Broadband metamaterial microwave absorber based on asymmetric sectional resonator structures

In this paper, we present a novel design of broadband metamaterial microwave absorber (MWA) based on asymmetric sectional resonator structures (SRSs), which has been verified by simulation, calculation based on circuit theory, and experiment. The broadband perfect absorption of the MWA can be obtained by assembling four asymmetric SRSs with different sizes. The numerical results indicate that the bandwidth of the broadband MWA based on asymmetric SRSs is about 16.2 times of the ones based on single SRS or four complete symmetric SRSs. The broadband perfect absorption of the proposed MWA mainly originates from the excitation of the fundamental resonance mode of the SRS. The numerical results also demonstrate that the broadband MWA exhibits an angle-insensitivity microwave absorption capacity, which is manifested as a high absorption level at large incident angles for both transverse electric and transverse magnetic modes. Thus, the proposed broadband MWA turns out to be suitable for a wide variety of potential applications in stealth technology and energy harvesting.