TR-clipping algorithm for PAPR reduction in O-OFDM system

There exists high peak to average power ratio (PAPR) in optical orthogonal frequency division multiplexing (O-OFDM) system. Traditional tone reservation (TR) method is improved to be adapted to current O-OFDM system. A new method combining of improved TR and clipping is proposed to reduce the influence of clipping noise and decrease the PAPR of OFDM signal at the same time. The proposed method is proved to be with low computational complexity and high technical feasibility. The simulation results show that the in-band noise and out-of-band spectrum are restrained effectively with TR-clipping under a reasonable value of threshold and reserved subcarriers number of W. For BER=10^-6, as clipping ratio γ decreases from 7 dB to 2 dB, the needed OSNR is reduced from 0.2 dB to 7 dB compared with the clipping method.