Chapter
Combining Structures
Dr. AMIR MORTAZAWI
Department Electrical Engineering and Computer Science
University of Michigan, Ann Arbor, MI
| Organizer: IEEE Toronto Section, Electromagnetics and Radiation Joint Chapter |
| Title: Quasi-Optical And Extended Resonance
Power Combining Structures |
| Speaker: Dr. AMIR MORTAZAWI Department Electrical Engineering and Computer Science University of Michigan, Ann Arbor, MI |
| Abstract: The power produced from solid-state devices drops drastically as their frequency of operation approaches the millimeter-wave region. Furthermore, most communications and radar systems require much more power than is available or expected from a single solid-state device. Conventional power combining techniques are not applicable at millimeter-wave frequencies due to their inherent losses at these frequencies. In this talk I will present novel circuit level and spatial power combiners for the design of microwave and millimeter- wave power amplifiers. The first technique that will be presented is based on Extended Resonance. The theory and the design of power amplifiers based on this technique will be discussed. Furthermore, due to its compact size, this power combining technique is applicable for the design of on chip power amplifiers. The application of this technique to the construction of high efficiency linearized amplifiers will also be explored. In the second part of this talk, the design of spatial power combining amplifier arrays will be presented. These amplifiers are intended to replace Traveling Wave Tubes at Ka-band (26 GHz to 40 GHz) and W-band (75 GHz to 110 GHz). The highlight of our work is a 25W amplifier array at Ka-band developed through our collaboration with Lockheed/Martin Corp. Important issues such as uniform excitation and tolerance to multiple device failures will be discussed. |
| Biography: Dr.Amir Mortazawi obtained B.S. degree in electrical engineering from the State University of NY, Stony Brook, in 1987, M.S. and Ph.D. degrees in electrical engineering from the University of Texas at Austin, in 1988 and 1990, respectively. In 1990, he joined the University of Central Florida, Orlando, FL, as an Assistant Professor where he was promoted to Associate Professor in 1995. In August of 1998, he joined the North Carolina State University as an Associate Professor of Electrical Engineering. In Fall 2001, he joined the University of Michigan, Ann Arbor as an Associate Professor. Dr. Mortazawi is co-chair of IEEE MTT-16 committee Phased Arrays and chair of the IEEE-MTTS Technical Program Committee on Active and Quasi-Optical Arrays. He was an Associate Editor for the IEEE Transactions on Antennas and Propagation from 1998-2001. Dr. Mortazawi's research interests include millimeter-wave power combining oscillators and amplifiers, quasi-optical techniques, frequency agile materials and nonlinear analysis of microwave circuits. |
| Time and Location: Friday, October 26th, 2001, at 2:00 pm Medical Sciences Building, Room MS 4171
The Institute of Electrical and Electronics Engineers,
Toronto Section Send comments to tor.sect@tor.ieee.org |
