Addressing Instability in Wide Bandwidth High Power Amplifiers

Addressing stability in power amplifiers (PAs) over wide bandwidths is one of the biggest challenges that RFPA designers must overcome. Standard techniques include adding resistive (lossy) elements, however, this approach may cause problems with heat dissipation and a reduction in amplifier efficiency. In addition, PAs connected directly to antennas face additional instability issues in that the antenna load impedance can vary considerably, resulting in potential oscillations. A suitable stabilization strategy, validated through circuit simulation, is required to ensure that the amplifier is unconditionally stable regardless of the source/load impedances. This webinar presents the use of stability analysis techniques to identify potential instability in a 200-W PA and design techniques to stabilize the amplifier.

Presenter Bio
Dr. Dominic FitzPatrick has been involved with the design of solid state RF & microwave amplifiers for over 30 years. He holds a B.Sc. and an M.Sc. in solid-state microwave physics from the University of Portsmouth, England, and a Ph.D. from Cardiff University, Wales. He has been the technical director of two UK companies designing and manufacturing RF/microwave frequency, solid-state PAs (SSPAs) and in 2010 he started PoweRFul Microwave, a consultancy specializing in SSPAs. In April 2019 Dr. FitzPatrick joined Ametek-CTS as the head of amplifier development.
He is a co-author of The Handbook of RF and Microwave Power Amplifiers,
Cambridge University Press.