基于TDLS的光谱吸收型CO2传感器仿真与实验研究

摘要

In this paper,a simulation model and experimental demonstration based on the TDLS ( tunable diode laser ab-sorbing spectrum) technique were conducted to analyze the relationships between gas concentration and harmonic of absorbed sig-nal for carbon dioxide detection.Investigation on the effect caused by modulation factor to harmonic intensity was considered in the simulation,and the parameters were optimized for detecting system.Through calibration measurement,relationships between gas concentration and harmonic intensity were analyzed.The test result was improved by signal averaging and integrating.A precision-enhanced result of carbon dioxide detection is achieved in this paper and this technique provides a route for effective analysis and design of applications of TDLS.%文中采用可调谐半导体激光器光谱吸收技术(TDLS),针对激光调制参数设置问题,建立CO2气体光谱吸收理论模型,分析光谱吸收后产生基波、二次谐波信号与气体浓度的关系.使用Simulink进行仿真,研究激光器调谐系数对谐波强度的影响,并优化了实验系统的设计参数.通过搭建CO2检测系统,进行气体浓度定标测试,得到气体浓度与谐波强度的关系,采用叠加平均和积分的方法处理检测信号,使系统性能得到显著提高.由此实现了CO2气体高精度检测,为谐波检测技术的实际应用提供了参考.