Distributed intrusion monitoring system with fiber link backup and on-line fault diagnosis functions

Abstract

A novel multi-channel distributed optical fiber intrusion monitoring system with smart fiber link backup and on-line fault diagnosis functions was proposed. A 1×N optical switch was intelligently controlled by a peripheral interface controller (PIC) to expand the fiber link from one channel to several ones to lower the cost of the long or ultra-long distance intrusion monitoring system and also to strengthen the intelligent monitoring link backup function. At the same time, a sliding window auto-correlation method was presented to identify and locate the broken or fault point of the cable. The experimental results showed that the proposed multi-channel system performed well especially whenever any a broken cable was detected. It could locate the broken or fault point by itself accurately and switch to its backup sensing link immediately to ensure the security system to operate stably without a minute idling. And it was successfully applied in a field test for security monitoring of the 220-km-length national borderline in China.

Keywords

Multi-channel / distributed optical fiber sensing system / cable fault diagnosis / auto-correlation

References

[1] Juarez J C, Maier E W, Choi K N, Taylor H F. Distributed fiber-optic intrusion sensor system. Journal Of Lightwave Technology, 2005, 23(6): 2081-2087.

[2] Zhang Z Y, Bao X Y. Distributed optical fiber vibration sensor based on spectrum analysis of Polarization-OTDR system. Optics Express, 2008, 16(14): 10240-10247.

[3] Zhang X, Lu Y, Wang F, Liang H, Zhang Y. Development of fully-distributed fiber sensors based on Brillouin scattering. Photonic Sensors, 2011, 1(1): 54-61.

[4] Rao Y, Luo J, Ran Z, Yue J, Luo X, Zhou Z, . Long-distance fiber-optic φ-OTDR intrusion sensing system. Proc. SPIE, 2009, 7503(1): 75031O-1-75031O-4.

[5] Wang J, Jia X, Rao Y, Wu H. Phase-sensitive optical time-domain reflectometer based on bi-directional Raman amplification. Acta Physica Sinica, 2013, 62(4): 044212-1-044212-5.

[6] Rao Y J. Study on fiber-optic low-coherence interferometric and fiber Bragg grating sensors. Photonic Sensors, 2012, 1(4): 382-400.

[7] Nikles M U, Du H H, Wang A. Long-distance fiber optic sensing solutions for pipeline leakage, intrusion and ground movement detection. Proc. SPIE, 2009, 7316(1): 731602-1-731602-13.

[8] Peng F, Wang Z, Rao Y, Jia X. 106 km fully-distributed fiber-optic fence based on P-OTDR with 2nd-order Raman amplification. National Fiber Optic Engineers Conference, 2013, Anaheim: California United States, 1-3.

[9] Yeh C, Chi S. Self-protection against fiber fault for ring-based power-splitting passive optical networks. Optical Engineering, 2008, 47(2): 020501-1-020501-3.

[10] Shin W, Yu B A, Lee Y L, Eom T J, Noh Y C. Flexible fiber fault detecting technique based on wavelength swept fiber laser for passive optical network. Conference on Lasers & Electro Optics & The Pacific Rim Conference on Lasers and Electro-Optics, 2009 1-2.