The Doherty Power Amplifier: Design strategy

This paper shows a proposal of methodology for designing Doherty Power Amplifiers (DPAs) with arbitrary output-back-off (OBO), main and peak devices. As a demonstration, a 7.5dB OBO DPA has been designed, using two devices from Cree Inc, and simulated in Advanced Design System 2014. The amplifier uses the GaN-HEMT CGH40006 and CGH40010 devices, for main and peak branches, respectively. On the Doherty region, an output power of 25.1W has been obtained together with a gain higher than 15dB, whereas the obtained added efficiency has been demonstrated to be between 57 and 63%