DFT-spread combined with PTS method to reduce the PAPR in VLC-OFDM system

The high peak to average power ratio (PAPR) was one of the main factors affecting the performance in visible light communication (VLC) system, which was based on the orthogonal frequency division multiplexing (OFDM) technology. This paper analyses the PAPR probability distribution of the OFDM signal in VLC system. In order to reduce the OFDM signal PAPR in VLC system, the Partial Transmit Sequence (PTS) method was modified, which was suitable for transmission in VLC system, and was combined with Discrete fourier transform spread (DFTS) to further reduce the optical OFDM signal PAPR. The simulation results show that, the PAPR of the system is reduced about 3.5dB, 2.7dB, 1.2dB comparing with the original signal, DFTS or PTS method used alone. With increase of system complexity, the method with DFTS combined with PTS has a better PAPR suppression performance.