Distributed and dynamic monitoring of 4km/sec waves using a Brillouin fiber optic strain sensor

We report a Brillouin-based fully distributed and dynamic monitoring of a strain wave, propagating at a speed of ~4km/sec in a 6m long fiber. Using an audio speaker, a mechanical impulse was introduced to one end of a 6m long optical fiber, initiating a strain wave propagating towards the other fixed end of the fiber. Employing a simplified version of the Slope-Assisted Brillouin Optical Time Domain Analysis (SA-BOTDA) technique, the whole length of the fiber was interrogated every 1μs (before averaging). A dynamic spatially and temporally continuous map of the strain was obtained, from which the wave velocity could be deduced. With a trade-off among sampling rate, range and signal to noise ratio, kHz sampling rates and hundreds of meters of range can be covered with spatial resolutions down to a few centimeters.

[1]  Anthony W. Brown,et al.  Dark-Pulse Brillouin Optical Time-Domain Sensor With 20-mm Spatial Resolution , 2007, Journal of Lightwave Technology.

[2]  Jian Wang,et al.  SBS-Based Fiber Optical Sensing Using Frequency-Domain Simultaneous Tone Interrogation , 2011, Journal of Lightwave Technology.

[3]  Ander Zornoza,et al.  Dynamic BOTDA measurements using Brillouin phase-shift , 2012, Other Conferences.

[4]  X. Bao,et al.  Differential pulse-width pair BOTDA for high spatial resolution sensing. , 2008, Optics express.

[5]  Moshe Tur,et al.  Distributed Brillouin sensing with sub-meter spatial resolution: modeling and processing. , 2011, Optics express.

[6]  Kazuo Hotate,et al.  Monitoring Aircraft Structural Health Using Optical Fiber Sensors , 2008 .

[7]  Stephen P. Timoshenko,et al.  Vibration problems in engineering , 1928 .

[8]  R. Kashyap.  Fiber Bragg Gratings , 1999 .

[9]  Moshe Tur,et al.  Fast and distributed high resolution Brillouin based fiber optic sensor , 2013, 2013 Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference (OFC/NFOEC).

[10]  M. Tur,et al.  High spatial resolution distributed sensing in optical fibers by Brillouin gain-profile tracing. , 2010, Optics express.

[11]  Luc Thévenaz,et al.  High Spatial and Spectral Resolution Long-Range Sensing Using Brillouin Echoes , 2011 .

[12]  M. Froggatt,et al.  High-spatial-resolution distributed strain measurement in optical fiber with rayleigh scatter. , 1998, Applied optics.

[13]  Zuyuan He,et al.  High-repetition-rate distributed Brillouin sensor based on optical correlation-domain analysis with differential frequency modulation. , 2011, Optics letters.

[14]  Moshe Tur,et al.  Fast Brillouin Optical Time Domain Analysis for dynamic sensing. , 2012, Optics express.

[15]  Moshe Tur,et al.  BOTDA Measurements in the Presence of Fiber Vibrations , 2012 .

[16]  T. Horiguchi,et al.  Distributed-temperature sensing using stimulated Brillouin scattering in optical silica fibers. , 1990, Optics letters.

[17]  Luc Thévenaz.  Inelastic Scatterings and Applications to Distributed Sensing , 2011 .

[18]  Dapeng Zhou,et al.  Distributed vibration sensing with time-resolved optical frequency-domain reflectometry. , 2012, Optics Express.

[19]  Liang Chen,et al.  Recent Progress in Distributed Fiber Optic Sensors , 2012, Sensors.

[20]  Brooks A. Childers,et al.  Use of 3000 Bragg grating strain sensors distributed on four 8-m optical fibers during static load tests of a composite structure , 2001, SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring.

[21]  M. Tur,et al.  Slope-assisted fast distributed sensing in optical fibers with arbitrary Brillouin profile. , 2011, Optics express.