Shi Jinhui, Guang Dong, Li Shili, Wu Xuqiang, Zuo Cheng, Gui Lei, Zhang Wujun, Zhang Guosheng, Ge Qiang, Zhang Gang, Wang Rui, Yu Benli
Opt Lett. 2021 Nov 15;46(22):5643-5646. doi: 10.1364/OL.444091.
Phase-difference sensing technology (PDST) has been applied to strain measurement, but its completeness is destroyed by the phase-difference measurement range. A scheme that can realize the completeness of the PDST for low-frequency strain interrogation is proposed. It is built on dual-interferometers and the elliptic-fitting algorithm. To break the measurement range limitation (0, ), a phase compensation setting is applied. The experimental results demonstrate that the method can obtain low-frequency strain signals, and the low-frequency signal whose phase amplitude is greater than is recovered. The scheme is an efficient and complete method for measuring the strain of low-frequency optical fiber length, which could be applied to low-frequency seismic wave monitoring and rock deformation detection.
相位差传感技术（PDST）已应用于应变测量，但其完整性因相位差测量范围而被破坏。提出了一种可实现用于低频应变询问的PDST完整性的方案。该方案基于双干涉仪和椭圆拟合算法构建。为突破测量范围限制（0，），应用了相位补偿设置。实验结果表明，该方法能够获取低频应变信号，且恢复了相位幅度大于的低频信号。该方案是一种测量低频光纤长度应变的高效且完整的方法，可应用于低频地震波监测和岩石变形检测。
