Load-Pull Analysis of Outphasing Class-E Power Amplifier

Abstract

In this paper, we discuss a load-pull analysis technique to charaterize the efficiency performance of class-E amplifier in an outphasing power combining scheme. Class-E amplifier has the potential to deliver high efficiency. Class-E amplifier is not an ideal current or voltage source as is required for the traditional analysis of outphasing structures. It requires a phase modulated input signal and has a non-linear transfer characteristic which is a function of load impedance. Here we define an operating load locus based on the load-pull analysis which can be used to predict the non-linear transfer function, efficiency, output power, input drive phase and many other factors associated with the outphasing class-E amplifier. This scheme could also be used to characterize any amplifier class in an outphasing structure.