High efficiency push-pull inverse class F power amplifier using a balun and harmonic trap waveform shaping network

We present the design and development of a push-pull inverse class F power amplifier in X band using a novel harmonic matching network. The harmonic matching network is realized by a simple, low-loss, Marchand balun and a harmonic trap circuit. This novel harmonic matching network not only provides 3-dB power combining, but also enables waveform shaping for enhanced efficiency. This 1-stage power amplifier using discrete GaAs pHEMTs achieves a measured saturated output power of 33 dBm with a power added efficiency of 63% and a gain of 10 dB. This amplifier operates at 10 GHz with a 6% fractional bandwidth.