A Low Complexity SLM-Based Radix FFT Method for PAPR Reduction in OFDM Systems

A low complexity selective mapping (SLM) technique for reducing the peak-to-average power ratio (PAPR) of an orthogonal frequency division multiplexing (OFDM) signal is introduced. The intermediate signals within an N-point IFFT are used to generate the phase sequences. We use decimation in frequency (DIF) and propose a low computational complexity technique based on multiplying the phase sequences at different IFFT stages. This new technique greatly reduces the multiplicative complexity while providing similar PAPR reduction to ordinary SLM (O-SLM). The additive complexity is also reduced.