Double-Optimal PTS Scheme for PAPR Reduction in OFDM Systems

In this paper, a double-optimal partial transmit sequence (DO-PTS) for orthogonal frequency division multiplexing (OFDM) is proposed. Through twice optimization for subblocks, additional phase factors can be indirectly involved, which increases the diversity of phase rotations. In the first optimization, optimized subblocks are generated by grouping and intra group weighting, and some OFDM candidate signals can be achieved by combined these optimized subblocks. In a second time of optimization, by further optimizing optimized subblocks, the subcandidate signals are generated to produce more OFDM candidate signals. Moreover, in order to reduce computational complexity, the relationship between candidate signals is used for simplifying the process of generating candidate signals. Simulation results show that compared with original PTS (O-PTS), this proposed scheme not only achieves the same PAPR performance, but also reduces computational complexity immensely.

I. Introduction

Orthogonal frequency division multiplexing (OFDM) technology is used extensively in high-speed data communications because of its excellent performance, such as high frequency spectrum utilization, anti-multipath delay, anti-frequency selective fading and so on. And OFDM has been adopted in wireless communication standards such as Digital Video Broadcasting (DVB) and mobile worldwide interoperability for microwave access (WiMAX) [1].