Events Calendar

Integrated Systems Seminar Series

Speaker: Prof. Zoya Popovic, University of Colorado – Boulder

Talk Title: Microwave GaN Power Amplifiers for Efficient Communication and Radar Transmitters

Abstract: This talk will present an overview of the activities in the microwave and antennas group at the University of Colorado, Boulder, followed by a more detailed discussion of various techniques for obtaining high-efficiency transmitters for non-constant envelope communication and radar signals. Several efficient amplifiers will be presented, for applications such as wind-profiling radar with 3-kW LDMOS pulsed 449-MHz PAs with power added efficiencies (PAE) greater than 65%, to S-band hybrid GaN PAs with 10W output power and PAE>80% and X-band 10-W MMIC GaN PAs with PAE>60%. These amplifiers are integrated into transmitters that use several architectures to maintain efficiency for varying amplitude signals, such as supply modulation, outphasing and harmonic injection at the output. Several transmitters for envelope signal bandwidths exceeding 100MHz, over 6dB peak-to-average ratios, and total system efficiencies greater than 50% will be presented. Since high efficiency is accompanied with high nonlinearity, techniques for linearization will also be discussed.

Biography: Zoya Popovic is a Distinguished Professor and the Hudson Moore Jr. Endowed Chair of Electrical Engineering at the University of Colorado. She obtained her Dipl.Ing. degree at the University of Belgrade, Serbia, and her Ph.D. at Caltech. She has graduated 46 PhDs and currently advises 16 doctoral students in various areas of microwave engineering. She is a Fellow of the IEEE and the recipient of two IEEE MTT Microwave Prizes for best journal papers, the White House NSF Presidential Faculty Fellow award, the URSI Issac Koga Gold Medal, the ASEE/HP Terman Medal and the German Humboldt Research Award. She has a husband physicist and three daughters.

Host: Prof. Hossein Hashemi, Prof. Mike Chen

Location: Hughes Aircraft Electrical Engineering Center (EEB) - 248

Audiences: Everyone Is Invited

Contact: Hossein Hashemi