| 摘要 |
PROBLEM TO BE SOLVED: To provide a branching unit for an optical transmission system having a first branch 38 and a second branch 40 individually connected to a main branch 42, the optical transmission system and an operating method of the branching unit 30. SOLUTION: A first directional current flow means 54 and a second directional current flow means 58 are respectively operable to allow currents to flow substantially only in one direction along with the first branch 38 and the second branch 40. Thus, a current flowing from the first branch to the second branch and a current flowing from the second branch to the first branch are substantially prevented and currents are prevented from being simultaneously conducted between the first branch and the main branch and between the second branch and the main branch. |
