Symbol timing synchronization algorithm for 112Gbit/s PDM CO-OFDM systems

We propose a modified symbol timing synchronization algorithm for polarization division multiplexed (PDM) coherent optical orthogonal frequency division multiplexing (CO-OFDM) systems. This method can significantly reduce the impacts of the platform phenomenon and the chromatic dispersion, when it is compared with the typical Schmidl&Cox algorithm. Simulation results with the compare between the typical algorithm and proposed method show that the latter has much better performance in optical fiber channel. 1-dB signal quality improvement is achieved for PDM CO-OFDM system at 112Gbit/s data rate over 500-km SSMF without dispersion compensation.