Design of a Double-layer Miniaturized Metamaterial Absorber in 5G Millimeter-wave Band

A double-layer miniaturized metamaterial absorber based on the indium-tin-oxide (ITO) resistive film in a 5G millimeter-wave band is proposed in this paper. Its core structure is implemented by two layers. The first layer is a glass substrate with ITO resistive film attached, and another ITO is attached to the FR-4 substrate in the second layer. The simulation results reveal that under the conditions of transverse electric or transverse magnetic polarization, the absorption efficiency of the designed structure exceeds 90% in the bandwidth of 23.3GHz ~ 35.2GHz, and reaches the peak of nearly 100% at the resonant point of 28GHz. Further analysis shows that the absorption performance of the incident angle from 0° to 40° can reach more than 90% in the operating frequency, which is relatively stable.