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Orthogonal frequency-division multiplexing technique (OFDM) has been adopted widely as a modulation technique for radio frequency (RF) and optical communication systems such as visible-light communication (VLC) due to its high spectral efficiency and low-complexity implementation. VLC-OFDM is recommended in 5 G mobile communication. However, VLC-OFDM suffer from the high peak to-average power ratio (PAPR). In this paper, a modified selective mapping (MSLM) method is applied to the proposed system followed by a new envelope scaling process for further reductions in PAPR of VLC-OFDM system. Simulation results show that the proposed method reduces the PAPR by about 6.8 and 1.7 dB comparing with the original signal and the traditional SLM with a number of rotation vector U = 8, respectively.

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A performance evaluation of selective mapping localised single carrier frequency division multiple access technique (SLM LSC-FDMA) is presented over channel measured at 30 GHz. These measurements were taken between three buildings under non-line-of-sight (NLOS) for a propagation path length of 183 m. Simulation results present a peak-to-average power ratio gain of 3.78 dB for the proposed scheme over localised orthogonal frequency division multiple access system and an acceptable bit error rate with and without high power amplifier compared with LSC-FDMA. These results show an improvement of the transmission efficiency under NLOS outdoor scenario at 30 GHz. Hence, these results suggest the use of SLM LSC-FDMA wave form for fifth generation mobile communication at 30 GHz.