Design of a Novel 2.5D Frequency Selective Surface Element Using Fibonacci Spiral for Radome Application

摘要

In this paper, a novel 2.5D frequency selective surface (FSS) element is proposed based on the Fibonacci spiral. A dual resonance has been obtained using the combined effect of the single square loop and Fibonacci element. The same pattern is printed on either side of the substrate and tightly coupled with the help of metallic vias to form a 2.5D FSS element. The structure shows negative ε and negative μ characteristics at frequencies. Then, a multilayered radome wall has been demonstrated by embedding the proposed FSS element in the dielectric skin. The radome structure shows better angular stability for a wide angle of an incident electromagnetic wave up to 60°. The proposed structure is found to show band-pass characteristics in the frequency range of 9.5-12.58 GHz with very good transmission efficiency (>90%) having a very low insertion loss of 0.02 dB in the operating frequency range.