Long-range and wide-band vibration sensing by using phase-sensitive OFDR to interrogate a weak reflector array
Zhaopeng Zhang, Xinyu Fan, Zuyuan He
Abstract
In this paper, we propose and experimentally demonstrate a novel quasi-distributed fiber-optic vibration sensing system, which can achieve vibration measurement with a wide frequency response over a long distance. The system is based on phase-sensitive optical frequency domain reflectometry (ϕ-OFDR). The sensing part is a single-mode fiber (SMF) with auxiliary weak reflection points along it. By detecting the auxiliary weak reflection points, we can obtain the waveform of the vibration signal. In the experiments, single-point and multi-point vibrations with a wide-frequency response at 100 km are successfully measured, which validated the proposed system. To the best of our knowledge, this is the first time to realize a wide-band vibration waveform measurement over such a long range by using reflectometry-based sensing system.