Harmonic-based model for bandpass nonlinearity and its application to RF predistorter design

Paper in proceeding, 2003

Due to their large bandwidth of operation, RF predistorters are suitable for linearizing amplifier nonlinearity in high speed wireless applications. Unlike baseband linearization techniques, RF predistorters generate overtones which contribute to the first zone output of the bandpass high power amplifier. This paper presents a model for a bandpass nonlinearity that is based on measurements on several harmonics of the output. The model matches different harmonics of the output signal fairly well. The model is then used to design an RF predistorter. The advantage of the method compared to a design based on first zone of the output, is that the predistorter minimizes the total distortion power instead of reducing one specific intermodulation product.