Since the elements of the periodical structures are small, it is recommended to work in centimeters or millimeters. The units can be modified in the bottom bar of the user interface. The measurement units used in this document are centimeters.
The user can choose from a wide range of geometries available for the generation of periodical structures. The most common are in the Cell - FSS Primitives menu, but it is possible to use other primitives defined in the Geometry menu.
The unit cell must be defined. The cell is composed by a dielectric layer and a metal square patch at the top. The dielectric layer has a thickness of 0,2 centimeters.
In order to define the first interface (without geometry) create a point using the Geometry → Point → Single Point option. The point will be defined at the origin coordinates (0, 0, 0).
Then the metallic patch is defined using Cell → FSS Primitives → Plane. This patch is centered at the origin at a height of 0.2 centimeters using the parameters shown in the next figure.