DocumentCode :
15421
Title :
Strain variation measurement with short-time Fourier transform-based Brillouin optical time-domain reflectometry sensing system
Author :
Guojie Tu ; Xuping Zhang ; Yixin Zhang ; Zhoufeng Ying ; Lidong Lv
Author_Institution :
Inst. of Opt. Commun. Eng., Nanjing Univ., Nanjing, China
Volume :
50
Issue :
22
fYear :
2014
fDate :
10 23 2014
Firstpage :
1624
Lastpage :
1626
Abstract :
A novel technique to perform dynamic strain measurement with a Brillouin optical time-domain reflectometry (BOTDR) sensing system based on short-time Fourier transform (STFT) is proposed. Unlike traditional frequency scanning methods, the proposed system samples the Brillouin backscattering signal directly after it has been downconverted to the intermediated frequency (IF) region. The Brillouin frequency shift (BFS) of the sensing fibre was reconstructed from the recorded time-domain data continuously without dead-time, which provided a much higher refreshing rate of the strain measurement. Therefore, dynamic strain variation over an optical fibre can be measured with a single-end structure that is more flexible and reliable. A 16.7 Hz strain variation on a 12 m section was successfully detected at the end of a 270 m sensing fibre with 4 m spatial resolution and 45 με uncertainty.
Keywords :
Brillouin spectra; Fourier transform spectroscopy; backscatter; fibre optic sensors; measurement uncertainty; optical time-domain reflectometry; strain measurement; BFS; BOTDR sensing system; Brillouin backscattering signal; Brillouin frequency shift; Brillouin optical time-domain reflectometry; STFT; dynamic strain variation measurement; frequency 16.7 Hz; frequency scanning method; intermediated frequency region; measurement uncertainty; optical sensing fibre; short-time Fourier transform; size 270 m;
fLanguage :
English
Journal_Title :
Electronics Letters
Publisher :
iet
ISSN :
0013-5194
Type :
jour
DOI :
10.1049/el.2014.2470
Filename :
6937259
Link To Document :
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