中文摘要：

基于气体分子的近红外光谱吸收机理,研究一种可以检测一氧化碳的光纤气体传感器。对窄带光源DFB LD进行正弦波调制,建立差分吸收的数学模型,利用谐波技术实现气体浓度的检测。系统采用差分结构有效消除了光源光强噪声干扰以及光电器件的零点漂移。实验结果表明,传感器性能稳定、灵敏度高、重复性好,并且不受其它气体的干扰。

英文摘要：

Based on the near infrared spectral absorption of gases,an optical fiber gas sensor for the carbon monoxide concentration monitoring was described.Load the DFB LD with sinusoidal wave,established a mathematical model of differential absorption,and useed harmonic technology for the detection of gas concentrations.By using differential construction,it can eliminate the influence of interfering signals caused by the wave of LD＇s light intension,and zero shift of photoelectric device.The experimental results indicate that the sensor has a steady performance,high sensitivity and good repeatability,and it does not suffer from other gases interferences.