Dr. Jon C. Freeman is a research engineer in the Electron and Optical Devices Branch at the National Aeronautics and Space Administration's Glenn Research Center at Lewis Field in Cleveland, Ohio. His areas of research are particle-in-cell codes for simulation of electron guns for traveling wave tubes, analysis and design of gallium nitride (GaN) high-electron-mobility transistors for power amplifiers for space applications, and extreme temperature environments for Earth-based applications.

Dr. Freeman earned his bachelor’s, master’s, and doctoral degrees in electrical engineering from Purdue University in 1966, 1971, and 1972, respectively. He began his career as a member of the technical staff with Bell Telephone Laboratories in Andover, Massachusetts. There he designed impact avalanche transition time (IMPATT) and Gunn diode oscillators for microwave radio systems. He also developed gallium arsenide (GaAs) amplifiers for many applications. Dr. Freeman became an assistant professor at Michigan State University in 1979, where he taught in the Electrical Engineering Department. His teaching duties included both undergraduate and graduate courses in field theory, antennas, microwave principles, and solid-state electronics. His research centered on coupling of waves in gaseous and solid-state plasmas, optimization of power and noise in solid-state oscillators, and solid-state traveling wave amplifiers. In 1986, Dr. Freeman worked briefly for Tracor Aerospace Austin, Inc., but left to join NASA in Cleveland, Ohio. At NASA, he has worked as a systems engineer in the Advanced Communication Technology Satellite (ACTS) Program; as a developer of microwave circuitry for the high-data-rate ground station receiver, which included the rain-fade simulator; and as a local expert in forward error correction codes, and their applications to satellite channels.