Parameter extraction for large signal noise models and simulation of noise in large signal circuits like mixers and oscillators

This paper shows how to obtain an equivalent circuit model for bipolar transistors and FEITs to generate a bias-dependent model. The bias-dependent model is required as a seed to obtain starting values for a large signal model. Particularly in the case of calculating noise under large signal conditions, the bias-dependent noise parameters for both bipolar transistors and FETs have to be obtained. For verification purposes, these methods have been implemented in the nonlinear circuit simulator, Microwave Harmonica. We have employed double balanced diode mixers, both active and passive (switching) FET mixers as well as a variety of oscillators to show that the nonlinear noise analysis capabilities are verified in these applications.