基于时分外差法检测的非对称薄壁壳型光纤一维地震波检波器

A One-dimensional Asymmetric Fiber Optical Acceleration Geophone with Thin-walled Shell Based on Heterodyne Demodulation

研制了基于时分外差法检测的非对称薄壁壳型光纤一维地震波检波器，该检波器易于扩展为三轴分立式地震波检波器，具有检测动态范围大，易于构成大规模时分复用传感网络的优点。建立了非对称地震波检波器的理论模型，分析了各结构参数对其灵敏度的影响；搭建了基于光学同步参考信号的时分外差法测试系统，进行了外差系统的稳定性测试，测量了地震波检波器的频响曲线，结果表明外差系统测量信号波动小于0．1dB；工作频段20～800Hz内加速度平均灵敏度为28．5dBrerad／g，与理论仿真结果基本吻合。

The designed acceleration geophone can be used for a three-discrete-axes fiber- optic vector geophone with time division multiplexing （TDM） technology. Combined with the heterodyne detection technique, it has the characteristics of large dynamic range and suitable for large-scale optical fiber hydrophone array network. The theoretical model of the asymmetric structure was proposed, and the inf analyzed. Using optical sync reference its stability was tested. The results experimental acceleration sensitivity is Hz, which basically agrees with the th luences of different parameters on its sensitivity were signal, a heterodyne detection system was constructed and show the fluctuation is less than 0. 1 dB, and the 28. 5 dB re rad/g in the operating frequency of 20-800 eoretical analysis.