Analytical Design Equations for Class-E Power Amplifiers

This paper presents the analytical solution in time domain for the ideal single-ended class-E power amplifier (PA). Based on the analytical solution a coherent noniterative procedure for choosing the circuit parameters is presented for class-E PA's with arbitrary duty-cycle and finite dc-feed inductance (e.g., continuously ranging from class-E with small finite drain inductance to class-E with RF choke). The obtained analysis results link all known class-E PA design equations as well as presenting new design equations. The result of the analysis gives more degrees of freedom to designers in their design and optimization by further expanding the design space of class-E PA.

I. Introduction

The Class-E concept has been introduced by Ewing [1] in his doctoral thesis in 1964. Since then many papers analyzing Class-E power amplifier have been published [2]–[24] and many different aspects of Class-E power amplifier (PA) have been analyzed. The published papers can be categorized in two main groups: Class-E PA with RF choke [1]–[11] and Class-E PA with finite dc feed inductor [12]–[24].