| 摘要 |
An optical switching system comprises an input terminal for receiving an optical wavelength-division multiplexed (WDM) signal in which optical signals differing in center wavelength i (i = 1 to N) are wavelength-division multiplexed, the optical signal being an optical frequency-shift keying (FSK) signal which is a first optical FSK signal Fi. A splitter splits the optical WDM signal correspondingly to the wavelengths lambda i to generate optical wavelength-corresponding WDM signals Wi. Wavelength extracting circuits extract optical FSK signals Fj (j = 1 to N) pertaining to wavelengths lambda j, to which the wavelengths lambda i are to be switched, from the optical wavelength-corresponding WDM signals Wi to generate optical amplitude-shift keying (ASK) signals Aj pertaining to the wavelengths lambda j to be switched to. Wavelength switches switch the optical ASK signals Aj to second optical FSK signals Fi corresponding to the wavelengths lambda i. A wavelength multiplexer wavelength-multiplexes the second optical FSK signals Fi into an optical switched WDM signal. This optical WD switching system reduces the signal deterioration due to crosstalk by optical signals of wavelengths other than that to be selected when an optical signal of a certain wavelength are being selected by a tunable or a fixed wavelength filter. <IMAGE> |
