| 摘要 |
PURPOSE:To reduce the amount of signal processing by providing a specific optical filter among plural nodes to which natural optical wavelength is allocated. CONSTITUTION:When a light signal L1 with optical wavelength lambda31 is sent from a node transmission port 14 to a distributor 12 by means of a node 2a, it is transmitted through I/O ports 11a to 11c to transmission lines 1a, 1d, and 1e. On the signal L1 to the line 1a, since the optical filter 3a does not pass the optical communication of waveform lambda3, a path is not opened to the line 1a side, similarly it is not opened to an 1d side. The signal L1 to the line 1d is branched at a branching junction part 3e-4 by means of an optical filter 3e, inputted to filter elements 3e-1, 3e-2. The element 3e-1 passes the only signal with the wavelength lambda1 and does not pass the signal L1. The element 3e-2 passes the signal L1. The signal L1 passing through an element 3e-2 enters into the node 2c through a branching junction part 3e-3. Thus, the signal processing is reduced. |
