Patent ID: 7295779

Claim:
A wavelength division-multiplexing optical transmission system comprises: a plurality of optical transmitters for producing optical signals respectively, a wavelength on each of wavelength grids being defined as a center wavelength of each optical signal, said wavelength grids on which laser wavelengths are allocated at grid intervals of 100 GHz, the wavelength interval between respective channels being spaced apart at least two grid intervals, the band of each channel covering at least two grid intervals including neighboring grid intervals; a wavelength multiplexer for receiving optical signals output from said plurality of optical transmitters, multiplexing wavelengths of said optical signals, and then outputting multiplexed optical signals; a wavelength demultiplexer for receiving optical signals transmitted output from said wavelength multiplexer, demultiplexing wavelengths of said optical signals, and then outputting optical signals having different wavelengths; and a plurality of optical receivers for converting optical signals, each with a predetermined wavelength range, output from said wavelength demultiplexer, into electrical signals, wherein said wavelength interval between a first optical transmitter and a second optical transmitter is a first number of grids, and said wavelength interval between said first optical transmitter and a third optical transmitter is a second number of grids, the second number being different from the first number and being greater than two.