Tuning metallic stub loaded symmetrical resonator based dual band metamaterial absorber for wave shielding from Wi-Fi frequencies.

In this article, a simple metamaterial absorber (MMA) is presented aiming absorption of microwave signals from Wi-Fi frequencies of 2.4 GHz, and 5 GHz. The MMA unit cell constructed on 20 × 20 mm² FR4 substrate provides maximum absorption of 99.2% and 99.9% at 2.4 GHz and 5 GHz with the flexibility of on-design tuning of maximum absorption frequencies. The tuning metallic stubs connected with the outer ring provide the provision of frequency adjustment from 2.34 GHz to 2.45 GHz, whereas middle ring stubs along with the innermost ring assists for frequency tuning from 4.68 GHz to 5.1 GHz. Due to symmetrical structure, excellent angular stability up to 60° is achieved with near zero cross-polarization effect for both transverse electric (TE) and transverse magnetic (TM) modes of excitation. The measured result of the proposed MMA is analyzed that shows good similarity with the simulated one. Due to its simplistic design within nominal dimension, high absorption, flexibility to frequency tuning, wide angular stability, and no cross-polarization effect, this MMA can be a good candidate for absorber applications in wireless communication systems, especially for wave shielding from Wi-Fi frequencies. [ABSTRACT FROM AUTHOR]