Abstract:

Based on selected mapping (SLM) for peaktoaverage power ratio (PAPR) reduction in OFDM system, an improved version, named adaptive multistage selected mapping (AMSLM) is proposed. By using different phase weighting factor set and selected mapping in each stage, the property of correlation of candidate vectors in  different stages is reduced, which improves the PAPR performance. Moreover, with the purpose of reducing the computational complexity, a proper threshold is introduced, where if the minimum value of PAPR obtained in current stage is higher than the threshold, the optimization process for next stage will continue; otherwise, the whole optimization process will be terminated. Simulation results show that, compared with SLM, proposed AMSLM scheme has almost the same or better performance in PAPR reduction. Meanwhile, the computational complexity is reduced dramatically, where AMSLM with four stages outperforms SLM by 4781％ in computational complexity.

Key words: orthogonal frequency division multiplexing; peaktoaverage power ratio; selected mapping