An ultra large polarisation independent bandstop frequency selective surface for the security of WiMax and WLAN application

The important parameter of the wireless devices is its security from unwanted signals or unlicensed bands. As the interference from undesired signals not only degrade the system performance but also hinders the security. In this work, a novel single layer FSS has proposed that operates as bandstop filter at 1.8GH, 3.5GHz and 5.5GHz. The proposed design consists of three elements by virtue of which the FSS Resonates at 1.8GHz, 3.5GHz, 5.5GHz. The dimension of superstrate is 0.24λ × 0.24λ and dielectric constant of 4.4mm with thickness 1.6mm and tangential loss 0.025. Surface current and various incident angle distribution has illustrated to show much clear resonance behavior of FSS. The proposed structure holds great angular independence as the structure is symmetrical in both TE (Transverse Electric) and TM (Transverse Magnetic) field. The CST MW simulation software is used for designing and simulation of the results. A good reflection curves are observed at 1.8GHz, 3.5GHz, and 5.5GHz.