A 6–18GHz GaN Distributed Power Amplifier Using Reactive Matching Technique and Simplified Bias Network

Abstract

Two-stage reactively matched gain cells are applied to design a high-gain multi-octave distributed power amplifier (DPA) in this paper. The proposed reactively matched distributed amplifier (RMDA) structure shows a high gain and high output power performance within a small die size. The DC bias network of each section is simplified to implement the proposed structure in an MMIC and the design guide for the bias network is provided. A 6–18 GHz GaN DPA fabricated with the commercial 0.25-μm GaN HEMT process shows output power reaching 40.3–43.9 dBm with 16–27% PAE. To the best of our knowledge, this is the first demonstration of a GaN DPA using reactively matched gain cells, and it exhibits excellent small-signal gain and RF power performance capabilities among other reported GaN PAs with a multi-octave bandwidth up to the Ku-band. Index Terms—broadband amplifier, distributed amplifier (DA), GaN MMIC, multi-octave, power amplifier (PA).