Open AccessFast coarse-fine locating method for φ-OTDR
Author(s) -
Xuanwei Mei,
Huanhuan Liu,
Ge Yu,
Yuying Shao,
Tianyu Qian,
Chengbo Mou,
Longbao Lv,
Tingyun Wang
Publication year - 2018
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.002659
Subject(s) - optical time domain reflectometer , optics , heterodyne detection , heterodyne (poetry) , vibration , computer science , fiber optic sensor , optical fiber , signal (programming language) , time domain , signal processing , distributed acoustic sensing , acoustics , fiber optic splitter , physics , telecommunications , computer vision , laser , radar , programming language
We proposed and demonstrated a coarse-fine method to achieve fast locating of external vibration for the phase-sensitive optical time-domain reflectometer (φ-OTDR) sensing system. Firstly, the acquired backscattered traces from heterodyne coherent φ-OTDR systems are spatially divided into a few segments along a sensing fiber for coarse locating, and most of the acquired data can be excluded by comparing the phase difference between the endpoints in adjacent segments. Secondly, the amplitude-based locating is implemented within the target segments for fine locating. By using the proposed coarse-fine locating method, we have numerically and experimentally investigated a distributed vibration sensor based on the heterodyne coherent φ-OTDR system with a 50-km-long sensing fiber. We find that the computation cost of signal processing for locating is significantly reduced in the long-haul sensing fiber, showing a potential application in real-time locating of external vibration.