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Our customer is a premier defense establishment involved in the development of stealth technology which aims at reducing radar cross section (RCS) of military vehicles and projectiles. An effective way to reduce RCS is by applying coatings of radar absorbent material (RAM) on the surface of vehicle. The RAM coatings could be composed of a single material or a composite mixture for enhanced capabilities. To design these coatings efficiently, their behavior needs to be understood in terms of their scattering parameters.

Zeus Numerix utilized edge based Finite Element Method to develop a generic electromagnetic field solver. Using this solver, scattering parameters of a RAM placed in a waveguide were computed for various frequencies of incident electromagnetic waves. The solver uses unstructured meshes with tetrahedral cells and solves the linear system of equations to obtain electric fields at the edges of the tetrahedrons. The field values are then used to calculate the reflection and transmission coefficient which are then used to compute S-parameters. Zeus Numerix also developed an analytical tool to compute effective electrical permittivity and magnetic permeability of a composite mixture material from the microstructure of the base material and randomly distributed fillers.

The client was provided with the generic software which takes geometrical and electromagnetic properties of the material as inputs and computes its S-parameters. They used the software to study various types of material and composites to design the most effective coating for reducing RCS. This significantly saves time and cost earlier required in analyzing various coatings using experiments.