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Laser Feedback OFDR With High Sensitivity
Journal of Lightwave TechnologyYidong Tan, Jinsong Liu, Yifan Wang
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A flexible multiplexing method of FBG sensors based on OFDR
Optik, 2022Hong-Zhun Liu
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MONITORING OF CONCRETE STRUCTURES USING OFDR TECHNIQUE
AIP Conference Proceedings, 2011Structural health monitoring is a key factor in life cycle management of infrastructures. Truly distributed fiber optic sensors are able to provide relevant information on large structures, such as bridges, dikes, nuclear power plants or nuclear waste disposal facilities. The sensing chain includes an optoelectronic unit and a sensing cable made of one
J. M. Henault +9 more
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Fourier analysis of the complex envelope of the echos in an OFDR
Applied Optics, 1986The Fourier transform of the complex envelope of the echos in an optical frequency domain reflectometer displays discrete lines in the spectrum. The location of each line in the spectrum corresponds to the location of a corresponding reflector along the fiber.
M, Shadaram, R D, Hippenstiel
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Phase-OFDR for distributed disturbance measurement
SPIE Proceedings, 2016We introduce the optical frequency domain reflectometry (OFDR) technique based on intensity modulation frequency sweep measurement for distributed disturbance measurement in optical fibres. By evaluating interferometric Rayleigh scattering changes along the fibre, strain and temperature changes are detected with 100 n(epsilon) sensitivity and 10 mK ...
Sascha Liehr, Katerina Krebber
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Spectral splicing for an OFDR sensing system using a DBR laser
Applied Optics, 2022A spectral splicing method is proposed for an optical frequency domain reflectometry (OFDR) sensing system using a distributed Bragg reflector (DBR) laser. An external cavity tunable laser (ECTL) is used in a conventional OFDR sensing system. There are no reports to our knowledge about using a DBR laser as the light source for an OFDR sensing system. A
Yuanze Xue +4 more
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A dual-ended 400 km OFDR for vibration detection
Measurement Science and Technology, 2022Abstract Optical frequency-domain reflectometer (OFDR) has been widely used in vibration detection because of its unique advantages of simple configuration and high spatial resolution. Based on remote fiber amplification, an unrepeated OFDR is experimentally investigated for vibration detection.
Zujun Qin, Yiwei Hu, Yaoli Yue, Chao Tan
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New details of spun fibers measured with an OFDR
2006 Optical Fiber Communication Conference and the National Fiber Optic Engineers Conference, 2006OFDR signals from spun fibers contain frequency components related to a beating between effective beat length and spin period. Agreement between simulation and measured data allows correct extraction of spin period and effective beat length.
T. Geisler, P. Kristensen, O. Knop
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High accuracy OFDR by coherence compensation method
28th International Conference on Optical Fiber Sensors, 2023We developed a new hardware-linearization type OFDR system that compensates for coherence degradation at an arbitrary position. The system compensates for coherence degradation due to propagation time difference over ±25 m centered at an arbitrary position, ranging from 0 to 150 m.
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Distributed sparse signal sensing based on compressive sensing OFDR
Optics Letters, 2020The maximum detectable vibration frequency of an optical frequency domain reflectometry (OFDR) system is limited by the tunable rate of the laser source. Unlike uniform sampling with the time-resolved method, the sampling frequency is randomly modulated so that the vibration signal applied on the interrogation fiber is sampled by a multi-frequency sub ...
Shuai, Qu +6 more
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