Subcarrier-multiplexed signaling based add/drop multiplexer in optical FDM networks

To guarantee the transparency of optical FDM networks, both the link and node are fully operated in optical domain. This requires true sense of optical node, of which both the function and the signaling for the control are optically realized. Compared with a dedicated signaling channel on a common wavelength, subcarrier multiplexing (SCM) offers higher cost-savings as well as wavelength resource efficiency. An optical implementation of SCM-controlled add/drop multiplexer, which performs one of the fundamental node functions, is proposed and experimentally demonstrated. It is composed of a pair of arrayed-waveguide-gratings and optical switches driven by SCM-control signals. It is shown that this configuration is suitable for multigigabits optical FDM networks due to the capability of high-speed operation.