A Triple-Band Ultrathin Metamaterial Absorber With Wide-Angle and Polarization Stability

This letter presents a triple-band compact and efficient ultrathin metamaterial absorber with wide-angle and polarization stability. The compact single unit cell includes a metallic background plane, four groups of dipoles lying around a metallic ring connected by four groups of pins, and only 1-mm low-cost dielectric layer. In addition, the main parameters of the designed absorber are investigated and optimized to show that each of three absorption frequency points can be effectively separately adapted, respectively. The simulation results demonstrate that this absorber has good absorption rates and polarization-insensitive characteristic over wide angles of incident waves for both transverse electric (TE) and transverse magnetic (TM) in three frequency bands. The waveguide measurement method is utilized to test the simulated results of three good absorption peaks.