Open AccessA BOTDA with break interrogation function over 72 km sensing length
Author(s) -
Junhui Hu,
Xuping Zhang,
Yuguo Yao,
Xiaodong Zhao
Publication year - 2013
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.21.000145
Subject(s) - reflectometry , optics , interrogation , robustness (evolution) , fiber optic sensor , image resolution , materials science , interferometry , time domain , optical fiber , physics , computer science , biochemistry , chemistry , archaeology , gene , computer vision , history
A BOTDA with the capacity of break interrogation is proposed and demonstrated experimentally. In our configuration, coherent detection and double sideband probe method are employed to enhance the signal-to-noise ratio (SNR) and to effectively reduce nonlocal effects, respectively. Without amplification, a 72 km sensing range with 5-meter resolution and an estimated temperature uncertainty of 1.8 °C are obtained. Benefiting from the flexible optical configuration, this sensor system has the capacity of break interrogation as a coherent optical time domain reflectometry (COTDR) if there is a break in the fiber under test (FUT). The sensor achieves a dynamic range of 36 dB with a 100 m spatial resolution, which offers an excellent solution for the requisite of two-end-access in BOTDA, and significantly enhances the robustness of the sensing system.