Swapped SLM scheme for reducing PAPR of OFDM systems

The selected mapping (SLM) scheme is a competent method for reducing the high peak-to-average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) signals. One drawback of the conventional SLM (C-SLM) scheme is the high computational complexity. To reduce the complexity of C-SLM, the real and imaginary parts of the OFDM signals are treated separately. The even and odd sequences of the real and imaginary parts are obtained using the Fourier transform properties. More candidates are generated by the different combination of all the sub-sequences. The proposed scheme has a lower computational complexity using only M inverse fast Fourier transform (IFFT) operations to generate M⁴ candidates. The simulation results show that the proposed scheme achieves good PAPR reduction performance and also reduces the computational complexity significantly compared with the C-SLM scheme.