Differential multi-feedback scheme for a fast adapting polarization stabilizer

A planar lightwave polarization stabilizer concept has been proposed which is based on a multi-feedback scheme providing individual and bipolar feedback signals for each of the phase shifters of the integrated optic waveguide structure. This allows for fast adaptation to changing input state of polarization and simple adaptation control. In part this feedback scheme has experimentally been confirmed by showing no receiver sensitivity degradation after stabilizing an 80 Gb/s RZ signal with changing polarization at the input port of a polarization sensitive OTDM receiver. Extension of the proposed feedback scheme to a planar PMD compensator was discussed by numerical simulation showing that pattern correlation and fast optical gates are required.