Kazuya Yamamoto received the B.E., M.E., and Ph.D. degrees in electrical engineering from Osaka Prefecture University, Sakai, Japan, in 1988, 1990, and 1998, respectively. Since joining the Optoelectronic and Microwave Devices Laboratory, Mitsubishi Electric Corporation, Itami, Japan, in 1990, he has been engaged in the research and development of GaAs-based analog and digital ICs—PAs, antenna switches, prescalers, and quadrature modulators—for mobile communications. He has also been engaged in the research on circuit design techniques of high-speed analog and digital ICs—preamplifiers, electro-absorption (EA) drivers, and decision circuits—for optical fiber links. He is currently the Chief Engineer of the High Frequency Device Department, High Frequency and Optical Device Works, Mitsubishi Electric Corporation. He is also a Visiting Lecturer with Osaka Prefecture University, where he holds the Chair of microwave device and circuit engineering for microwave applications. He was an Associate Editor of the Institute of Electronics, Information, and Communication Engineers of Japan (IEICE) Transaction on Electronics (English version) between 2008 and 2014. He served on the 2014 Asia-Pacific Microwave Conference (APMC) Technical Program Committee. He was also the Guest Editor of the 2022 IEICE Transactions on Electronics Special Issue on microwave and millimeter-wave technologies. His current research interests include GaN-based power amplifiers, millimeter-wave RFICs, and chip/chip-less RFIDs. Dr. Yamamoto is a senior member of the IEEE and IEICE. He serves on the IEEE MTT-S, Technical Committee (MTT-9), the International Microwave Symposium (IMS) Technical Paper Review Committee, and the IEEE BiCMOS and Compound Semiconductor Integrated Circuits and Technology Symposium (BCICTS) Technical Program Committee.