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Low-Complexity Phase Noise Compensation Approach for CO-OFDM Systems

In this letter, a novel low-complexity phase noise (PN) compensation approach is proposed for coherent optical orthogonal frequency division multiplexing systems. By employing Radio Frequency pilot (RFP), the PN is estimated and compensated in the frequency domain (FD), which is free of the penalty induced by nonideal low-pass filters in the conventional RP-pilot method. In addition, the computational complexity is greatly reduced due to the elimination of the narrow-band filter and the simplification of PN compensation in the frequency domain. The numerical simulation exhibits the superiority of the proposed FD-RFP in terms of performance and computational complexity.