Transistor characterization and modeling and the use of embedding device models for the design of microwave power amplifiers

Circuit-based large-signal device models remain extensively used to design integrated and hybrid microwave circuits. It has been recently demonstrated that device models can also be profitably applied under the form of a nonlinear embedding device model to help with the synthesis of multi-transistor power amplifiers (PA) such as Doherty PAs. In this paper we shall discuss this new design process from device modeling to PA design. First an example of an Artificial Neural Network (ANN) SOS-MOSFET model directly extracted from large-signal measurements will be reviewed and its companion ANN nonlinear embedding device model presented. Nonlinear embedding device models can be implemented for other models such as the Angelov model to design PAs. A general methodology for designing two-transistor Doherty or Chireix PAs using an embedding device model will be presented and preliminary simulation results on the design of a GaN Chireix amplifier using an Angelov nonlinear embedding device model will be reported.