| 摘要 |
PURPOSE:To spread channels to plural devices simultaneously by employing such constitution that desired reception information is selected by branching a reception signal, and transmission information can be transmitted by converting to an optical signal of unused wavelength and wavelength-multiplexing on a reception signal. CONSTITUTION:A wavelength multiplex optical input signal is branched by a photocoupler 11, and one of branched signals is sent to a means which performs wavelength multiplex and transmission, and others are sent to wavelength selection coherent demodulators 14, 15. The signal is demodulated by selecting desired arbitrary wavelength for a device. When the wavelength to be received shows the one >=2, the number of branching is set at >=3 and the number of wavelength selection coherent demodulators at >=2, and the information of wavelength different at every wavelength selection coherent demodulator is demodulated. The transmission information is converted to the optical signal of wavelength unused in the input signal, and is sent to the means which performs the wavelength multiplex and transmission, and the wavelength multiplex of the transmission signal and the branched input signals are performed by using a photocoupler 12, and it is transmitted. In such a way, it is possible to spread the channels to the plural devices simultaneously. |
