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 multi-harmonic 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 non-optimized circuit. The fabricated PA power added efficiency reaches 71.2% after loss minimization.