Analysis of the Transient Dynamics of Coupled-Oscillator Systems

A realistic reduced-order formulation of systems containing several transistor-based oscillators, such as coupled-oscillator networks, is presented. The formulation is able to predict the oscillation build-up and other transient effects for the first time to our knowledge. The individual oscillator models are constructed from a nonlinear admittance function extracted from circuit-level harmonic-balance simulations. These models are used to derive a nonlinear differential-equation system able to describe the transient behavior of the entire structure. For illustration, the method has been applied to a coupled-oscillator system at 5 GHz, obtaining very good agreement with circuit-level envelope transient (when applicable) and with measurements.