A Comparison Between Single and Differential-Ended Doherty Power Stages in GaN Technology for 28-GHz 5G Applications

This paper presents a comparison between single-ended and differential-ended output stages for a Doherty power amplifier for 28-GHz 5G applications in a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.15\ μ m</tex> Gallium Nitride HEMT technology. The single-ended Doherty power stage achieves 33.6 dBm of saturated output power, a maximum gain of 8.4 dB, and a power added efficiency of 40.5% and 33% at saturation and 6-dB power back-off, respectively. In comparison, the differential-ended Doherty power stage exhibits a saturated power of 36 dBm, a maximum gain of 8.6 dB, and a power added efficiency of 35.3% and 27.7% at saturation and 6-dB power back-off, respectively.