Modeling HEMT intermodulation distortion characteristics

The significance of the nonlinearity of HEMT capacitance models to the pred iction of intermodulation is investigated. Three capacitance models, one li near and two with contrasting nonlinear behavior, are shown to exhibit almo st identical performance. It is concluded that the nonlinearity of the low- frequency model is the dominant distortion generating component. Developmen t of capacitance models with accurate high-order derivatives is unwarranted without an accurate de model. Therefore, careful characterization of the d rain current description is most important for the successful circuit simul ation. (C) 2000 Elsevier Science Ltd. All rights reserved.