| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical transmission system for reducing the difference in a Raman gain between an uplink and a downlink with respect to a system configuration for performing Raman amplification with a Raman amplifier common to the respective lines. <P>SOLUTION: In this optical transmission system, a plurality of transmission sections using mixed transmission lines with positive distributed fibers and negative distributed fibers combined are set about the uplink and the downlink. When excitation light generated by the Raman amplifier common to the respective lines is supplied to the transmission section of one line using a mixed transmission line 10N wherein average wavelength dispersion in the section is negative and the other transmission section using a mixed transmission line 10P wherein average wavelength dispersion in the section is positive, the lengths of the respective negative distributed fibers 12N and 12P are made to be almost equal by applying the negative distributed fibers 12N and 12P with different wavelength dispersion values as positive and negative mixed transmission lines 10N and 10P used in the transmission sections of the respective lines. <P>COPYRIGHT: (C)2003,JPO |
