Comparison of four OFDM signal representations approaches for high dynamic range nonlinear PA behavioural modelling

Abstract

This paper presents advances in techniques for representing OFDM signals in nonlinear RF power amplifier behavioural modelling. OFDM is significantly sensitive to nonlinear distortion because of the high peak to average power ratio (PAPR) of its envelope. Four signal representation techniques are presented and compared. These are direct time domain method (DTD), mixed frequency and time domain method (MFTD), statistical approach (stat), and MFTD combined with a modified stat approach (MFTD-MS). AH four are applied to a Bessel Fourier behavioural model for a GaN nonlinear PA. This model is a particularly suitable tool for large dynamic range nonlinearity analysis of certain classes of multicarrier signals. The goal is to compare accuracy, preservation of modulation information, complexity and computer resource consumption.