We present a remote Michelson interferometric phase sensor based on dual-core fiber transmission and linear phase demodulation. The former allows for synchronous transmission of both sensing signal and reference lights, enabling efficient suppression for the environmental disturbances along the transmission link and for the incoherent phase noise between the two lights. The latter is conducted by two optical phase-locked loops, one of which consists of a fiber stretcher that is used to eliminate the residual phase noises, thus stabilizing the operation point while the other relies on a phase modulator that is used to track the remote phase changes, thus achieving a highly linearized phase demodulation. A remote phase sensing over a 20 km fiber link with less than 3% nonlinear phase error over $3\pi$ range has been readily realized, corresponding to more than 10 times extension in a linear phase demodulation range. The proposed system shows great potential in the field of remote phase sensing for a variety of physical quantities.

中文翻译：

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基于双芯光纤传输和线性相位解调的远程迈克尔逊干涉相位传感器

我们提出了一种基于双芯光纤传输和线性相位解调的远程迈克尔逊干涉相位传感器。前者允许传感信号和参考光的同步传输，从而能够有效抑制传输链路上的环境干扰和两个光之间的非相干相位噪声。后者由两个光学锁相环传导，其中一个由光纤拉伸器组成，用于消除残余相位噪声，从而稳定工作点，而另一个依赖于用于跟踪远程信号的相位调制器。相位变化，从而实现高度线性化的相位解调。20 公里光纤链路上的远程相位感测，非线性相位误差小于 3%，超过$3\pi$范围已经很容易实现，对应于线性相位解调范围的 10 倍以上扩展。所提出的系统在各种物理量的遥感相位传感领域显示出巨大的潜力。