  Self-homodyne systems with polarization multiplexed carrier offer an LO-less
coherent receiver with simplified signal processing requirement that can be a
good candidate for high-speed short-reach data center interconnects. The
practical implementation of these systems is limited by the requirement of
polarization control at the receiver end for separating the carrier and the
modulated signal. In this paper, effect of polarization impairments in
polarization diversity based systems is studied and modeled. A novel and
practical adaptive polarization control technique based on optical power
feedback from one polarization is proposed for polarization multiplexed carrier
based systems and verified through simulation results. The application of the
proposed concept is experimentally demonstrated also for a QPSK system with
polarization multiplexed carrier.
