An Effective SLM-PRSC Hybrid Scheme for OFDM PAPR Reduction Based on Repeated Utilization of Identical PRSC Sequences in Time Domain

Abstract

In order to improve OFDM (Orthogonal Frequency Division Multiplexing) PAPR (Peak-to-Average Power Ratio) reduction performance of the conventional SLM (SeLective Mapping) method, we propose two effective SLM-PRSC (PAPR Reduction Sub-Carrier) hybrid schemes based on repeated utilization of the identical PRSC sequences in the time domain. In the proposed schemes, after performing the SLM for the frequency domain OFDM symbol excluding pre-determined PRSC positions, the final SLM-PRSC hybrid sequence with the lowest PAPR, which is generated by adding the time domain PRSC sequence to the results of the SLM, is selected as the transmitted OFDM signal. Since the identical PRSC sequences generated a priori are repeatedly used for every OFDM symbol, excessive IFFT (Inverse Fast Fourier Transform) calculations are avoided. Moreover, the selected PRSC symbols in the frequency domain may be utilized as an overhead information for the SLM. Simulation results reveal that the proposed schemes can significantly improve the PAPR reduction performance of the conventional SLM, while avoiding excessive increase of IFFT calculations and the overhead for the SLM.