High efficiency class-E switched mode power amplifier design and optimization with random search algorithm

The class E switched mode power amplifier consists of a load network and a single transistor that is operated as a switch at the carrier frequency of the output signal. Main three parts of the power amplifier that specify its total efficiency are: the Q factor of output band-pass filter, the transistor on-state resistance, and the driver stage. In this paper, we design and optimize three common structures of power amplifiers using a random search algorithm. Optimized designs are simulated with HSPICE in 0.25 /spl mu/m CMOS technology at the carrier frequency of 5.2 GHz. The maximum efficiency for each structure is calculated, and then its bottle-neck is determined. We also achieve the total efficiency of 92.3% for the power amplifier.