Distributed incomplete polarization-OTDR based on polarization maintaining fiber for multi-event detection

A new scheme for the distributed intrusion detection system based on the polarization optical time domain reflectometry (POTDR) for multi-event detection is proposed in this paper. In the scheme, a polarization maintaining fiber is employed as the distributed pressure sensor instead of the single mode fiber. The working principle of the system is described in detail, and an experimental system is set up to confirm the ability to detect several intrusion events happened at the same time along the sensing fiber by measuring the polarization mode coupling coefficient caused by the pressure and three simulated events. And from the final experimental result denoised using wavelet transformation, the three intrusion events can be significantly detected.