New oblique thin wire formalism in the FDTD method

In the FDTD method, the Cartesian meshing is a critical point for conforming structures and small geometries. For thin wire formalism, one cumulates small section with a problem of conforming to the Yee´s cell and fast variation of both looping magnetic field and radial electric field close to the wire. Among all previous thin wire published models, only Holland´s approach has evolved toward inclined wires. Hence the works of Ledfelt and Edelvik show that it is possible to have a wire´s behaviour independent of its location in the Yee´s cell or its obliquity. Our new approach compared to is justified by the necessity to deal with a junction between several oblique wires. Indeed is not extended for multiwire junction because the coupling between the wire current and the electrical field uses a cylinder-shaped stencil with a section superior to the FDTD cell size and so it is too difficult to suit correctly to a junction with more than two wires. To avoid this problem, we propose a technique where the coupling between the wire and the FDTD meshing is limited to only the cells that contain a part of the wire.