| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a wavelength multiplexed transmission technology for reducing the wavelength band requiring a wavelength division multiplexing-passive optical network (WDM-PON). <P>SOLUTION: A wavelength multiplexing apparatus 100 according to one embodiment of the present invention is equipped with a wavelength multiplexing circuit 212 for multiplexing plurality of differential phase shift keying (DPSK) signals of different wavelengths as downlink optical signals and an optical delay circuit 220 for producing an optical duo-binary signal from the multiplexed DPSK signals. The wavelength multiplexing apparatus 100 is further equipped with an optical receiver for receiving, as incoming optical signals. a plurality of DPSK signals of different wavelengths via the optical delay circuit 220 as an optical duo-binary signal. Thus, since the uplink and downlink optical signals are multiplexed/demultiplexed by the optical delay circuit 220, a dead band generated when using an optical filter is not generated. Furthermore, since DPSK signals or the optical duo-binary signals are utilized for optical signals, a modulation band is reduced approximately by half in comparison with NRZ of an ordinary light intensity signal. <P>COPYRIGHT: (C)2009,JPO&INPIT |
