An Eight-Scallop Flower-Based Ultrathin and Bidirectional Multiple Passband FSS

Abstract

A new, extremely thin, and bidirectional microwave passband FSS with multiple bands has been developed. This FSS consists of an FR4 sandwiched between three concentric metallic eight-scallop flower (ESF) rings on the front side and corresponding complementary geometry on the back side. The thickness of the suggested FSS at the lowest transmission band is λ_L⁄260. The design is insensitive to polarization and exhibits a stable response for both the TE and TM wave cases. The conformality of the design is tested for both inward and outward geometries, and further, the response of the passband FSS design is analyzed for different parameter variations. A prototype is fabricated using standard printed circuit board (PCB) techniques for practical verification. The performance of this passband FSS is validated using a circuit model and the free-space measurement technique. The outcomes are in close agreement with the simulated and circuit analysis results.