Enhanced Thin-Wire Representation Models in a High-Order FDTD/TLM Method for Electrically Large Microwave Applications

A compact class of general-radius thin-wire representation models combined with a 3-D high-order finite-difference time-domain/transmission-line matrix technique is developed in this paper for realistic large-scale microwave applications. Founded on an appropriately formulated set of telegrapher´s equations via an error-controllable interpolation process, the new methodology efficiently approximates propagating waves along the radial direction of the wire and subdues artificial instabilities. Furthermore, through a nonoverlapping grid discretization algorithm, the hyperbolic character of Maxwell´s laws is physically preserved and lattice reflection errors are extensively minimized. So, tilted and circular-loop wires of arbitrary orientation, pertaining to mesh axes, are accurately coupled with the hybrid method. These enhanced features are successfully validated by several composite media configurations.