Patent ID: 7181095

Claim:
Apparatus for adding wavelengths to a WDM signal, said apparatus comprising: an optical combination structure that combines a set of N/P wavelengths into a single combined optical signal while maintaining a linear orthogonal polarization state for pairs of said wavelengths and while adding optical noise incoherently to minimize optical noise; wherein P is greater than one, N is a total number of wavelengths to be added to said WDM signal and where each of said N/P wavelengths are coupled to said optical structure by separate inputs; a first optical device having P input ports that combines said single combined output signal at an input at each of said P input ports into a single output signal, each of said P input ports accepting non-overlapping interleaved sets of N/P wavelengths; and an optical coupler that combines said signal output signal with said WDM signal.