Adaptive Polarization Modulation in Depolarization Channel with Polarization Dependent Loss

To adapt to variation of polarization dependent loss (PDL) in depolarization channel, an adaptive polarization modulation scheme which can improve the spectral efficiency of polarization modulation system is proposed. In the proposed scheme, the transmitter adapts the optimal constellation size to the variation of the channel due to PDL while fulfilling a fixed target BER constraint, which is based on the received feedback information of channel state information estimated at the receiver. Our simulation results and analysis show that, adaptive polarization modulation (APM) can achieve higher spectral efficiency (SE) than nonadaptive polarization modulation, subject to the same fixed target BER constraint.