Methods for building polynomial device models for frequnecy domain nonlinear analysis

This paper reviews the needs for polynomial device models and compares six different model fitting techniques that perform a least square error type polynomial fitting either in the I-V or spectrum domain. Fitting the model separately for each amplitude level a 3rd-degree model is accurate within a couple of dBs even in highly nonlinear operating mode. However, the choice of the fitting method affects the fitting results and hence the simulation accuracy.