基于波导调制器的全保偏光纤微振动传感器

A vibration sensor using all polarization-maintaining fiber waveguide modulator

为了解决干涉型光纤传感器中光源频率调制深度与干涉仪光程差的相关性,以及压电陶瓷(PZT)调制的高频限制和非线性效应,设计了全保偏光纤马赫一泽德干涉仪结构,引入保偏光纤波导相位调制器替代常见的光源调制及PZT调制,采用低噪声单频保偏光纤激光器作为光源,通过相位载波零差解调方法,实现了微振动信号的保真拾取．通过波导调制器的引入,增加了系统的灵活性和频响范围,并使灵敏度达到了10-5rad／Hz1/2量级。

In interferometric fiber sensors, there are the problems that the dependence between the modulation depth of laser frequency modulation and the optical path difference, and the high frequency restriction and nonlinear effect of PZT modulation. In order to resolve the restriction and ensure the fidelity-pickup of micro-vibration signal, a vibration sensor based on all polarization-maintained fiber Mach-Zednder interferometer is presented, in which a fiber waveguide modulator is set and the single-frequency polarization-maintaining optical fiber laser and the phase generated carrier homodyne demodulation scheme are employed. The use of waveguide modulator increases the flexibility and the frequency response range of the sensor and the sensitivity reaches to 10^-5rad/Hz^1/2.