Interfacing Thin-Wire and Circuit Subcell Models in Unstructured Time-Domain Field Solvers

A method for driving and terminating Holland-Simpson based thin-wire models by arbitrary lumped-element circuits is proposed. The approach uses the fact that these thin-wire models result in modified Telegrapher´s equations, and interfacing transmission lines and lumped-element circuits is straightforward. The thin-wire voltage and current at a circuit/wire junction can be written in terms of circuit nodal voltages and branch currents, permitting the circuit solution to act as a boundary condition for the thin-wire system. In this work, we provide the circuit/wire interfacing conditions and combine circuits with Edelvik´s Holland-Simpson model that permits thin-wires to be arbitrarily oriented within an unstructured mesh. Edelvik´s work, previously implemented for finite-difference and finite-element time-domain solvers is formulated for the finite-volume method. Numerical and experimental results for circuit-driven thin-wire antennas are provided to validate the method.