Transparent dual band Wi‐Fi filter for double glazed energy saving window as a smart network

Abstract

AbstractA transparent advanced electromagnetic structure is designed to be used in real‐world Wi‐Fi shielding applications. Concentric square loops as frequency selective surfaces (FSSs) are analytically presented with the Pyrex glass substrate based on the equivalent electric circuit model. The designed FSS window suppresses signals at both 2.5 and 5 GHz bands, and reflects back to the indoor medium. Visible light transmittance of the studied window is achieved as 87%. Accordingly, other electromagnetic communication links can transfer through the designed filter such as cell phone, and radio. The dependency of the proposed window to polarization and angular variations is examined numerically, which shows stable frequency response at 2.5 GHz and an acceptable one for 5 GHz. As a figure of merit, the proposed structure is a double glazed window with potential application for smart, secure, and energy‐saving buildings. Also, practical considerations regarding the deployment of FSS on window glass and the separation distance between the glass layers have been investigated. A prototype of the proposed design is fabricated and measured that a good agreement between measurement and simulation is demonstrated. Therefore, parametric circuit model analysis, deployment of transparent substrate, thin metallic parts on one layer, secure indoor communications, and energy‐saving are some of the advantages of the proposed window.