双光栅匹配解调系统线性解调模型的研究  

Investigation on linear demodulation model of two matched grating demodulation system

作　　者：詹亚歌[1] 裴金成[2] 杨熙春[2] 向世清[2] 

机构地区：[1]东华大学应用物理系,上海201620 [2]中国科学院上海光学精密机械研究所,上海201800

出　　处：《仪器仪表学报》2008年第12期2611-2616,共6页Chinese Journal of Scientific Instrument

摘　　要：对双光栅匹配波长解调法进行深入研究,得到一种线性解调的理论模型并进行了实验验证。理论和实验研究表明,若两个解调光栅的带宽相等,则两个探测器输出电压之比的对数与被测传感光栅的中心波长成严格的线性关系;测试过程中的附加偏置电压对解调系统的性能有严重影响,系统的解调精度、灵敏度和线性范围均随偏置电压的增大而逐渐减小。另外,在此线性解调理论的基础上,提出了可调谐双光栅解调法,该方法不仅可以扩大原有系统的解调范围,而且能够用于多个光纤光栅中心波长的解调。Through deep investigation on two parallel matched grating interrogating technique, a linear demodulation theory model was designed and experimentally verified. The linear formula between the logarithm of the output voltage ratio and centre wavelength of the sensing fiber Bragg grating（FBG） was obtained under the condition that the bandwidths of two interrogation FBGs correspond to same value. Investigation show that, the exerted voltage offset has serious influence on the performance of the system, and the precision, sensitivity and interrogating range of the system decrease with the increasing of the exerted voltage offset. In addition, a tuneable two matched grating demodulation system is proposed, it not only can extend the interrogating range of the former system but also can be used to demodulate several wavelengths of grating sensor network simultaneously.

关 键 词：光纤光栅传感器 解调技术 线性范围 灵敏度 

分 类 号：TP212.14[自动化与计算机技术—检测技术与自动化装置]