Extensive simulation of fibre non‐linearity mitigation in a CO‐OFDM‐WDM long‐haul communication system

Abstract

In this study, a performance comparison of fibre non-linearity mitigation is performed in the context of 10 and 20 Gb/s coherent optical orthogonal frequency-division multiplexing and wavelength division multiplexing (CO-OFDM-WDM). The authors compare two regression methods based on the third-order Volterra series and least mean square algorithm in terms of the bit error rate (BER) for different transmission distances and modulation formats. They also evaluate the BER as a function of the number of OFDM subcarriers for the Volterra-based non-linear equaliser (VNLE). In addition, by increasing the order of the VNLE from third-order to fifth-order series, a significant increase of performance is obtained for 100 Gb/s CO-OFDM-WDM system. Likewise, a comparison study of 16-QAM 40 Gb/s CO-OFDM system is performed as a function of Q-factor for support vector machine, Volterra equaliser and linear equaliser, respectively.