David PorterfieldOur founder and CEO, David Porterfield, has over thirty years of experience designing millimeter- and submillimeter-wave components and systems. At Virginia Diodes he led the effort to develop high-efficiency and high-power varactor multipliers operating in the band from 30 GHz to 800 GHz. He developed a full line of broadband frequency doublers covering the standard waveguide bands from WR-22 to WR-1.9 (33-600 GHz) and a line of frequency quadruplers. David developed a novel design for varactor frequency triplers operating at frequencies from 90 GHz to 750 GHz where the second harmonic idler is implemented in a way that makes it easy to bias and assemble the tripler. He has developed a line of hybrid-mode frequency multipliers that exhibit high efficiencies approaching those of varactors but with improved bandwidth.

David has served as the primary investigator on numerous SBIR contracts with NASA and the US Army Research Office for the development of terahertz receivers for atmospheric remote sensing, for the development of millimeter-wave Gunn oscillator replacement technology, and the development of terahertz transmitters. He has served as the principal investigator on numerous NASA SBIR contracts for the development of high-frequency ferrite components including low-loss Faraday rotation isolators, low-loss cryogenic isolators, voltage variable attenuators, Y-junction circulators, and hybrid circulators. He has authored over thirty technical papers and numerous trade journal articles.

He is the majority owner of Micro Harmonics Corporation. His areas of expertise include microwave and millimeter-wave component and system design, high frequency linear and nonlinear electromagnetic simulation and design, gallium-arsenide diode technology and ferrite component design. His education includes:

  • University of Virginia, 1998 – Ph.D. Electrical Engineering
  • University of Virginia, 1993 – M.S. Electrical Engineering
  • Georgia Tech, 1989 – Bachelor of Electrical Engineering

David is a member of Wellspring Presbyterian Church in Daleville, VA. He serves as an elder, Sunday school teacher, missions director, and is active in ministry. He seeks to honor God in all things including his business practices.

David Porterfield on Linked-In


Diane has been doing research in the area of ferrite devices in millimeter-wave applications since 2013. She received the MEng (EE) from the University of Virginia in 2014 with a focus of study in microwave engineering. In her last year of graduate study, she wrote two literature reviews titled “Faraday-Rotation Isolators in Microwave Circuits” and “Waveguide Y-Junction Ferrite Microwave Circulators”. Her final semester was spent working on the design of a W-band Faraday-rotation isolator.

Diane joined Micro Harmonics in 2015 and served as senior microwave engineer on a highly successful NASA SBIR developing high-frequency (50-325 GHz) ferrite components. She has been instrumental in helping Micro Harmonics take these products to the commercial market.

Diane also has industry experience in process automation, project engineering, and plant engineering at Borg Warner Chemicals in Morgantown, West Virginia, and Sumitomo Electric, fiber optic cable manufacturer in Research Triangle Park, North Carolina. Prior to joining Micro Harmonics Corporation Diane was an instructor in the engineering transfer program at Virginia Western Community College. Her education includes:

  • University of Virginia, 2014 – MEng. Electrical Engineering
  • West Virginia University, 1982 – BS Electrical Engineering
  • University of North Carolina at Chapel Hill, 1988 (18 hours towards MS, Mathematics)

Diane Kees on Linked-In


Joel Kees joined the company in March of 2022. Prior to that, he worked for CACI as an RF engineer on a small team that developed custom RF solutions such as ground station antenna systems. He performed RF analysis for antenna systems, tested components and systems, and helped deploy these systems.

In graduate school Joel partnered with the Hume Center for National Security and Technology as a research assistant. He developed a blind spectral sensing algorithm that was coupled with machine learning for signal detection and classification. This work laid the groundwork for his thesis “Robust Blind Spectral Estimation in the Presence of Impulsive Noise.”

His education includes:

  • Virginia Polytechnic Institute and State University, 2019 – M.S. Electrical Engineering (focus in digital signal processing)
  • Virginia Polytechnic Institute and State University, 2016 – B.S. Electrical Engineering


Aaron Kees joined our team as the Director of Finance in 2021. He brought with him more than a decade of experience in the world of corporate accounting and finance. A graduate of Virginia Tech, he came to Micro Harmonics from KPMG where he guided multinational and Fortune 500 companies through SEC filings, initial public offerings, mergers and acquisitions, reorganizations, as well as other corporate audits. He also spent time serving as a national instructor for KPMG audit curriculums.

His education includes:

  • Virginia Polytechnic Institute and State University, 2011 – B.S. Accounting and Information Systems
  • Virginia Polytechnic Institute and State University, 2011 – Certificate of Additional Major in Finance

He is licensed as a Certified Public Accountant in Virginia (2012) and North Carolina (2018).

Aaron Kees on Linked-In

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