| 摘要 |
PURPOSE:To reduce the cost of transmission system by directly connecting transmission equipments constituting duplicate system through a metallic line in the optical loop transmission system of the duplicate system. CONSTITUTION:A station (n) consists of a master equipment 1n of the system 1 and a master equipment 2n of the system 2 and the master equipments 1n, 2n are connected respectively to transmission equipments 3n, 4n of each system. The transmission equipments 3n, 4n of the systems 1, 2 of the station (n) are connected by the metallic line 5n and the stations (n) and 1 are connected by an optical transmission line 6n. Since no expensive optical transmission module is required for the transmission between the transmission equipments of the systems 1, 2 in the stations 1, 2 ... n in this way, the cost of system is reduced. |
