Patent ID: 7844177
Filing Date: 2010-11-30
Classification: H04J,H04Q

Abstract:
1. An optical signal changeover device which has a plurality of input ports and a plurality of output ports, and performing path changeovers of optical signals received at the input ports and outputted from the output ports, the optical signal changeover device comprising a plurality of optical bifurcating units to bifurcate a plurality of optical signals respectively and to send bifurcated optical signals to first and second optical switches; a path changeover unit provided with the first and second optical switches, to change over the paths of the optical signals sent from the optical bifurcating units; a plurality of fixed wavelength conversion units to perform conversion to a predetermined fixed wavelength for each of optical signals outputted from the first and second optical switches, first and second wavelength multiplexers provided corresponding to the first and second optical switches, respectively, to perform wavelength-multiplexing of the optical signals outputted from the fixed wavelength conversion units, an optical signal selection unit to select the optical signals outputted either from the first wavelength multiplexer or from the second wavelength multiplexer; a wavelength demultiplexer to demultiplex the wavelength-multiplexed optical signals selected by the optical signal selection unit and to output optical signals after demultiplexing; a monitoring control unit to exercise monitoring of the status at the path changeover unit and to control operation of the optical signal selection unit; and a system monitoring control unit to exercise monitoring and control over the entire system wherein the monitoring control unit controls the optical signal selection unit to select either the optical signals outputted from the first wavelength multiplexer or the optical signals outputted from the second wavelength multiplexer based on the status at the path changeover unit.