Large-signal MOSFET modeling using frequency-domain nonlinear system identification

Traditional BSIM MOSFET model extraction considers I-V/C-V curve fitting to capture DC non-linearity and S-parameter fitting to capture high-frequency small-signal behavior. This leads to poor accuracy when modeling MOSFETs in large-signal RF circuits such as power amplifiers, which require to model high-frequency large-signal behavior of MOSFETs. In this paper, we proposed an automatic method for automatically modeling high-frequency large-signal behavior for MOSFETs. The input is a pre-characterized MOSFET model and large-signal measurement data. The output is an enhanced model that model not only DC and S-parameter characteristics but also large-signal behavior. Experiments show that the proposed method can accurately capture both the nonlinear and dynamic behavior of RF MOSFET.