A broadband high-efficiency GaN-based power amplifier using an improved continuous mode

Abstract

This paper proposes a broadband high-efficiency power amplifier using an improved continuous mode design. A tuning parameter is introduced into the current expression of the drain to purposely introduce more sine components. These sine components extend the impedance space of the traditional continuous mode, provide greater flexibility in the design of the broadband output matching network, thereby widening the operating bandwidth. Moreover, since no overlap between the current sine components and the voltage cosine components are produced, these sine components do not degrade the PA’s efficiency, unlike traditional continuous-mode PAs that often trade efficiency for bandwidth. To validate our approach, a broadband high-efficiency power amplifier is designed using GaN HEMT. Measurements indicate that output power is between 40.8 dBm and 42.3 dBm, and the drain efficiency varies from 72.7%–81.8% in 1.5–2.5 GHz, while the gain is between 11.3 dB and 13.0 dB in the same frequency range.