A systematic method to design high efficiency harmonic tuned power amplifier with PAE over 80%

This paper presents the design, implementation and measurement results of a high efficiency harmonic tuned PA at 2.85GHz using a high power GaN HEMT transistor. Based on large signal equivalent circuit model and computer-aided design tools, optimum fundamental and harmonic impedances are obtained to maximize PAE. The compromise between PAE and complexity along with proper selection of matching circuit topology simplify design and adjustment procedure, and also reduce the dimension of circuit. With the stimulus of continuous wave, the measurement results show a maximum power-added efficiency of 82.2%, a maximum drain efficiency of 86.6%, a power gain of 12.91dB with 39.91dBm output power.