A new analytical method for analysis and design of class E power amplifiers taking into account the switching device on resistance

The new analytical method presented in this paper extends the principle of the equivalent small parameter method (ESP, an improved perturbation technique) to analyse and design Class E power amplifiers. Using this method the analytical expression for the output voltage (or current), containing the fundamental frequency component, the second, third and other higher harmonics, can be obtained. Based on this analytical expression, the other analytical expressions which represent the performance of Class E power amplifiers, such as collector-emitter voltage and collector current of the switching transistor, the efficiency, the output power as well as the power-output capability can also be obtained. This method is applicable to analyse Class E power amplifiers with any circuit configuration and parameters at any switching-on duty cycle, and does also take into account the switching transistor ON resistance. It is valuable to the design of Class E amplifiers by offering designers insight into circuit behavior. Copyright (C) 1999 John Wiley & Sons, Ltd.