Wavelength demultiplexer for optically amplified WDM submarine cable system

The wavelength demultiplexer, using cascaded optical fiber gratings and circulators, was proposed and developed for application to optically amplified wavelength-division multiplexing (WDM) submarine cable systems with 100 GHz channel spacing. Our proposed demultiplexer cannot only achieve high wavelength selectivity, small excess loss and effective allocation of dispersion compensation fibers for each channel, but also be upgraded without affecting other existing channels. By using this: demultiplexer, it has been successfully confirmed that 8 WDM channels were demultiplexed even after 6,000 km transmission including separate compensation of accumulated chromatic dispersion in each channel.