A generalized node for embedding subwavelength objects into 3-D transmission-line models

The transmission-line modeling (TLM) method is a well-established time-domain numerical algorithm for electromagnetic simulation and has been employed in a wide range of application areas. Producing accurate simulations of problems involving both physically important fine features, such as thin wires, as well as large-scale objects has proved very demanding, both in terms of computer time and memory. Clearly, such problems occur in many electromagnetic compatibility (EMC) applications. A general TLM node has been derived from rigorous field analysis that allows the embedding of almost arbitrarily shaped small objects within TLM cells. In particular, this approach allows the highly important case of short lengths of thin wires which are obliquely orientated to the cell faces to be tackled efficiently and, consequently, piece-wise linear models of arbitrarily routed curved wires to be modeled.