FTS干涉信号延时补偿算法的仿真分析  

Time-delay Compensation Simulation and Analysis of Interference Signal Based on FTS Technology

作　　者：翟茂林 李涛[1] 张玉贵[1] ZHAI Maolin;LI Tao;ZHANG Yugui(Beijing Institute of Space Mechanics & Electricity, Beijing 100094, China;Beijing Engineering Technology Research Center of Aerial Intelligent Remote Sensing Equipments, Beijing 100094, China)

机构地区：[1]北京空间机电研究所,北京100094 [2]北京市航空智能遥感装备工程技术研究中心,北京100094

出　　处：《航天返回与遥感》2019年第3期47-56,共10页Spacecraft Recovery & Remote Sensing

基　　金：地球观测与导航专项;国家重点研发计划项目:大气辐射超光谱探测技术(2016YFB0500700)

摘　　要：基于干涉分光原理的傅里叶变换光谱仪通过将激光信号作为采样参考信号对干涉信号进行等光程差采样,然而动镜扫描不稳以及后续焦平面电路的差异会造成干涉信号与激光参考信号之间存在相对延时,导致数据的非同步性。随着多元探测器技术的快速发展,探测器信号路数急速扩展,目前广泛采用添加延时线的延时补偿方法需要大量硬件配置将不再适用。文章针对该问题提出一种延时补偿的软件实现方法,利用通过建模仿真得到的干涉数据完善了激光信号过零点获取、干涉数据重构等算法,并通过MATLAB进行了补偿原理的仿真分析。结果表明:通过该算法对干涉信号进行延时匹配重采样,可以将相对延时补偿到1μs以内,光谱复原度高于99%,可较好抑制动镜扫描不稳带来的光程差采样误差。用于高光谱遥感的后期数据处理,可有效提高光谱复原精度。As to Fourier Transform Spectrometer based on the Michelson Interferometer, a laser interference signal is provided as the reference signal to sample the interference signals with identical optical path difference. Both the dynamic instability of the scanning mirror and the difference of focal plane circuits will result in the relative time delay between the laser interference signal and the interference signal, causing non-synchronicity between the two signals. Currently, with the sharply increasing of the number of pixels on the focal plane, the signal links are such a large number that adding delay line is no longer applicable as a result of too much workload for hardware configuration. In this paper, a kind of software method for compensating the relative time delay is proposed to substitute the hardware method of adding delay line, and the principle of compensation is simulated and analyzed with MATLAB. The result shows that the relative time delay can be compensated to 1μs and the spectral recovery accuracy is higher than 99% by matching the time delay and resampling the interference signal. The sampling error of optical path difference caused by the unstable scanning speed of the moving mirror can be effectively suppressed. This method can be used in data processing of hyperspectral remote sensing and effectively improves the precision of spectral restoration.

关 键 词：傅里叶变换光谱仪 延时补偿 干涉图重构 高光谱遥感 

分 类 号：TP732.2[自动化与计算机技术—检测技术与自动化装置]