Null subcarrier assisted selective mapping for PAPR reduction in OFDM systems without side information

In this paper, a novel selective mapping (SLM) scheme, assisted by null subcarriers, is proposed to reduce the peak-to-average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) signals without side information (SI). The main idea of the proposed method is to employ the locations of a small percentage of null subcarriers to indicate the indexes of the phase sequences in the SLM method. At the receiver, energy detection is adopted to find out the positions of null subcarriers, from which the SI (the index of the optimal phase sequence) can be recovered. Both theoretical analysis and simulation results prove that the proposed method can get robust SI detection in good channel conditions.