基于F-P标准具非线性波长校准的FBG传感系统解调方法

Demodulation method of FBG sensing system based on F-P standard with nonlinear wavelength calibration

针对光纤布拉格光栅(fiber Bragg grating,FBG)解调系统在变温环境下由于波长漂移引起的解调精度不足问题,提出了一种基于法布里-珀罗(Fabry-Perot,F-P)标准具非线性波长漂移校准的FBG传感系统解调方法。研究建立了引入F-P标准具的FBG解调系统,设计了基于F-P标准具非线性误差补偿的波长校准流程,搭建了FBG解调系统在航空航天实际应用环境中的模拟实验系统,并在恒温及变温环境下进行了实验测试。实验结果表明,本文所提出方法在恒温及变温环境下的传感系统解调稳定性在±0.6 pm及±1.1 pm以内,且在变温环境下传感系统解调的波长漂移量从20.3 pm减小到0.7 pm。验证了解调方法的精度和稳定性,为航空航天等领域的结构健康监测提供了参考。

Aiming at the problem of deficient demodulation precision in fiber Bragg grating(FBG)demodulation system caused by wavelength drift in a variable temperature environment,a grating method for FBG sensing system based on Fabry-Perot(F-P)standard for nonlinear wavelength drift calibration was proposed.In this paper,the FBG demodulation system based on the F-P standard is established,the wavelength calibration process based on the nonlinear error compensation of the F-P standard is designed,and the simulation experiment system of the FBG demodulation system in the practical application environment of aerospace is built,and the experimental tests are carried out in the constant temperature and variable temperature environment.The experimental results show that the demodulation stability of the sensor system is within±0.6 pm and±1.1 pm under constant temperature and variable temperature,and the wavelength drift of the sensor system demodulation decreases from 20.3 pm to 0.7 pm under variable temperature.The accuracy and stability of the method are verified,which provides a reference for structural health monitoring in aerospace and other fields.