| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical interface automatic changeover system switching automatically an active system transmission line or a standby system transmission line connecting to an optical interface without terminating a main signal and without the need for installation of an excess optical fiber transmission line. SOLUTION: When a transmission line selection judging section 6a detects a fault in a transmission line 3d, an optical switch 2a is switched to select a standby system transmission line 4 from an active system transmission line 3. Then a transmission line information transmission section 5a sends prescribed transmission line selection information, which is synthesized with a main signal by a wavelength division multiplex(WDM) coupler 9a and the resulting signal is fed to a WDM coupler 10b. The WDM coupler 10b distributes the received transmission line selection information to a transmission line selection judging section 6b. The transmission line selection discrimination section 6b switches an optical switch 2b based on the received transmission line selection information so as to select the standby system transmission line 4 from the active system transmission line 3. |
