提高基于TDLAS的废气动态浓度测量系统分辨率与灵敏度的方法  

Improving Measurement System's Sensitivity of Gas Dynamic Concentrations Based on TDLAS

作　　者：肖兵[1] 梁瑛琳[1] 叶一如[1] 薛琦[1] 

机构地区：[1]华南理工大学自动化科学与工程学院,广东广州510641

出　　处：《仪表技术与传感器》2009年第5期99-102,共4页Instrument Technique and Sensor

基　　金：国家自然科学基金(60474042);广东省自然科学基金(04020000)

摘　　要：基于自平衡激光接收器和数字锁定放大器构造了TDLAS汽车尾气动态浓度测量系统。其中,自平衡激光接收器通过引入一个低频反馈回路去维持吸收信号和参考信号的自动平衡,有效地消除了背景噪音,扩大了测量范围;而数字锁定放大器采用一块DSP芯片TMS320F2812来实现相关检测算法,大大降低了系统的白噪音,提高了测量灵敏度。A measurement system for gas dynamic concentrations based on TDLAS was constructed by using an auto-balanced photoreceiver and a digital lock-in amplifier. The photo-receiver was able to reduce the background noise and increase measurement range by using a low frequency feedback loop to maintain automatic DC balance between signal and reference arms. The digital lock-in amplifier can cancel system white noise and get higher sensitivity by using a DSP chip of TMS320F2812 to carry out the correlative detection algorithm.

关 键 词：微弱信号 自平衡激光接收器 数字锁定放大器 

分 类 号：TP247[自动化与计算机技术—检测技术与自动化装置]