Harmonic balance evaluation of nonlinear microwave circuits-a tutorial approach

The method of harmonic balance is discussed as a general approach to converting a set of differential equations into a nonlinear algebraic system of equations that can be solved for the periodic steady-state solution of nonlinear microwave circuits. Two different techniques are applied to solve the algebraic system of equations: the fixed-point method and the modified Newton-Raphson method. The implementation of the different numerical algorithms with harmonic balance is described. The choice of the appropriate optimization technique dramatically reduces the time required for a simulation, and allows harmonic balance to be applied to very complicated circuits in an efficient way