Coupled circuit-electromagnetic simulation using time domain integral equation

Time-domain integral equation solvers are highly suited for analyzing the performance of coupled circuit-electromagnetic (EM) systems when broadband information is required or nonlinearities in the system have to be modeled accurately. In this paper, we present a novel coupling scheme for hybridizing TDIE with modified nodal analysis (MNA) used in circuit simulation of linear and nonlinear circuits. The coupling scheme is based on the concept of a coupling current that bridges circuit and EM domains. This approach has the advantage of modeling arbitrarily shaped structures with surface-only formulations, and of incorporating skin effects automatically with no volumetric meshing. The method enables direct solution of circuit- EM equations without the need for generating port models, and permits both circuit and EM excitations which has potential as a signal integrity and as an EMI/EMC modeling tool.