| 摘要 |
PURPOSE:To immediately restore a circuit when a fault is generated in eighter one of units by arranging one optical fiber and one light reproducing repeater for changing a reproducing/repeating transmission direction optionally by a control signal outputted from a terminal equipment in a normal reference optical repeating transmission system. CONSTITUTION:A pair of optical fibers l, 2 to be transmission media are arranged between the terminal equipments 7, 8, current light reproducing repeaters 4, 5 are arranged on the optimum and optional positions of the optical fibers 1, 2 and the optical fiber 1 and the light reproducing repeater 4 attain communication from one terminal equipment 7 to the other 8. On the other hand, the optical fiber 2 and the light reproducing repeater 5 attain communication from the terminal equipment 8 to the terminal equipment 7 and a reproducing direction optionally changing light reproducing repeater 6 for backup which can optionally change the reproducing repeating direction is formed as a common redundant communication system for two-directional communication. Even if a fault is generated in the current optical fiber or the current light reporducing repeater, the circuit is immediately restored by using the backup circuit. |
