PAPR Reduction in OFDM-IM Using Dither Signal Sets

Similar to most multicarrier modulations, orthog-onal frequency division multiplexing with index modulation (OFDM-IM) also suffers high peak to average power ratio (PAPR) issue due to its inherit structure. In this paper, a novel PAPR reduction scheme for OFDM-IM with dither signals is proposed. Unlike the previous method that utilizes convex programming to determine the optimized signals that are added to the idle subcarriers of OFDM-IM. The proposed scheme utilizes several fixed sets which contain constraint amplitude dither signals to reduce the PAPR. Simulation results show that the proposed scheme can achieve solid PAPR reduction performance similar to that of the classical PAPR reduction schemes (e.g. partial transmit sequence (PTS), selected mapping (SLM)). Moreover, compared with the conventional PAPR reduction scheme with dither signals, the proposed one does not need convex optimization, which owns high computational complexity. Also, by utilizing selected dither signals, the proposed scheme can achieve lower error performance than that of the conventional scheme with dither signal.