|

Distributed fiber-optic acoustic sensor based on a Sagnac interferometer with detection of exposure at the threshold signal level

Authors: Choban T.V.
Published in issue: #9(62)/2021
DOI: 10.18698/2541-8009-2021-9-732


Category: Instrument Engineering, Metrology, Information-Measuring Instruments and Systems | Chapter: Laser and opto-electronic systems

Keywords: оptical fiber, acoustic sensor, security system, Sagnac interferometer, fiber optic cable, wavelength multiplexing, polling algorithm
Published: 06.09.2021

The operation principle of a distributed fiber-optic acoustic sensor based on the Sagnac interferometer is described and the prospects of its application for solving problems of extended objects protection are demonstrated. A circuit of such a sensor based on two loops created using wavelength multiplexing is proposed, which makes it possible to implement a sensor system based on four cable fibers, which provides compactness and simplifies its installation along the protected perimeter. An algorithm for processing the data obtained from the sensor is also presented, which ensures high accuracy in determining the location of the impact: according to the results of laboratory experiments with a total length of the sensor fiber of 50 km, the error was 13 m.


References

[1] Szustakowski M., Ciurapinski W., Palka N. et al. Recent development of fiber optic sensor for perimeter security. Proc. IEEE 35th Annual 2001 Int. Carnahan Conf. on Security Technology, 2001, pp. 142–148. DOI: https://doi.org/10.1109/CCST.2001.962826

[2] Stepanov K.V., Zhirnov A.A., Chernutsky A.O. et al. The sensitivity improvement characterization of distributed strain sensors due to weak fiber Bragg gratings. Sensors, 2020, vol. 20, no. 22, art. 6431. DOI: https://doi.org/10.3390/s20226431

[3] Huang Y., Wang Q., Shi L. et al. Underwater gas pipeline leakage source localization by distributed fiber optic sensing based on particle swarm optimization tuning of the support vector machine. Appl. Opt., 2016, vol. 55, no. 2, pp. 242–247. DOI: https://doi.org/10.1364/ao.55.000242

[4] Choban T.V., Zhirnov A.A., Chernutsky A.O. et al. Φ-OTDR based on tunable Yb-Er: phosphate glass laser. J. Phys.: Conf. Ser., 2019, vol. 1410, no. 1, art. 012108. DOI: https://doi.org/10.1088/1742-6596/1410/1/012108

[5] Choban T.V., Zhirnov A.A., Stepanov K.V. et al. Distributed acoustic sensor based on Sagnac interferometer with zero frequencies poll. Foton-Ekspress, 2021, no. 2, pp. 14–17 (in Russ.).

[6] Huang J., Chen Y., Peng H. et al. A 150 km distributed fiber optic disturbance location sensor with no relay based on the dual-Sagnac interferometer employing time delay estimation. Opt. Commun., 2021, vol. 479, art. 126420. DOI: https://doi.org/10.1016/j.optcom.2020.126420

[7] Song Q., Zhou P., Peng H. et al. Improved localization algorithm for distributed fiber optic sensor based on merged Michelson-Sagnac interferometer. Opt. Express, 2020, vol. 28, no. 5, pp. 7207–7220. DOI: https://doi.org/10.1364/OE.384728

[8] Choban T.V., Koshelev K.I., Khan R.I. et al. [Distributed fiber optical vibration sensor based on Sagnac interferometer]. Sb. nauch. tr. XXXI Mezhd. konf. Lazery v nauke, tekhnike, meditsine [Proc. XXXI Int. Conf. Lasers in Science, Technics, Medicine]. Moscow, RNTORES im. A.S. Popova Publ., 2020, pp. 99–103 (in Russ.).

[9] McAulay A.D., Wang J. A Sagnac interferometer sensor system for intrusion detection and localization. Proc. SPIE, 2004, vol. 5435. DOI: https://doi.org/10.1117/12.542834

[10] Udd E., ed. Fiber optic sensors. An introduction for engineers and scientists. Wiley, 2011. (Russ. ed.: Volokonno-opticheskie datchiki. Vvodnyy kurs dlya inzhenerov i nauchnykh rabotnikov. Moscow, Tekhnosfera Publ., 2008.)

[11] Wang Y., Yuan H., Liu X. et. al. A comprehensive study of optical fiber acoustic sensing. IEEE Access, 2019, vol. 7, pp. 85821–85837. DOI: https://doi.org/10.1109/ACCESS.2019.2924736