Modeling an FSS with a simple equivalent circuit has been
reported in [11]. In general, the FSS structures can be
categorized into patch-type elements and aperture-type
elements. Element shape is not just limited to square loops or
patches, the element can be circular rings, or others convoluted
shapes. Many factor that influence the FSS response such as
FSS's element geometry, the dielectric substrate which supports
the FSS, and the signal incident angles. The element geometry
is a fundamental aspect a designer should determine in FSS
design. Both the element conductivity and the dielectric
substrate's permittivity have a great influence on FSS design.