Performance degradation due to polarization effects in a dispersion-managed-soliton recirculating loop system

We investigate the performance degradation in dispersion-managed soliton systems caused by polarization-dependent loss and polarization-mode dispersion using a 600-km recirculating loop. We show that in an ultralong-haul transmission system, polarization effects can easily induce a variation in the bit-error rate (BER) greater than two orders of magnitude. In addition, polarization scattering caused by soliton collisions in wavelength-division-multiplexing systems makes the polarization-induced BER variation smaller than that in single-channel systems.