High Efficiency 2-Stage MMIC GaN Doherty Power Amplifiers with More Than 38% Fractional Bandwidth in C Band

This paper presents and compares two wideband 2-stage inverted Doherty Power Amplifiers (DPAs) covering the entire 4.2-6.2 GHz band, which represents a 38% fractional bandwidth. The first DPA is a full Monolithic Microwave Integrated Circuit (MMIC) based on UMS <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$0.15-\mu \mathrm{m}$</tex> GaN HEMT technology, while the second version is made of the same MMIC except that its output combiner is replaced by an external circuit designed on a Printed Circuit Board (PCB). Both DPAs achieve an average Power Added Efficiency (PAE) of 38% and 43%, respectively, over a wide fractional bandwidth.