Shaping code in conjunction with DCT for PAPR reduction in multicarrier system

Younes Aimer,Smail Bachir,Claude Duvanaud,Boubakar Seddik Bouazza

doi:10.1186/s13638-021-01928-0

Abstract

Nonlinear behavior and power efficiency of the Power Amplifier (PA) contradictorily depend on the input signal amplitude distribution. The transmitted signal in multi-carrier modulation exhibits high Peak-to-Average Power Ratio (PAPR) and large bandwidths, leading to the degradation of the radio link and additional generation out-of-band interferences, which degrade the quality of the transmission. Practical solutions exist, like a power back-off, but with unacceptable efficiency performances of the transmitter. This paper deals with efficiency and linearity improvement using a new PAPR reduction method based on the combination of Discrete Cosine Transform and shaping technique. The main principle is to determine an optimal coding scheme according to a trade-off between coding complexity and performance benefits in the presence of PA nonlinearities. Simulation and experimental results in the context of OFDM signal and using a 20 W–3.7 GHz Radio-Frequency Power Amplifier show an improvement on PAPR reduction of about 3.25 dB. Also, the communication criteria like Bit Error Rate and Error Vector Magnitude are improved by about one decade and a half and 8%, respectively.

Highlights

Orthogonal Frequency Division Multiplex (OFDM) is widely adopted in wireless communications to satisfy user requirements like high data rates, security, and mobility
For each OFDM symbol, we evaluate the Peak-to-Average Power Ratio (PAPR) in the case of the original signal, Discrete Cosine Transform (DCT) only and the proposed method combining shaping technique and DCT
3.2.1 Experimental results To evaluate the effectiveness of the proposed method, we show in Figs. 19, 20 the Error Vector Magnitude (EVM) and Bit Error Rate (BER) results with and without the PAPR reduction

Summary

Introduction

Orthogonal Frequency Division Multiplex (OFDM) is widely adopted in wireless communications to satisfy user requirements like high data rates, security, and mobility Among their advantages, we can mention its high spectral efficiency as well as low complexity, implementation flexibility, and robustness against interferences and frequency selective fading [1]. We can mention its high spectral efficiency as well as low complexity, implementation flexibility, and robustness against interferences and frequency selective fading [1] This technique’s major drawback is its high envelope fluctuations defined by the PAPR value [2]. Those techniques can be classified into three classes [26]: coding techniques, adding signal techniques, and probabilistic techniques

Objectives

Results

Conclusion