A transparent and flexible microwave absorber covering the whole WiFi waveband

Abstract

The WiFi technology has become a world-wide everyday service, and the accompanying electromagnetic pollution has attracted more and more attentions. This paper presents a transparent and flexible broadband metamaterial absorber (MMA) covering the whole WiFi waveband. The transparent and conducting material Indium Tin Oxide (ITO) was used for both the frequency select surface and the backplane ground layer, and polydimethylsiloxane (PDMS) was used as the dielectric layer for the microwave MMA. The absorber featured >80% absorption covering a wide frequency range of (2.2-5.85) GHz, which includes all the frequency bands of WiFi signal. The absorber was insensitive to the polarization angles and dropped little for incident angles less than 30°. Signal shielding experiments in 2.4 GHz and 5 GHz were carried out to demonstrate the application potential of the absorber. With additional advantages of optical transparency and mechanical flexibility, the broadband MMA can be useful in WiFi related applications in the future.