Design and Performance Analysis of the SPW Method for PAPR Reduction in OFDM Systems

Abstract

This paper addresses the subblock phase weighting (SPW) method to reduce the peak-to-average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM) system. This method is to divide the input block of OFDM signal into many subblocks and lower the peak power by weighting the phase of each subblocks properly. Also, it is applicable for all kinds of OFDM system regardless of the modulation types and the number of subcarriers. Unlike the PTS (partial transmit sequence) and SLM (selective mapping) method using many IFFTs, the SPW method can be realized by only one IFFT. In this paper, the PAPR reduction performance is novelly examined when the adjacent, interleaved and random subblock partitioning schemes are used in the SPW system. The random subblock partition scheme has the most effective performance among the three schemes. In the SPW system, more subblocks can effectively reduce the PAPR but there is a problem that the processing time of iteration is increased. To solve this problem, we propose a new weighting factor combination of the complementary sequence characteristic with threshold technique. OFDM data can be correctly recovered at receiver by the inserted side information of weighting factor in the feed forward type. Also, BER performance of this SPW system is analyzed when error happens in the side information.