Application of spectral-balance to the design of non-linear microwave circuits. Steady-state response, sensitivity analysis and optimization

The authors give an overview of the harmonic-balance technique, especially its extension to analysis of nonlinear circuits under multitone excitation. Emphasis is placed on the Newton-Raphson method for the solution of the circuit equations, which yields simultaneously the steady-state response and the sensitivities of the response with respect to circuit parameters. The Jacobian of the spectral-balance equation provides a means to follow the solution curve for varying circuit parameters, with a small number of Newton-Raphson iterations. This renders the steady-state performance optimization of nonlinear circuits realistic and very attractive