光纤法珀声发射传感器的双波长优化稳定方法

Optimum Double Wavelength Stabilization Method for Optical-fiber Fabry-Perot Acoustic Emission Sensors

提出一种采用优化设计方法改进的双波长稳定方法，能解决光纤法珀声发射传感器输出信号衰减与失真问题。分析双波长稳定原理并建立稳定优化模型。设计光纤法珀声发射传感器的双波长稳定方案，采用1×2密集波分复用器产生两路处于正交状态的输出信号，波分复用器滤波波长用优化模型求解。试验结果表明这种稳定方法具有无源与精度高的优点，当法珀腔长度变化范围为0～2μm，双波长最大正交误差为11％，能满足光纤法珀声发射传感器工作点的稳定要求。

A novel method for the fiber-optic Fabry-Perot acoustic emission sensors based on the optimum double wavelength stabilization technique is put forward, which can overcome an intrinsic disadvantage of fiber-optic Fabry-Perot acoustic emission sensors： signal attenuation and distortion. The double wavelength stabilization scheme for the optical fiber Fabry-Perot acoustic emission sensor is designed. An optical passive device, dense wavelength division multiplexer（DWDM）, is used to generate two quadrature phase-shifted output signals. The filtering wavelength of DWDM is calculated by the optimization design method. The experiment results indicate that this stabilization means is totally passive and offers a high resolution, The maximum quadrature error between dual output signals is 11% when the length of Fabry-Perot cavity changes from 0 to 2μm. The stabilization means can satisfy the stabilization need of optical fiber Fabry-Perot acoustic emission sensor operating point.