Experimental Validation of a Four-Way Outphasing Combiner for Microwave Power Amplification

• Main Authors: Barton, Taylor W. (Contributor), Dawson, Joel L. (Contributor), Perreault, David J. (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science (Contributor), Massachusetts Institute of Technology. Microsystems Technology Laboratories (Contributor)
• Format: Article
• Language: English
• Published: Institute of Electrical and Electronics Engineers (IEEE), 2014-05-15T14:14:29Z.
• Subjects: Article
• Online Access: Get fulltext

This letter presents a 2.14 GHz, four-way power combining and outphasing system for high-power amplifiers such as those in radio basestations (RBS). The combiner is ideally lossless, and enables power control through load modulation of the power amplifiers (PAs). A discrete-component power combiner is designed and characterized, and combined with inverse Class-F PAs using GaN HEMT devices to develop a complete PA system. We demonstrate the effectiveness of the system over a range of outphasing control angles. This first-ever microwave implementation of the outphasing system has a peak CW drain efficiency of 68.9%, with efficiency greater than 55% over a 5.5 dB power range. It provides an average modulated efficiency of 57% for a W-CDMA signal with 3.47 dB peak to average power ratio (PAPR) at 42 dBm output power.
Massachusetts Institute of Technology. Center for Integrated Circuits and Systems