| 摘要 |
<P>PROBLEM TO BE SOLVED: To eliminate the need to expand the application range of a PDM compensator or the need for the PDM compensator, in an optical transmission system which uses a single optical fiber transmission line, a bidirectional optical amplifier repeater, and an OADM node device. <P>SOLUTION: A node device is equipped with a means for transmitting and receiving optical signals having a plurality of wavelengths, an optical switch for setting routes of transmission and reception clockwise or counterclockwise by the wavelengths, and a DGD measuring instrument measuring DGD value wavelength characteristics of each of the wavelengths. A clockwise path and a counterclockwise path connecting two node devices differ in distance. When wavelengths are assigned to optical signals transmitted through the clockwise path and counterclockwise path; a first wavelength whose DGD value is smaller than a mean DGD value is assigned to a path having a relatively long distance, and a second wavelength whose DGD value is larger than the mean DGD value is assigned to a path having a relatively long distance according to DGD value wavelength characteristics of the optical fiber transmission line measured by the DGD measuring instrument. <P>COPYRIGHT: (C)2007,JPO&INPIT |
