Baştüzel Çakmak, Özlem
Radio frequency (RF) power amplifiers (PAs) are the most crucial part for the development of high performance front-end RF and microwave systems. Power transistor is the key component of a power amplifier, which should be accurately modeled to provide good correlation between simulation and measurement results. Bare die transistor needs to be packaged, before attaching on printed circuit boards (PCBs) to provide protection, easy fabrication and prevent mechanical issues. In recent years, Gallium Nitride (GaN) High Electron Mobility (HEMT) transistors are popular because of high output power, high reliability and high frequency operation capabilities. This thesis reports modeling of an air cavity ceramic package for bare GaN HEMT die transistor to design 0.5-3 GHz broadband PA with 50 W output power and 40 % drain efficiency. For package modeling, two approaches are utilized which are lumped element model based on analytical equations and a numerical model based on full-wave electromagnetic (EM) simulations by Advance Design System (ADS) software. The package and designed PA are fabricated and measured for performance validation. The results show a very good agreement with the simulations, indicating the validity of the modeling methodology.


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Citation Formats
Ö. Baştüzel Çakmak, “MODELING OF GAN POWER TRANSISTOR PACKAGE FOR DESIGN OF BROADBAND HIGH-POWER AMPLIFIER,” M.S. - Master of Science, Middle East Technical University, 2022.