Design of a dual-band metamaterial absorber in WLAN bands with high stability over incidence angle and polarization

A dual-band metamaterial absorber operating at two wireless local area network bands, 2.45 GHz and 5.61 GHz, is designed based on a systematic methodology that involves equivalent circuit model calculations and full-wave electromagnetic simulations. The unit cell of the absorber consists of two kinds of Jerusalem cross resonators, one of which is rotated 45 degrees with respect to the other, on a metal backed lossy dielectric. Interdigitated capacitors are introduced as the capacitive components of one of the Jerusalem cross resonators to reduce the absorption resonance frequency and electrical size. The proposed dual-band metamaterial absorber shows absorption rates of 99.83 % and 98.98% for the lower and upper absorption bands, respectively. Furthermore, it presents a robust performance under oblique incidence angles for both transverse-electric and transverse-magnetic polarizations.