气体滤波相关技术在红外甲烷监测系统中的应用  

Application of Gas Filter Correlation Technique in IR Monitoring System of Methane

作　　者：陈晓宁[1,2] 刘建国[1,2] 司福祺[1,2] 刘文清[1,2] 

机构地区：[1]中国科学院安徽光学精密机械研究所中国科学院环境光学与技术重点实验室,合肥230031 [2]安徽省环境光学重点实验室,合肥230031

出　　处：《光电工程》2008年第4期49-52,共4页Opto-Electronic Engineering

基　　金：国家高技术研究发展基金资助项目(2002AA641020)

摘　　要：针对空气痕量气体中甲烷含量低、吸收弱,在非分散红外甲烷检测系统中噪声干扰大的问题,本文提出了利用气体滤波相关检测技术去除背境噪声干扰来提高检测能力的方法。该方法依据气体对红外辐射的特征吸收和相关运算的原理,结合了先进的气体滤波技术和相关检测技术,实现了对微弱光谱信号的调制和检测,最后实现了对浓度的反演,从而达到了甲烷气体实时、快速在线检测目的。试验结果表明,系统有10ppb的测量精度。A novel method of Non-dispersion Infrared （NDIR） based on correlative technology for measuring CH4 trace gas and its application in the field measurement are described in the paper. Because of low concentration and weak absorption, atmosphere methane detection with Non-dispersion Infrared （NDIR） system faces the problem of high noise interference. To improve detection ability, Gas Filter Correlation （GFC） technique is put forward to reduce background noise. Correlative technology plays an important role in detection of feeble signal. The method is based on the gas characteristic absorption in infrared region and the correlation operation principle. Feeble spectrum signal is modulated and detected by combining advanced Gas Filter Correlation （GFC） technique and correlation technique. Methane is detected in real time and fast. Experiment results show that the system detection precision can reach 10ppb.

关 键 词：气体相关滤波 弱信号 甲烷 

分 类 号：X831[环境科学与工程—环境工程]