Behavioral modeling and simulation of a parametric power amplifier

Parametric amplification is a well known technique for achieving power gain at microwave frequencies. By modulating a nonlinear reactance using a large (pump) signal, a smaller (source) signal is up-converted with gain. The ideal gain predicted by the Manley-Rowe relations are theoretically limited by the ability to suppress the pump signal and unwanted mixing products of the nonlinear reactance. When using ideal nonlinear reactances (i.e. infinite Q) parametric amplification is lossless, resulting in 100% conversion efficiency of the pump signal power to the desired mixing product. In this paper we develop a behavioral model to predict limitations in gain driven by changes in a nonlinear capacitance, which enables practical circuit design. The model is validated by circuit simulations, and by a breadboard parametric mixer.