The PAPR reduction techniques based on WPT for CO-OFDM systems

In coherent optical orthogonal frequency division multiplexing (CO-OFDM) systems, the high peak to average power ratio (PAPR) will causes serious signal degradation through the nonlinearity of modulator and fiber. In this paper, the PAPR reduction techniques based on wavelet packet transform (WPT) for CO-OFDM systems are proposed, the WPT is used instead of traditional fast Fourier transform (FFT). Moreover, two efficient PAPR reduction techniques are combined with the proposed WPT-OFDM. Simulation results show that the PAPR of proposed scheme combined with selective mapping (SLM) and partial transmit sequence in combination with clipping (clipping PTS) are optimized compared to the traditional FFT. Under the same conditions, while maintaining good performance in the BER compared to ordinary FFT. And the proposed WPT system provides the high spectral efficiency transmission without CP.