An innovative algorithm for circumventing numerical stiffness in time-domain simulation of strongly nonlinear multirate RF circuits

This paper proposes an innovative computer-aided design tool especially conceived for the efficient numerical simulation of strongly nonlinear RF circuits whose state variables are all fluctuating in a rapidly changing time scale, but evidence disparate rates of change in a slow envelope time scale. The proposed numerical technique is able to circumvent numerical stiffness and can be seen as a mixed mode algorithm that results from a combination of the method of lines based on multirate Runge-Kutta (MRK) schemes and the envelope transient over shooting technique. Simulation tests conducted in an illustrative example reveal promising results in terms of computational effort, over previous methods recently proposed for the simulation of the same category of circuits.