WANG Yan-ju ~. Design on faint signal processing circuit for difference absorption gas sensor[J]. 2006, (6): 13-15. DOI: 10.13873/j.1000-97872006.06.004.
用于气体差分检测的微弱信号处理电路的研究
摘要
为了提高气体差分传感系统的信噪比
基于微弱信号的相关检测原理
设计了以锁相放大器为核心的微弱信号处理电路。实验表明:电路输出电压与检测气体体积分数呈线性关系
电路对气体体积分数的检测极限为150×10-6
检测系统对检测气体体积分数的误差为1%
具有较好的重复性及选择性。
Abstract
In order to improve signal to noise ratio(SNR) of the differential absorption gas sensor system
based on the correlation detection principle
a faint signal processing circuit is designed centering around lock-in amplifier.Experimental results indicate that the output voltage of detective circuit is linear with the gas volume fraction
the limit value is 150×10
-6
.The error of the whole detection system to the gas volume fraction is 1 %
the repeatability and selectivity of the system is better.