| 摘要 |
PROBLEM TO BE SOLVED: To provide an automatic dispersion compensation optical transmission system capable of optimally setting the dispersion compensation amount of a DCF(dispersion compensation fiber) by a transmission section and being applied to the automatic changeover of a channel. SOLUTION: It this optical transmission system, since the wavelengths of optical main signals (a) generated in an optical transmission part 10 and optical signals (b) for supervisory and control are different and the difference is generated in the propagation speed of a transmission line, phase difference corresponding to a transmission distance is generated also in low frequency pulse signals superimposed to the optical main signals (a) and the optical signals (b) for the supervisory and the control respectively. In a linear repeater 11, the distance of the transmission section is specified by detecting the phase difference ϕ from the one (a', b') photoelectrically converted after branching in a WDM coupler 13 of the optical signals transmitted from the optical transmission part 10 in a phase difference detection circuit 18 and further, optical matrix switches 22 and 22' as the optical branching connection setting means of two branches between which the DCFs 24 and 25 of difference dispersion compensation amounts are interposed and connected are controlled by a control circuit 26 based on the phase difference ϕ in a dispersion compensation part. |
