High-Pass Filtering for Accuracy Enhancement in Dark-Pulse Brillouin Optical Time Domain Analysis

In this letter, we demonstrate a simple technique aimed to enhance the accuracy in dark-pulse Brillouin optical time-domain analysis (BOTDA) sensors. Modeling the stimulated Brillouin scattering in the frequency domain, we show that the degrading features related to the pump background can be removed by applying a high-pass filter to the raw data, at the cost of some degradation of the signal-to-noise ratio. A numerical analysis, as well as experimental tests carried out at 20-cm spatial resolution, validate the proposed technique.

[1]  Romeo Bernini,et al.  Stimulated Brillouin scattering modeling for high-resolution, time-domain distributed sensing. , 2007, Optics express.

[2]  B. Colpitts,et al.  Distributed sensor based on dark-pulse Brillouin scattering , 2005, IEEE Photonics Technology Letters.

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

[4]  A. Minardo,et al.  Spatial Resolution Enhancement in Preactivated BOTDA Schemes by Numerical Processing , 2012, IEEE Photonics Technology Letters.

[5]  Kinzo Kishida,et al.  Pulse pre-pump method for cm-order spatial resolution of BOTDA , 2005, International Conference on Optical Fibre Sensors.

[6]  Kazuo Hotate,et al.  Measurement of Brillouin Gain Spectrum Distribution along an Optical Fiber Using a Correlation-Based Technique : Proposal, Experiment and Simulation (Special Issue on Optical Fiber Sensors) , 2000 .

[7]  R. Bernini,et al.  Distributed Sensing at Centimeter-Scale Spatial Resolution by BOFDA: Measurements and Signal Processing , 2012, IEEE Photonics Journal.

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

[10]  Luigi Zeni,et al.  High-Pass Filtering for Accurate Reconstruction of the Brillouin Frequency Shift Profile From Brillouin Optical Frequency Domain Analysis Data , 2018, IEEE Sensors Journal.

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

[12]  M. Facchini,et al.  Distributed sensing using stimulated Brillouin scattering : towards ultimate resolution , 1997 .