Patent ID: 7164858

Claim:
An optical transmission system for transmitting a broadband optical signal and a wavelength-multiplexed optical signal, the optical transmission system comprising: a plurality of receivers; a transmitter comprising: a broadband optical transmitter for outputting the broadband optical signal; an optical filter for passing a predetermined wavelength bandwidth optical signal of the broadband optical signal output from said broadband optical transmitter based on a predetermined wavelength bandwidth; a wavelength multiplexing optical transmitter for outputting the wavelength-multiplexed optical signal including a plurality of optical signals having wavelengths that are different from the predetermined wavelength bandwidth of said optical filter; and a coupler for coupling the predetermined wavelength bandwidth optical signal passed through said optical filter with the wavelength-multiplexed optical signal outputted from said wavelength multiplexing optical transmitter; an optical amplifier for amplifying the predetermined wavelength bandwidth optical signal and the wavelength-multiplexed optical signal coupled by said coupler, and outputting an amplified optical signal; and a wavelength router, including a plurality of output ports, for wavelength branching the amplified optical signal, and outputting branched optical signals from said output ports to said receivers, respectively, depending on wavelengths of the branched optical signals, wherein said wavelength router distributes the predetermined wavelength bandwidth optical signal simultaneously to each of said output ports in the branched optical signals, and outputs optical signals obtained by branching the wavelength-multiplexed optical signal based on a wavelength thereof to corresponding output ports in the branched optical signals, outputs the branched optical signals to said corresponding output ports based on a wavelength uniquely assigned to each of said output ports, and has a periodic branching characteristic with which the amplified optical signal is branched, separate from the uniquely-assigned wavelengths, based on a periodic wavelength which appears at a periodic interval with respect to each of the uniquely-assigned wavelengths for output to said output ports, the wavelength bandwidth of the predetermined wavelength bandwidth optical signal passed through said optical filter at least includes the periodic wavelengths corresponding to said output ports and does not include the uniquely-assigned wavelengths, and the wavelength of the wavelength-multiplexed optical signal transmitted from said wavelength multiplexing optical transmitter is selected from the uniquely-assigned wavelengths.