Enhanced DC-biased optical OFDM for intensity-modulated optical OFDM access systems

In this paper, an enhanced DC-biased optical orthogonal frequency division multiplexing (EDCO-OFDM), compatible with intensity-modulation optical access systems is proposed. Compared to conventional dc-biased optical OFDM (DCO-OFDM), EDCO-OFDM overcomes the performance limitation pertinent to high peak-to-average power ratio (PAPR) and provides better power and spectral efficiency over the state-of-the-art DCO-OFDM at the expense of increased computational complexity. High PAPR of the optical OFDM signal is counteracted using clipping and the clipping distortion instigated due to the clipping process, is mitigated at the receiver by reconstructing the affected samples iteratively. The fundamental parameters such as bit-error rate (BER) performance, spectral efficiency, and complexity, are analysed for EDCO-OFDM and compared with DCO-OFDM. Simulation results are provided to demonstrate the superiority of EDCO-OFDM over conventional DCO-OFDM.