Efficiency enhancement of a WiMAX switching mode GaN power amplifier through layout optimization of distributed harmonic matching networks

This work proposes a method to enhance the efficiency of a WiMAX switching mode GaN power amplifier through the layout optimization of harmonic matching networks. In the first step, the optimal termination conditions for the inverse class F power amplifier are extracted through load-pull measurement. Afterward, the loss in the multiharmonic output matching network is minimized through layout optimization in order to improve the efficiency of the PA. The fabrication of an inverse class F for WiMAX applications following the optimization procedure demonstrates that the power added efficiency is improved by 5% when minimizing the loss in the output matching network compared to a nonoptimized circuit. The fabricated PA power added efficiency reaches 71.2% after loss minimization.