红外与毫米波学报, 2018, 37 (5): 613, 网络出版: 2018-12-26
在轨超高分辨率傅里叶光谱仪仪器线型函数更新方法研究
Research on the method of updating instrument line shape function of on-orbit fourier ultrahigh resolution spectrometer
仪器线型函数 定标光谱 傅里叶光谱仪 太阳光谱模型 特征峰 在轨运行 instrument line shape function calibration spectrum fourier spectrometer solar spectrum model characteristic peak on-orbit
摘要
仪器线型函数是傅里叶光谱仪重要的物理表征参数之一, 影响仪器测量光谱的精度.随着空间测量和大气探测等遥感应用在高精度上的需求, 如何实时在轨测量并更新星载光谱仪的仪器线型函数, 成为当前提高在轨超高分辨率光谱仪测量精度的重要手段.以傅里叶型光谱仪为例, 根据仪器线型函数的原理, 利用在轨超高分辨率光谱仪实测太阳光谱定标数据不受大气气溶胶影响且具有独立太阳弗朗和费线的特征, 来对在轨超高分辨率光谱仪的仪器线型函数进行监督和更新.实验以Kurucz太阳光谱模型作为参考光谱, 在对应波段范围内分别选取多条实测太阳定标光谱和参考光谱的特征峰, 通过调整光谱仪的狭缝模型, 对特征峰残差进行迭代对比, 演算出仪器ILS参数变化.最后, 用更新的仪器线型函数与临边理论光谱卷积, 与实测临边定标光谱比较验证, 误差范围在-6%~8%.结果表明, 该方法可为在轨超高分辨率光谱仪仪器线型函数的监督更新提供参考依据.
Abstract
Instrument line shape function (ILS)is one of the important physical characterization parameters of the fourier spectrometer, which affects the accuracy of the spectrometer. With the high-precision demand for remote sensing applications such as space measurement and atmospheric detection, how to measure and update the ILS of the on-orbit spectrometer in real time is an important means to improve the accuracy of on-orbit ultrahigh resolution spectrometer. This paper used Fourier spectrometer as an example, according to the principle of ILS, used the characteristics of the measured solar spectral calibration data of the on-orbit ultrahigh resolution spectrometer, which have independent Fraunhfer line and less influenced by atmospheric aerosols, to monitor and update the ILS of the on-orbit ultrahigh resolution spectrometer. In this paper, the Kurucz solar spectrum model is used as the reference spectrum, the characteristic peaks of the measured solar calibration spectra and reference spectra are selected in the corresponding band, by adjusting the slit model of the spectrometer, the characteristic peak residuals are iteratively compared to calculate the ILS parameters of the instrument. Finally, after making a convolution between the updated ILS and the theoretical limb spectrum, we compared the results with the measured limb calibration spectrum. The error range is-6%~8%. These results show that this method can provide a reference for supervising and updating the ILS of on-orbit ultrahigh resolution spectrometer.
汪俊锋, 叶函函, 易维宁, 陈震霆, 方雪静, 杜丽丽. 在轨超高分辨率傅里叶光谱仪仪器线型函数更新方法研究[J]. 红外与毫米波学报, 2018, 37(5): 613. WANG Jun-Feng, YE Han-Han, YI Wei-Ning, CHEN Zhen-Ting, FANG Xue-Jing, DU Li-Li. Research on the method of updating instrument line shape function of on-orbit fourier ultrahigh resolution spectrometer[J]. Journal of Infrared and Millimeter Waves, 2018, 37(5): 613.