| 摘要 |
PROBLEM TO BE SOLVED: To supply an optical signal with a wavelength having a stable level to an optical amplifier for connecting and amplifying outputs only by simply adding a facility to a conventional facility even when the number of wavelengths in the optical wavelength multiplexed signals is lacked with respect to a prescribed number. SOLUTION: Concerning a wavelength detection complementing means 12 provided additionally to an ADM circuit 11 for sampling only the specified optical wavelength as a drop signal from optical wavelength multiplexed signals from the input of a transmission line and adding the optical signal of the same wavelength as this optical signal wavelength as an add signal at the same time, this means detects the wavelength of optical wavelength multiplexed signals sent out of the ADM circuit 11 and when this wavelength is less than the predetermined number of wavelengths, it is solved by providing omitted wavelength information, adding the optical signal of at least one wavelength, complementing the fluctuation of a signal level caused by wavelength omission and sending it to the output of the transmission connected to the optical amplifier. Therefore, it is not necessary to add any function to the ADM circuit 11 and the optical amplifier at the connection destination, either. |
