Electromagnetic modeling of anisotropic medium and applications

A stable method of calculation of the electromagnetic response of planar anisotropic laminates to an active source with limited distribution along the strata direction is developed. The laminates can be sandwiched between isotropic, anisotropic, or perfectly conducting covers/substrates. The source is either inside the laminates or in the cover or substrate. Based on the propagator matrix method, the proposed method relies on downwardand upward-going recurrence relations which transfer the tangential electric and magnetic fields from one interface to the next in accord with the boundary conditions, even when an distributed active source is embedded between the two interfaces. The electromagnetic response of general anisotropic laminates to active sources within or above them can thus be efficiently and accurately computed without further consideration of the conventional numerical instability issue. Some focus is put also on the highly practical case of electrically uniaxial materials with anisotropy axes parallel with the strata (fiber-reinforced composite panels). The method works for conductive and dielectric materials, and from eddy-currents to microwaves, without specific tuning, as it will be illustrated in the presentation by a number of examples in comparison to the literature. Once the incident field in a non-damaged structure has been obtained, then the case of a damaged layered structure is handled via a method of moments based on rectilinear discretization and windowing. The numerical approach is validated with comparisons to known results (isotropic case) and FEM computations (isotropic and anisotropic cases), illustrating efficiency and accuracy.