Low Peak-to-Average Power Ratio FBMC-OQAM System based on Data Mapping and DFT Precoding

TL;DR

This paper introduces a novel data mapping and DFT precoding scheme for FBMC-OQAM systems that significantly reduces peak-to-average power ratio without the need for OQAM pre-processing, improving spectral efficiency.

Contribution

It proposes a new map-DFT-spread FBMC-OQAM scheme that enhances PAPR reduction and eliminates the OQAM pre-processing step, which is a novel approach in this context.

Findings

The proposed scheme achieves better PAPR reduction than simple DFT spreading.

Numerical simulations show a trade-off between PAPR and out-of-band performance.

The effect of prototype filter design on PAPR is analyzed.

Abstract

Filter bank multicarrier with offset quadrature amplitude modulation (FBMC-OQAM) is an alternative to OFDM for enhanced spectrum flexible usage. To reduce the peak-to-average power ratio (PAPR), DFT spreading is usually adopted in OFDM systems. However, in FBMC-OQAM systems, because the OQAM pre-processing splits the spread data into the real and imaginary parts, the DFT spreading can result in only marginal PAPR reduction. This letter proposes a novel map-DFT-spread FBMC-OQAM scheme. In this scheme, the transmitting data symbols are first mapped with a conjugate symmetry rule and then coded by the DFT. According to this method, the OQAM pre-processing can be avoided. Compared with the simple DFT-spread scheme, the proposed scheme achieves a better PAPR reduction. In addition, the effect of the prototype filter on the PAPR is studied via numerical simulation and a trade-off exists between the PAPR and out-of-band performances.