Analysis and experiment for drain bias dependence of IMD sweet spots in GaNHEMT power amplifier

Abstract

In this article, we propose the drain bias dependency on the intermodulation distortion (IMD) sweet spots of a gallium nitride (GaN) high-electron mobility transistors power amplifier (PA). Using the mathematical approach by the I-DS-V-GS, characteristic curves and two-tone distortion products, the positions of the IMD sweet spots according to drain bias as well as gate bias and input power are predicted and well-matched with the measured results. (c) 2008 Wiley Periodicals, Inc.