OFDM based fiber nonlinear impairment compensation for long-reach passive optical networks

Orthogonal frequency division multiplexing (OFDM) is an extensive technology in commercial communication because of its ability to mitigate channel distortions. OFDM technique achieves high spectral efficiency and requires simple channel equalization. It has received significant interest to photonics community as an attractive solution for long-reach transmission, as it offers a reduced signal bandwidth and enables simple digital equalization. This paper investigates the performance of optical OFDM (OOFDM) system using fiber nonlinear effects. A new approach named impairment factor is introduced to reduce the fiber nonlinear impairments of the system. The simulation results have been provided for dual polarization OOFDM system with multi-level quadrature amplitude modulation (M-QAM) applied to the optical signal subcarriers. The performance of the proposed OOFDM system is compared to the conventional single carrier optical system with M-QAM for the same number of information bits.