ECEE Seminar Series Spring 2015 Thursday, April 2, 2015 11:00 – 12:15pm ECEE 1B32 Investigating Element Pattern Performance in Phased Arrays with Radiation Reconfigurable Antennas Tyrone Roach Abstract: Reconfigurable antennas have drawn considerable attention by researchers over the last several years. Due to their ability to reconfigure pattern, frequency, and polarization characteristics, these antennas have become an important and desired feature to meet the demands posed by the RF front-ends of modern and future wireless communication systems. The numerous degrees of freedom reconfigurable antennas possess make them integral candidates for emerging technologies. Even though, more recently, the development of pattern reconfigurable antennas that may be suitable for such applications has grown, questions still remain about the practical capabilities and limitations these antennas can offer in larger platform application that utilize phased arrays. Do they perform any different than traditional fixed-pattern antenna elements across the various reconfiguration states in an array environment? Ultimately, why choose a reconfigurable antenna vs. a traditional antenna? As a step toward answering these questions, the work presented in this talk explores the performance characteristics between reconfigurable antenna elements and their various reconfiguration states when situated in an array environment. Developed pattern reconfigurable antenna models, utilized in previous research, are incorporated into an electromagnetic simulation tool to predict the active reflection coefficient and the active element pattern using Floquet modes. Due to the effects of mutual coupling, the candidate reconfigurable antennas had to be redesigned from their nominal isolated element design in order to share a common scan impedance bandwidth across reconfiguration states. Results will compare and contrast array performance metrics for the different antenna designs to that of a traditional fixed-pattern antenna element and illustrate the potential positive impact in performance when adding the element of reconfigurability to phased-array antenna systems. Biography: Dr. Tyrone Roach graduated with a B.S. degree in Electrical Engineering from the University of Nevada-Las Vegas (Magna Cum Laude) in 2001. He subsequently earned the M.S. and Ph.D. in the same field from the University of Illinois at Urbana-Champaign in 2005 and 2010, respectively. During his tenure as a graduate student, he authored two refereed journal papers and over ten conference proceedings. He was also the recipient of numerous fellowships and awards, including the Raj Mittra Outstanding Research Award. In 2010, he joined the Sensors and Electromagnetic Applications Laboratory at the Georgia Tech Research Institute (GTRI) as a research engineer. Since joining GTRI, Dr. Roach has developed a technical career in a variety of applied research areas that include phased array antenna design, electromagnetic modeling and simulation of complex structures, and analysis and characterization of foreign threat radar systems. He has contributed technically to over 15 sponsored programs which have led to multiple key delivered products, numerous written final reports and presentations to the customer. His research interests include system level integration of phased array antennas with adaptive and multifunction characteristics, antenna array reconfigurability, pattern synthesis, and array beamforming. Dr. Roach has served as a paper reviewer for select IEEE journal and international conference publications. He has been a member of the IEEE since 1998 and is a current member of the IEEE Antennas and Propagation Society. Light refreshments will be served.