Optical communication system
AssigneeNippon Sheet Glass Co., Ltd.
InventorsMasahiro Oikawa, Ken Yamashita, Chandrasekhar Roychoudhuri, Vladimir V. Serikov
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Abstract
An optical communication system is designed to suppress the generation of cross talk even in the case of small wavelength spacing and high bit-rate modulation. An Nth order harmonic generating device where N is an integer of 2 or larger is positioned before a demultiplexer to upconver the frequency or down convert the wavetlength of the light wave by N times. The frequency spacing between the carriers is increased and allows easier separation of the optical signal and permits denser WDM channels and/or higher data rate per channel. In addition, Si or GaAs based photodiodes may be used instead of InP based photodiodes since the 1550 nm bands are converted to 780 nm bands.
Claims8
An optical communication system comprising:
- a plurality of optical sources generating carriers having unique WDM wavelengths, the same number of optical modulators independently modulating the amplitudes of said carriers, a wavelength multiplexer multiplexing said modulated carriers to form a multiplexed wave, an optical fiber propagating said multiplexed wave, a wavelength demultiplexer separating said propagated wave to a plurality of modulated carriers with different wavelengths, and a plurality of optical detectors detecting said separated carriers and converting to electrical signals,
- wherein an N-th order harmonic generator (N is an integer larger than 1) for multiplying frequencies of said carriers having unique WDM wavelengths is inserted at the front end of said demultiplexer at the receiving station.
Dependencies are inferred from the claim text.