一种光纤Bragg光栅传感器解调系统的实验研究

Experimental Research for a Interrogating system of Fiber Bragg Grating Sensor

实验研究了基于可调谐光纤激光扫描的光纤Bragg光栅(FBG)传感器解调技术。系统由可调谐光纤F-P(TFFP)滤波器、掺Er光纤放大器(EDFA)、隔离器和耦合器组成可调谐激光光源,根据光电探测器输出波形、驱动电压与应变间关系实现了应变解调。分析了影响系统解调精度的原因,并做了相应的改进。实验测得,应变与TFFP驱动电压间的线性度达到0.998,且能达到1.26μstrain的高应变分辨率。

A fiber Bragg grating （FBG） sensor interrogation technology is studied based on the tunable fiber laser experimentally. In the system, the tunable laser is composed of a tunable fiber F-P （TFFP） filter,an embedded erbium fiber amplifier （EDFA） ,two isolators and a coupler. By finding the driven voltage corresponded to the peak value of photoelectric detector and the relation of driven voltage and strain,the strain information is well demodulated. Also the reasons affecting the precision of the system are analyzed and the relevant methods are employed to improve the precision. From the experiment results, the correlative linearity of strain and driven voltage of TFFP is 0o 998 ,and a resolution of 1.26 μstrain is obtained.