| 摘要 |
PURPOSE:To secure the synchronization of each reception information string by controlling a wavelength of an optical signal between active and standby optical transmission lines with the uninterruptible transmission line changeover system. CONSTITUTION:A transmission information string 100 being a changeover object is sent in parallel between an active optical transmission line 7 and a standby optical transmission line 8, and after the synchronization of reception information strings 200, 300 is secured, the lines are selected by an uninterruptible transmission line changeover means and a receiver side detects a phase difference between the reception information strings 200, 300 by an information string phase difference detection means 13. An optical wavelength change control means 5 generates each optical wavelength change signal for active and standby systems adaptive to the phase difference signal so that the sender side make the phase difference zero and an electrooptic conversion/optical wavelength change means 4 for the active and the standby system converts the electric signal of the transmission information string 100 into an optical signal according to each optical wavelength change signal and changes the wavelength of each transmission light and sends the result to the active and standby optical wavelength transmission lines 7, 8. Thus, the transmission capacity is not affected in comparison with a conventional logic synchronization system by the memory control requiring the storage capacity proportional to the transmission capacity. |
