
Fast distributed dynamic strain sensing using a modified gain-profile tracing technique
Author(s) -
Wei Zhu,
M. Li,
Haifei Lu,
Xiaoyan Wen,
Shuo Deng,
Chaojun Jiang
Publication year - 2019
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.27.000816
Subject(s) - demodulation , optics , image resolution , tracing , modulation (music) , computer science , frequency modulation , temporal resolution , materials science , acoustics , physics , telecommunications , bandwidth (computing) , channel (broadcasting) , operating system
Gain-profile tracing (GPT) is a useful strategy of distributed sensing in BOTDA technique for achieving high spatial resolution, which has not been used for the dynamic strain measurement previously. In this paper, we propose a modified gain-profile tracing (MGPT) technique for fast dynamic strain measurement while maintaining the advantage of high spatial resolution. This technique is based on a modified pump pulse modulation scheme and the slope-assisted demodulation method. The time consumption using MGPT technique for a single pump pulse measurement of dynamic strain is less by 25% than the conventional GPT technique. The spatial resolution of our BOTDA system using MGPT technique is 50cm and maximal frequency of dynamic strain detection could be up to 53.5 Hz for 248m sensing length. In the experiments, we measure two vibration events spacing 50 cm with the frequency of 14.0 Hz and 17.0 Hz in a 248 m single-mode fiber. The proposed method is a potential real-time dynamic alternative for distributed structural health monitoring.