Design of a high-efficiency dual-band harmonic-tuned power amplifier via simplified real frequency technique

The design of a highly efficient dual-band power amplifier operating at 2.1 GHz and 2.6 GHz is presented in this paper. The output matching network is constituted with two parts, one is used to control the harmonic impedance, and the other is to match the 50 Ω load to the targeted fundamental impedance at this two frequencies. The harmonic controlled network is implemented with short-circuited and open-circuited transmission lines, and the fundamental matching network is synthesized by the simplified real frequency technique. A packaged 10 W GaN transistor is used to design a power amplifier to verify the design method. Measured results show that the realized power amplifier achieved 11.05 dB gain, 42.05 dBm output power at 2.1 GHz, and 12.5 dB gain, 40.5 dBm output power at 2.6 GHz, with the maximum drain efficiencies of 70.7% and 70.3% respectively.