Efficient and reliable numerical algorithms for nonlinear microwave computer-aided design

The numerical solution issues that arise in the large-signal analysis of nonlinear microwave circuits are addressed at a fundamental level. The focus is on the nonlinear harmonic-balance equations (HBEs) arising from the application of the harmonic-balance (HB) method, the approach predominantly used in nonlinear microwave computer-aided design packages. Theoretical figures of merit are used to evaluate potential numerical methods for this application. Nonconvergence mechanisms that plague present HBE solvers are identified and discussed along with other previously neglected solution issues. Five novel so-called polyalgorithms have been developed for the HB method that bypass nonconvergence scenarios and possess an increased level of numerical efficiency and reliability.<>