OPTICAL CROSS-CONNECTOR CONTAINING A MULTI-STAGE CLOS NETWORK IN WHICH A SINGLE-STAGE MATRIX COMPRISES ONE STAGE OF THE CLOS NETWORK

摘要

A wavelength division multiplex (WDM) optical cross-connect (OXC) has aplurality (N x M) of input and output channels (iI to iM; 01 to oM) forthrough traffic. A first group of optical switching matrices (SI-I to SI-N) isprovided for connecting the through traffic input channels (iI to iM) to theoutput channels (01 to oM), wherein each through traffic input channel (iI toiM) is connected to an input of a switching matrix (SI-I to SI-N) of the firstgroup and each through traffic (01 to oM) is connected to an output of theswitching matrix (S1-1 to S1-N). Additionally a plurality (P) of inputchannels (a1 to aP) and/or output channels (01 to oP) is provided foradding/dropping traffic. Each add/drop input/output channel (a1 to aP, o1 tooP) is connected to an input/output of a second group of switching matrices(S2~ -1 to S2~ -AD). The outputs/inputs of the second group of switchingmatrices are connected to inputs of a third group of switching matrices (S3-1to S3-2M-1) or outputs of a fourth group of switching matrices (S4-1 to S4-(2M-1)) and the outputs/inputs of the third/fourth group of switching matrices areconnected to inputs/outputs of the first group of switching matrices such thatthe switching matrices or the second, third and first groups of the first,fourth and second groups each form a Clos network.