A Modified SLM Scheme for PAPR Reduction in OFDM Systems

Orthogonal frequency division multiplexing (OFDM) is considered as a reliable technique for wireless communications. However, OFDM signals have the high peak-to-average power ratio (PAPR), which causes the deteriorated system performance. Selected mapping (SLM) is regarded as one of the productive schemes for PAPR reduction in OFDM systems, but the high computational complexity limits its application. Thus, a modified SLM (M-SLM) scheme for improving PAPR problem in OFDM systems is proposed. It first uses two orthogonal phase factor sets to generate two groups of original OFDM candidate signals. Then, more candidate signals are obtained by employing the linear combinations of two groups of original candidate signals based on the linear property of IFFT. Simulation results show that the M-SLM scheme has the similar PAPR performance accompanied by the remarkable computational complexity reduction compared with original SLM and the existing GreenOFDM.