Patent ID: 7280764

Claim:
A method of transferring a plurality (I) of independent optical signals {S i } through an optical channel having two ends, the method comprising the steps of: (a) generating a plurality of (I) independent pseudorandom bit sequences (PRBSs); (b) modulating a preselected optical mode of the i th independent optical signal S i according to the i th independent pseudorandom bit sequence PRBS i to form an i th modulated optical signal MS i , where i={1, . . . I}; (c) combining a plurality (I) of the modulated optical signals {MSi} to form an optical multiplex signal; (d) transmitting the optical multiplex signal through the optical channel from one end to the other end; (e) modulating the preselected optical mode of the optical multiplex signal according to the i th pseudorandom bit sequence PRBS i to form an i th modulated multiplex signal MMS i ; and (f) passing the i th modulated multiplex signal MMS i through a mode filter, whereby the independent optical signal S i is recovered.