A new improved-performance decoding technique for Asymmetrically-Clipped Optical-OFDM

In this work, an improved receiving technique for Optical Wireless Intensity Modulation and Direct Detection (OW IM-DD) communication system, with Asymmetrically-Clipped Optical OFDM (ACO-OFDM) modulations, is proposed. The (socalled in the literature) “clipping noise”, which carries 50% of the transmitted signal power is customarily discarded. Instead we show that the clipping noise carries information related to the original unclipped signal. Hence it is used in the proposed receiver scheme to generate an improved estimator for the transmitted signal. It is shown both theoretically and numerically, that the new approach improves the receiver performance of the system by up to 3dB without a change to the modulated signal.