基于虚拟仪器技术的腔内吸收光谱波长调制与解调  

Wavelength Modulation and Demodulation of Intra-Cavity Absorption Spectroscopy Based on Virtual Instrument Technology

作　　者：韩文念[1] 汪曣[1] 刘琨[1] 贾大功[1] 刘铁根[1] 

机构地区：[1]天津大学精密仪器与光电子工程学院,天津300072

出　　处：《传感技术学报》2011年第10期1431-1434,共4页Chinese Journal of Sensors and Actuators

基　　金：国家973计划项目(2010CB327800);高等教育博士点基金项目(20090032110053)

摘　　要：在腔内吸收光谱研究中,采用波长调制技术以提高气体传感灵敏度。利用虚拟仪器技术,实现了光纤环腔激光器的波长扫描与调制;在建立谐波信号卷积模型的基础上,通过离散傅里叶变换的方法解调得到吸收信号的各阶谐波谱。采用此方法的测量系统结构简单,可有效地抑制部分激光噪声和干扰。实验结果表明,经调制解调测得乙炔气体在波长范围1 526nm～1 537 nm间的17条吸收谱线与光谱数据库一致,谱线精度只与波长调谐的精细度有关。In intra-cavity absorption spectroscopy studies,wavelength modulation technique is introduced to improve the sensitivity of gas sensors.Wavelength sweep and modulation of optical fiber ring laser are implemented using virtual instrument technology.After establishing the convolution model of harmonic signals,different order harmonic components of absorption lines are achieved by means of discrete Fourier transform.The measurement system with simple and easy operation can effectively reduce laser noise and interference.The experimental results showed that 17 absorption lines of acetylene measured through this method were consistent with those of HITRAN spectra database in the wavelength range from 1526 nm to 1537 nm,and the accuracy of spectra was only related to the fineness of wavelength tuning.

关 键 词：腔内吸收光谱 气体传感 波长调制 谐波谱 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置] TN253[自动化与计算机技术—控制科学与工程]