Pulse Operation of an Inverse Class-F GaN Power Amplifier

This paper presents an inverse class-F power amplifier (PA) based on gallium nitride (GaN) high electron mobility transistor (HEMT) at 1 GHz. The implemented PA has a peak power-added-efficiency (PAE) of 74.1%, drain efficiency (DE) of 77.36%, and a gain of 13.76 dB at an output power of 39.58 dBm with a continuous wave operation at 28 volts. We have carried out the experiments with various pulsed operating conditions. A RF performance peak PAE of 74.28% with drain efficiency of 77.57% and a gain of 13.73 dB, at an output power of 39.66 dBm, was obtained at a pulse width of 100 mus with a duty of 10%. To evaluate the linearity of the inverse class-F amplifier, two-tone measurements have been tested. At a tone spacing of 100 kHz, the measured third-order intermodulation distortion (IMD3) was 13.2 dBc at peak PAE.