Bidirectional Optical Add-Drop Multiplexer Based on Bragg Gratings and Circulators

We propose and demonstrate a bidirectional optical add-drop multiplexer for use in single-fiber bidirectional networks. With effective use of multiport circulators, fiber-Bragg gratings, and a single amplifier element, the new structure can add and /or drop channels in both directions and achieves more than 16 dB of bidirectional gain. The device utilizes Bragg gratings and light absorbers to remove Rayleigh backscattered and reflected light at the input stage.