Kristoffer Andersson received the M.Sc. degree and Ph.D. degree in electrical engineering from the Chalmers University of Technology, Göteborg, Sweden, in 2001 and 2006, respectively. Until 2013, he was an Assistant Professor with the Microwave Electronics Laboratory, Department of Microtechnology and Nanoscience (MC2), Chalmers University, during which time he was involved with the modeling and characterization of gallium–nitride high-frequency transistors. Since 2013, he has been a Senior Researcher with Ericsson Research AB, Göteborg, Sweden, where he is involved with gallium–nitride monolithic microwave integrated circuits (MMICs) and millimeter-wave 5G front-ends.