Orthogonal Basis Expansion-Based Phase Noise Suppression for PDM CO-OFDM System

In this letter, we develop an orthogonal basis expansion (OBE)-based phase noise suppression method for polarization-division-multiplexed (PDM) coherent optical orthogonal frequency-division-multiplexing (CO-OFDM) systems. Compared with the conventional phase noise suppression approach, the OBE method not only significantly promotes the system tolerance of laser phase noise, but also improves the system robustness against nonlinear phase noise. The theoretical analysis is validated by numerical simulations of PDM CO-OFDM systems with 16-quadrature-amplitude-modulation format.