Scattering characteristics of FSS comprised of L-shaped and one-turn helix shaped conductors for TE and TM excitation

The boundary value problem of doubly infinite periodic conductor arrays of L-shape and one-turn helix shape frequency selective surfaces (FSSs) backed by dielectric substrate are investigated by using modal expansion method. The moment method is employed by expressing the current induced on the metallic surfaces in terms of Piecewise Sinusoidal (PWS) functions. The variation of the reflection and transmission coefficients versus frequency for dielectric backed FSS is investigated for both transverse electric and transverse magnetic wave excitations at normal incidence. Reflection coefficients of dielectric backed FSS at normal and oblique incidence are plotted against frequency. The correctness of the algorithm is ensured by comparing the numerical results with the experimental results in the literature for an FSS composed of strips and proved to be as good. Tel.: +90-342-3601200 ext: 2131