Bidirectional optical add/drop multiplexer for single-fiber metro networks

Single-fiber bidirectional ring networks (SFBRNs) have received attention due to their cost-effectively enhanced capacity and possibility of self-healing characteristics. A bidirectional optical add/drop multiplexer (BOADM) is a key element in realizing such SFBRNs. Many types of BOADM devices have been demonstrated using arrayed-waveguide gratings (AWGs) and optical circulators (OCs) combined with fiber Bragg gratings (FBGs). Among these, the OC-FBG-based BOADMs are promising due to their low crosstalk, good Rayleigh backscattering suppression and flexible add/drop scheme. However, these OC-FBG-based structures still suffer from high loss and high component count and they do not provide any signal amplification. In this paper, we report a new BOADM, which has a simple configuration, low crosstalk and provides gains of 16 dB for bidirectional signals using a single amplifier element. The device uses multiport OCs and FBGs