱对应一帧干涉图,就可以通过这一均匀地物的光谱仿真出干涉图,与实际所测干涉图进行相位匹配后计算出相对定标系数.验证结果表明使用该方法对干涉图进行相对校正可以取得良好的效果,校正后的干涉图走势平稳,在远离零光程差处沿干涉方向呈现明显的干涉条纹,消除了复原光谱图中的条带.
Abstract
Interferograms of the spatially modulated imaging Fourier transform spectrometer can be distorted with the nonuniformity of array sensors,little deviation will result in notable variation in the recovered spectra,so it is very important to calibrate the interferogram and eliminate the nonuniformity of array sensors before recovery.A new method of on-orbit relative calibration for the spatially modulated imaging Fourier transform spectrometer based on radiometric calibration field is introduced without the calibration coefficient in laboratory,it only needs the spectra of a uniform field which covers several lines of CCDs across the orbit,each line of spectra corresponds to a frame of interferogram.Simulation and phase matching is carried out to calculate the calibration coefficient.The result shows that the method can get good performance.After calibration,interferogram has a steady tendency and shows significant streaks away from zero point,eliminating the strips in the recovered spectra.
常亚运, 易维宁, 杜丽丽, 乔延利. 空间调制干涉成像光谱仪在轨相对定标新方法[J]. 激光与光电子学进展, 2015, 52(8): 083004. Chang Yayun, Yi Weining, Du Lili, Qiao Yanli. A New Method of on-Orbit Relative Calibration for Spatially Modulated Imaging Fourier Transform Spectrometer[J]. Laser & Optoelectronics Progress, 2015, 52(8): 083004.