Direct nonlinear power MESFET parameter extraction and consistent modeling

A novel method is developed which permits a direct nonlinear FET parameter extraction of the gate source capacitor and diode, the drain current generator, and the avalanche breakdown characteristics from large-signal waveform measurements. Differences between the DC and RF characteristics of the drain current generator and the breakdown characteristics are observed and interpreted. The measured FET output power and phase spectra are compared with simulated results for different RF models of the nonlinear drain current generator. The proposed method is a valuable instrument for the analysis of the existing high-frequency FET nonlinearities and can be used to improve large-signal FET models.<>