An improved scheme for low complexity of PAPR reduction in OFDM system

Among all techniques for peak-to-average power ratio (PAPR) reduction in orthogonal frequency division multiplexing (OFDM) systems, partial transmit sequence (PTS) scheme provides an effective solution. However, PTS requires an exhaustive searching for finding the best phase weighing factors, causing large amount of computational complexity. In this paper, an improved scheme for PTS is proposed, focusing on phase weighing factors be divided into several grades. In addition, a novel method of combining grading PTS and companding technique with linear lincompex is proposed for further PAPR reduction. Simulation results show that grading PTS is an efficient way for reducing computational complexity, but with no performance improved. The combined scheme shows a further reduction for PAPR with the scarification of bit error rate (BER). For the systems which may bear relatively high bits error such as voice signals, this scheme may well reduce system PAPR.