Analyzing the benefit of optical transmission systems based on root raised cosine PS-QPSK and a flexible channel grid
Résumé
We numerically investigate the multi-channel transmission performance of Polarization Switched Quadrature Phase Shift Keying (PS-QPSK) and we compare it to the performance of Polarization-Division-Multiplexed QPSK (PDM-QPSK), using Root Raised Cosine (RRC) spectral shaping, in the context of a flexible channel grid. We point out the impact of the roll-off factor and the potential influence of different dispersion management scenarios. Finally, the advantage of PS-QPSK against PDM-QPSK is presented as a function of the system parameters, while we also discuss the benefit of a RRC spectral shaping against a tight filtering at the transmitter side with a Gaussian-shaped filter.