Low-Complexity Time Domain PAPR Mitigation by Amplitude Modification for OFDM Systems

High peak to average power ratio (PAPR) is a particular disadvantage of orthogonal frequency division multiplexing (OFDM) systems and can significantly degrade the power efficiency at the transmitter. Selective mapping (SLM) is one of the most promising PAPR reduction techniques but invoks multiple IFFT processes thus increase the system complexity, latencies and incur high power consumption. The aim of this paper is to propose a novel post-IFFT PAPR reduction scheme combined with a intelligent strategy for generating a unique timedomain sequence per OFDM block to minimize the PAPR. The impact of the proposed method on the system's bit error rate (BER) performance will also be investigated. It will be shown that our proposed technique has better overall PAPR reduction ability than the ordinary SLM while at the same time requires several order of magnitude less complexity than that of the SLM technique.