Microwave FET model identification based on vector intermodulation measurements

In this paper an identification procedure for an FET analytical model oriented to μm- and mm-wave applications is presented. It is based on low-frequency large-signal measurements to determine with a high level of accuracy the nonlinear current source parameters. In addition, vector intermodulation measurements are used for the identification of the strictly nonlinear dynamic effects of the intrinsic device. As case study, the identification technique is applied to a 0.15-μm GaAs pHEMT. The extracted model is validated through comparison with nonlinear measurements carried out under conditions different from the ones used for model identification. A very good agreement with measurements has been achieved, despite the small number of data used to determine the model parameters.