Localised discrete Fourier transform-spread M-ary amplitude shift keying orthogonal frequency division multiplexing with Hermitian symmetry for peak-toaverage power ratio reduction

The authors propose a novel localised discrete Fourier transform (DFT) spread M-ary amplitude shift keying (M-ASK) orthogonal frequency division multiplexing (OFDM) system with the Hermitian symmetry (DFT-spread M-ASK HS OFDM) to reduce the peak-to-average power ratio (PAPR). Compared with the conventional OFDM and localised DFT-spread OFDM, the proposed system has lower PAPR not only because of the DFT-spread scheme but also its lower modulation order than other OFDM systems. The lower modulation order of the proposed system can be achieved by using the Hermitian symmetry of DFT. The simulation result shows that the localised DFT-spread M-ASK HS OFDM provides a significant improvement in bit-error-rate and reduced PAPR.