High-Efficiency GaN Doherty Power Amplifier based on Inverse Class-F Operation

This paper presents the design and characterization of a Doherty power amplifier based on high-efficiency continuous inverse class-F individual amplifiers. The prototype achieves a saturated output power in excess of 42.5dBm, with efficiency higher than 70% and 50%, at saturation and 6dB output back-off respectively, over the frequency band 1.45GHz–1.75GHz (18% fractional band). The good agreement between simulations and measurements and the comparison with the state of the art at similar frequencies demonstrate the potential of the application of harmonic tuning strategies to the Doherty architecture, despite the challenge of maintaining wideband operation.