Distributed power amplifier with novel integration technique of broadband impedance transformer using pseudomorphic HEMT and gallium nitride HEMT

Abstract

An advance approach of distributed power amplifier (DPA) design has been introduced in this study, based on broadband impedance transformer integration. By identifying the DPA's optimum impedance over the frequency range with load pull measurement technique, the impedance transformer with mixed-lumped elements using real-frequency technique is designed. The prototype of the transformer network is integrated with the three-stage DPA with pseudomorphic High-Electron-Mobility Transistor (HEMT) and gallium nitride HEMT technologies. Experimental output power performance achieves 40 dBm over bandwidth operation from 0.1 to 2.4 GHz, and the power added efficiency reaches 30% in average with gain of 30 dB. This proposed technique is essential to maximise DC-radio frequency conversion to the load termination and the transformer is having advantages over size area, implementation in small form factor and low-cost approach particularly compatible for radio communications applications.