Targeted design, analysis and experimental characterization of flexible microwave absorber for window application

Abstract

Microwave absorber for window application is systematically studied to eliminate eletromagnetic pollution. Lossy “wheel-like” metasurface is proposed for wideband absorption. Origin of dissipation, loss features and contributions of each part in the absorber are analyzed thoroughly to reveal the absorption mechanisms. Based on the electromagnetic responses, an equivalent circuit model is established and analyzed as a practical design method for general Window-use Microwave Absorbers (WMAs). Using the method, design feasibility of WMAs can be anticipated. WMAs with adjustable single-band, dual-band or broadband absorptions can be effectively realized. Evidenced by experimental measurements, the large-scale WMA can achieve 90% absorption in 6–16.5 GHz, which is in great agreement with simulated results. In addition, the WMA can also maintain high absorption regardless of incident angles. Even through it is bent into curvature, the flexible WMA can still operate well in a wide band, which indicates the WMA is promising for applications in nonplanar situations. Evaluated in imitating usage scenario, efficiency of dye-sensitized solar cell (DSSC) decreases only a little after having the WMA put on because of its high optical transparency. The WMA has advanced comprehensive performances. The equivalent circuit model is also proved of high reliability. Keywords: Microwave absorber, Design method, Window material, Wideband, Flexible