Remote fiber optic switch powered by light for robust interrogation of fiber Bragg grating sensor networks

In this work, a remote fiber optic switch powered by light is demonstrated experimentally. This fiber optic switch is powered by a photovoltaic power converter illuminated by a Raman laser. The switch can operate at distances up to 100 km. This switch is used to develop a remote resilient fiber Bragg grating (FBG) multiplexing network interrogated by a commercial FBG interrogator. In the proposed set-up the switch selects the branch of the FBG network located 50 km away from the interrogation unit in order to enable a two-way interrogation path for each sensor to prevent connection failures or fiber breakages. (paper)