Patent ID: 6169615
Filing Date: 2001-01-02
Classification: H04J

Abstract:
A wavelength division multiplex optical transmission apparatus in which a plurality of optical signals having different wavelengths are processed by wavelength division multiplexing, and are transmitted through an optical transmission line, the apparatus comprising: an optical sending system having a plurality of optical sending sections to generate and transmit the optical signals having the different wavelengths, a plurality of optical amplifying sections to amplify the optical signals with the wavelengths from the optical sending sections, and a wavelength division multiplexing section to process by the wavelength division multiplexing and output to the optical transmission line the optical signals amplified in the optical amplifying sections; an optical receiving system having a wavelength division demultiplexing section to demultiplex the wavelength division multiplexed optical signals transmitted through the optical transmission line into the optical signals with the wavelengths, and a plurality of optical receiving sections to receive the optical signals demultiplexed in the wavelength division demultiplexing section; and an optical output level control section to control, for the wavelengths, optical output levels of the optical signals output to the optical transmission line through the wavelength division multiplexing section by individually varying amplification factors of the optical amplifying sections in the optical sending system according to transmission distances of the optical signals with the wavelengths.