OPTIMUM DESIGN OF HIGHLY LINEAR AND EFFICIENT GaN HEMT DOHERTY AMPLIFIER CONSIDERING THE SOFT TURN-ON EFFECTS

Abstract

In this article, we propose the optimum design of a highly linear and efficient Doherty power amplifier (DPA) considering the soft turn-on effects of the GaN HEMT. To compensate for the soil turn-on characteristic and obtain air extended high-efficiency range. the DPA is designed with unequal drain biases. For experimental validations, the carrier and peaking cells or(, designed and implemented with the drain bias of 23 V and 33 V, respectively, using 25-W GaN HEMTs at 2.6 GHz and their tested using a continuous wave and a one-carrier WCDMA signal. The measured results show the superior performance for the proposed GaN HEMT DPA. (C) 2009 Wiley Periodicals. Inc. Microwave Opt Technol Lett 51: 956-959. 2009: Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24210