三分量全保偏光纤加速度传感器的研究

报道了三分量全保偏光纤加速度传感器的实验研究结果。传感器由6个弹性柱体共同支撑1个质量块构成三分量结构,由3个迈克尔逊全保偏光纤干涉仪共用一个光源组成。光学部分采用全保偏光纤干涉仪结构,消除了干涉光束偏振态随机变化引起的信号衰落,采用光频调制相位载波解调信号处理技术,消除了相位随机漂移引起的信号衰落,从而实现了对加速度信号的稳定检测。传感器的工作频带为5~500 Hz,加速度灵敏度达到660 rad/g,系统最小可测相位差为10-5rad,最小可测加速度达1.5×10-7m/s2,工作频带内加速度灵敏度变化小于2 dB。三轴加速度灵敏度和频率响应曲线与理论分析的结果基本一致。

Research on Three-Component All Polarization-maintaining Fiber Optic Accelerometer

The experimental results of three-component all polarization-maintaining fiber optic accelerometer are presented. The three-component accelerometer is composed of a seismic mass supported by six compliant cylinders and three Michelson all polarization maintaining fiber optic interferometers which share one laser。The all polarization-maintaining fiber optic interferometer structure can prevent signal fading due to random changes in the state of polarization of the guided beams. With phase generated carrier technology, the signal fading caused by random phase-shift in the interferometer is eliminated. Based on these methods, the fiber optic accelerometer attained stable signal. Operating frequency band of the sensor is from 5 Hz to 500 Hz. The acceleration sensitivity in experimental results reaches 660 rad/g. In this system, minimum measurable phase is 10-5 rad and minimum measurable acceleration reaches 1.5×10-7 m/s2. Variation in acceleration sensitivity is not greater than 2 dB in operating frequency band. The results of experiment agree well with the theoretical analysis.