A new method for fiber nonlinearity mitigation for long-haul Coherent Optical OFDM system

a new technique for using clipped OFDM signal in long-haul Coherent Optical OFDM system (Clipped CO-OFDM) to mitigate fiber nonlinear effects is presented. Clipped OFDM is generated by clipping conventional CO-OFDM signal at zero and selects the odd subcarriers to carry data. The merits are that not only cross talk due to fiber nonlinearity are reduced, but also Clipped CO-OFDM reduces the PAPR and the wanted signal carried on odd subcarriers is orthogonal to clipping noise which fall on even frequencies. With such a scheme, simulation demonstrates that Clipped CO-OFDM is to be able to increase the nonlinear threshold and system Q value is substantially improved more than 2dB at a reach of 960km. Clipped CO-OFDM could to be a simple and effective solution to mitigation fiber nonlinearity in long-haul CO-OFDM system.