Crossconnect apparatus for a coherent transmission system

Claim 1

A crossconnect apparatus comprising: means for inputting a plurality of coherent signals, each including a main signal and a sub-signal placed before said main signal, said sub-signal being modulated by one of a group of modulation methods including a frequency modulation, a phase modulation, an intensity modulation and an amplitude modulation which are different from those applied to the main signal; a wavelength filter, coupled to said inputting means, for extracting a desired signal from said plurality of coherent signals; a header detector, coupled to said wavelength filter, for detecting said sub-signal from said extracted signal; a destination decoder, coupled to said header detector, for extracting destination information from said sub-signal; and an optical switching stage controller, coupled to said destination decoder, for setting a signal path for said extracted signal based on said destination information.