New PTS Schemes for PAPR Reduction of OFDM Signals Without Side Information

In this paper, two partial transmit sequence (PTS) schemes without side information (SI) are proposed for reducing peak-to-average power ratio of orthogonal frequency division multiplexing signals. The proposed schemes do not transmit SI identifying a rotating vector because identifiable phase offset is applied to the elements of each rotating vector. To extract SI from the received signal and recover the data sequence, the maximum likelihood (ML) detector is used. This ML detector exploits the Euclidean distance between the given signal constellation and the signal constellation rotated by the phase offset. By doing pairwise error probability (PEP) analysis, it is investigated how to choose good phase offsets for embedding SI. Also, the performance degradation caused by SI detection failure is analyzed based on PEP. Finally, through numerical analysis, it is shown that the BER performance of the proposed PTS schemes is not degraded compared with the conventional PTS with perfect SI.

I. Introduction

Orthogonal frequency division multiplexing (OFDM) has been adopted as a standard method in various wireless communication systems because it can achieve high-rate data transmission and insure high reliability over the multipath fading environment [1]. However, high peak-to-average power ratio (PAPR) is a critical drawback of OFDM because OFDM signals are generated by summing a large number of independently modulated subcarriers. High PAPR causes significant inter-modulation and out-of-band radiation when OFDM signals pass through nonlinear devices such as high power amplifier (HPA).