Diversity combining via symmetry recovering for asymmetrically clipped optical OFDM

A new diversity combining receiver is proposed for asymmetrically clipped optical orthogonal frequency division multiplexing (ACO-OFDM). With the aid of symmetry recovering the odd and even signals of ACO-OFDM are distinguished directly in time domain without complex operation such as inverse fast Fourier transform (IFFT). Simulation results show that the diversity combining receiver we proposed gives a signal-to-noise ratio (SNR) improvement of 2∼3 dB. The receiver proposed also has the same SNR gain as the conventional diversity combining receiver distinguishing the odd and even signals in frequency domain.