Waveform Krylov subspace methods for tightly coupled systems

We extend Krylov subspace methods, which are intended for iterative solution of systems of linear equations, to a function space for the solution of circuit problems. Four of the previously untried methods are applied to a tightly coupled circuit to illustrate the convergence properties of these methods. Numerical results showed that convergence was achieved for many cases where the conventional waveform relaxation method would fail