Fiber Nonlinearity Mitigation in Long-Haul Coherent Optical OFDM

This paper analyses the phase noise of Coherent optical OFDM (CO-OFDM) system inducing by chromatic dispersion (CD), fiber nonlinearity and amplified spontaneous-emission (ASE) noise. Zero interpolated in OFDM symbol could improve the transmission performance without requiring additional optical components, because the impact of system nonlinearity could be moderated. Simulation shows that a 2-dBm increase in launch optical power is possible and the system Q can be substantially improved more than 2 dB for a long haul CO-OFDM systems.