A Single Layer Interdigitated Loop Elements-Based Miniaturized Frequency Selective Surface for WLAN Shielding

This article unveils a compact, single-layer frequency selective surface (FSS) that employs interdigitated loop elements for shielding electromagnetic (EM) radiations emanating from the hotspots of wireless local area networks (WLANs). The proposed FSS geometry resonates at 2.4 GHz and guarantees a 10 dB shielding effectiveness (SE) to incident EM waves with frequencies ranging between 1.77 GHz and 3.04 GHz. Furthermore, the coincident transmission coefficient traces signify the polarization insensitivity of the proposed FSS design for two different modes, namely transverse-electric (TE) and transverse-magnetic (TM). This structure demonstrates consistency in offering 10 dB SE to WLAN signals for incident angles up to 75° as the unit cells are densely-packed with each having dimensions of 0.05\,\,\lambda _{0} \times 0.05\,\,\lambda _{0} , where \lambda _{0} is the free space wavelength at resonance. SE from an equivalent circuit model (ECM) and real-time measurements with a fabricated prototype in an anechoic chamber endorse the authenticity of simulated results.