He is presently Kesight Research Fellow at Keysight Technologies (formerly Hewlett-Packard and Agilent Technologies) in Santa Rosa, CA. His current responsibilities include nonlinear device and behavioral modeling, large-signal simulation, and nonlinear measurements. Dr. Root is well-known as a pioneer of measurement-based nonlinear device and behavioral modeling. He was elevated to IEEE Fellow in 2002 for “contributions to nonlinear modeling of active semiconductor devices.” He was selected as an IEEE MTT-S Distinguished Microwave Lecturer from 2006-2008, and is a member of the MTT-S Speakers Bureau. Dr. Root is a reviewer for the IEEE MTT-S Transactions on Microwave Theory and Techniques and other technical journals and international conferences in the field. He is Past Chair of the IEEE MTT-1 Working Committee on Computer-Aided Design. Dr. Root has well over 100 peer-reviewed technical publications. He is a co-author of the book X-parameters, Cambridge University Press, 2013, and co-author and co-editor of Nonlinear Transistor Model Parameter Extraction Techniques, Cambridge University Press, 2012, and Fundamentals of Nonlinear Behavioral Modeling for RF and Microwave Design, Artech House, 2005.