A Novel Timing Synchronization Method for DCO-OFDM-Based VLC Systems

Being sensitive to synchronization errors, symbol timing synchronization is a key factor affecting the performance of orthogonal frequency division multiplexing (OFDM) -based visible light communication (VLC) systems. A novel timing synchronization method based on odd-even symmetry for direct current biased optical OFDM (DCO-OFDM) is investigated in this paper. The proposed method produces an excellent pulse-like timing metric, resulting in a sharper peak at the correct place, while the values of other parts are negligible. The performance of the proposed timing synchronization approach is assessed by measuring the root mean squared error (RMSE) and mean absolute error (MAE) of timing offset estimation and bit error rate (BER) performance by computer simulation. The simulation results show that this novel symbol timing synchronization approach is superior to the typical methods for DCO-OFDM, such as the Park method and Guerra method, in various channel environments.