Y. Sun et al., Study of system performance in a 107-km dispersion-managed recirculating loop due to polarization effects, IEEE PHOTON, 13(9), 2001, pp. 966-968
We investigate the polarization evolution for both signal and noise in two
107-km recirculating loops with polarization-dependent loss per round-trip
of 0.35 dB and less than 0.1 dB, respectively. When the system is optimized
, in the first case, both signal and noise are polarized, while in the seco
nd case, the signal tends to depolarize due to the noise. We experimentally
measured and theoretically simulated the Q factor distribution, which is f
ar from what is expected for straight-line systems, after 5000 km in the se
cond case. We also suggest a simple method for obtaining the same Q distrib
ution in recirculating loop experiments as expected in straight-line experi
ments.