Patent ID: 8200087

Claim:
A method for stabilizing the state of polarization of polarization multiplexed optical radiation, said polarization multiplexed optical radiation comprising an identified channel which is provided with a pilot signal, comprising: (a) providing to the polarization multiplexed optical radiation a first controllable polarization transformation to generate a first transformed optical radiation; (b) detecting a first state of polarization of a first polarized portion of the identified channel of the first transformed optical radiation with respect to a first polarization parameter of the first transformed optical radiation; (c) controlling, responsively to said first state of polarization, the first controllable polarization transformation so that the first polarization parameter of the first transformed optical radiation has a predetermined value independent of a polarization state of the polarization multiplexed optical radiation; (d) providing to the first transformed optical radiation a second controllable polarization transformation to generate a second transformed optical radiation; (e) detecting a second state of polarization of a second polarized portion of the identified channel of the second transformed optical radiation; and (f) controlling, responsively to said second state of polarization, the second controllable polarization transformation so that the second state of polarization has a predefined value.