傅变光谱仪数据处理中相位误差非线性的分析及对Mertz相位修正方法的讨论  

Analysis of the Phase Error Non-Linearity of FTS and Discussion about Mertz Method

作　　者：刘岳[1] 赵永超[1] 耿修瑞[1] 唐海蓉[1] 丁赤飚[1] 

机构地区：[1]中国科学院电子学研究所,北京100080

出　　处：《光谱学与光谱分析》2009年第7期1809-1812,共4页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(40501041;40202031);"973"计划项目(2006CB403507;2007CB714401;2007CB714406);高性能地基高空间分辨率高光谱成像装置项目资助

摘　　要：傅里叶变换成像光谱仪在遥感应用中是一种很重要的科学仪器,在傅里叶变换光谱仪信号处理中存在相位误差的问题,文章阐述了相位误差产生的原因,分析了由零点采样偏移带来的相位误差的非线性,说明了产生这种非线性的原因是干涉图为有限长的离散序列,从一个新的角度通过数学推导的结果给出了这种非线性的解释和表达。接着由相位误差的非线性讨论了Mertz相位修正方法中的相位插值可能存在的误差,分析了已有的研究中的较好的处理方法,并提出了一种改进这种误差的补零变换的方法。使用通过标准光谱库中的源光谱数据仿真的干涉数据,对方法进行了比较和验证,说明了补零变换法可以改善相位插值的误差以及在一些情况下的相位突变,得到质量更好的复原光谱。Fourier transform spectrometer is an important instrument in the remote sensing applications. There are phase error problems in the Fourier transform spectrometer signal processing procedure. In the present paper, the Cause of phase error of Fourier transform spectrometers is shown firstly. It is mainly because of inaccuracy of sampling. Then the nonlinearity of phase error is analyzed. It is suggested that it is because that the interferogram is of finite length and the interferogram is discrete that this nonlinearity exists. The authors studied this problem with a new method. The nonlinearity is shown by rigorous derivation and the authors draw the conclusion by reasoning. Then through the nonlinearity of phase error, the authors have a discussion on the possible error in the Mertz phase correcting method. The possible error lies in the phase interpolation procedure, a part of Mertz method. A method consisting of zero adding and transforming is given to reduce this error. The methods are compared and illustrated by an experiment which uses simulated interferograrn from standard spectrum library. The experiment demonstrates that the method of zero adding and transforming can reduce the phase error of phase interpolation and improve the problem of rapid phase change under some circumstances, which can help get better spectrum.

关 键 词：傅里叶变换光谱仪 相位误差 非线性 Mertz修正法 

分 类 号：O657.3[理学—分析化学]