Cyclic prefix-aided linear trajectory search for phase-noise mitigation in coherent optical-OFDM systems

Estimating and mitigating the phase noise (PHN) in orthogonal frequency-division multiplexing (OFDM) greatly improves the system performance. Recently, a PHN mitigation method using the best match trajectory (BMT) method was proposed, and it outperformed the conventional inter-carrier interference (ICI) compensation methods in both bit error rate and computational complexity. The authors propose a modified version of the BMT method in order to further improve the computational performance when mitigating the PHN in coherent optical OFDM systems. Their simulations show that the proposed linear PHN trajectory achieves better PHN estimation than the conventional PHN trajectory, and the proposed scheme reduces the computational complexity compared with the BMT method.