A 2.5-Dimensional Miniaturized Frequency Selective Surface based on Convoluted Geometry

A miniaturized-element frequency selective surface (FSS) based filter geometry has been designed and analyzed in this paper. The geometry is made of convoluted meander lines printed on both sides of a dielectric and the patterns are joined by metallic vias engraved through the substrate, thereby reducing the operating frequency. This results in a compact 2.5-dimensional filter geometry exhibiting a combination of bandstop and bandpass responses, having unit cell dimensions of 0.044λ × 0.044λ, where λ is the operating wavelength at the lowest operating frequency (1.10 GHz). The proposed topology is four-fold symmetric as well as angularly stable for different polarizations. Parametric variation and other set of analyses have also been carried out to explain the operating principle of the proposed FSS. The proposed FSS design can be considered as a potential candidate for several radome applications.