Nonlinear mitigation on subcarrier-multiplexed PM-16QAM optical systems

• Published in: Optics express Vol. 25; no. 4; pp. 4298 - 4311
• Main Authors: Guiomar, F P, Carena, A, Bosco, G, Bertignono, L, Nespola, A, Poggiolini, P
• Format: Journal Article
• Language: English
• Published: United States 20-02-2017
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/OE.25.004298

We report a comprehensive set of experimental, simulation and analytical results on the benefit of nonlinear mitigation strategies for multi-subcarrier (MSC) PM-16QAM transmission systems. First, we demonstrate ~9% maximum reach gain enabled by symbol-rate optimization (SRO) of MSC-PM-16QAM in a 31 channels WDM transmission experiment. Then, we demonstrate that, in the considered experimental scenario, the gain provided by digital backpropagation (DBP) over single-carrier (SC) transmission is similar to that achieved by SRO over MSC transmission. Furthermore, we show that the SRO phenomenon can be weakened after self-channel interference (SCI) removal through DBP. As a result, and due to DBP performance limitations in the experiment, the combined effect of SRO and DBP was found to enable only an additional 4% gain in maximum reach. Finally, we address the impact and symbol-rate dependence of nonlinear phase noise (NLPN) in MSC-PM-16QAM transmission, discussing on the NLPN mitigation capability of standard carrier phase estimation (CPE) and on respective gains that could be achieved through its enhanced mitigation.