Multiband Enhanced Angular Stability Polarization Insensitive Band-Stop FSS for Unwanted EM Shielding

In this paper, a compact triple band-stop frequency selective surface (FSS) is proposed for shielding unwanted electromagnetic (EM) radiation at 2.41 GHz, 3.16 GHz, and 5.86 GHz. The design exhibits polarization-insensitive behaviour and superior angular stability, making it suitable for shielding applications. The FSS is based on a modified square ring unit cell, achieving precise triple-band rejection characteristics. The proposed model is implemented on the FR4 substrate with relative permittivity 4.4, thickness 1.6 mm and loss tangent 0.02. The unit cell dimension of the proposed unit cell is 12.2mm× 12.2mm ×1.6mm. The simulation has been done by using High Frequency Structure Simulator (HFSS) for study of TE (Transverse Electric) and TM (Transverse Magnetic) polarizations under normal incidence. The proposed FSS covers 1.96 – 2.54 GHz, 2.8 – 3.52 GHz, and 4.99 –6.73 GHz frequency bands, corresponding a<-10 dB attenuation level. From the TE and TM responses, polarization insensitivity is also verified with wide-angle coverage of°.