Title :
Distributed Vibration Sensor Based on Coherent Detection of Phase-OTDR
Author :
Lu, Yuelan ; Zhu, Tao ; Chen, Liang ; Bao, Xiaoyi
Author_Institution :
Dept. of Phys., Univ. of Ottawa, Ottawa, ON, Canada
Abstract :
We developed a distributed vibration sensor by using heterodyne detection and signal processing of moving averaging and moving differential for the phase optical time domain reflectometry system. The broadband acoustic frequency components generated by pencil-break vibration have been measured and identified in location by our distributed vibration sensor for the first time. Pencil break measurement is a standard technique to emulate the acoustic emission of cracks in concrete or steel bridges for early crack identification. The spatial resolution is 5m and the highest frequency response is 1 kHz, which is limited by the trigger frequency of data acquisition card. This new sensing system can be used for vibration detection of health monitoring of various civil structures as well as any dynamic monitoring requirement.
Keywords :
acoustic emission; bridges (structures); concrete; condition monitoring; crack detection; data acquisition; distributed sensors; fibre optic sensors; frequency response; heterodyne detection; moving average processes; optical time-domain reflectometry; signal processing; structural engineering; vibration measurement; acoustic emission; broadband acoustic frequency component; coherent detection; concrete; crack identification; data acquisition card; distributed optical fiber sensor; distributed vibration sensor; frequency response; heterodyne detection; moving averaging method; moving differential method; pencil break vibration measurement; phase optical time domain reflectometry; phase-OTDR; signal processing; spatial resolution; steel bridge; trigger frequency; vibration detection; Frequency response; Optical fiber polarization; Optical fiber sensors; Signal to noise ratio; Vibrations; Distributed optical fiber sensor; frequency response; pencil-break; phase-sensitive OTDR; vibration;
Journal_Title :
Lightwave Technology, Journal of
DOI :
10.1109/JLT.2010.2078798
