A multi-band binary radar absorbing metamaterial based on a 3D low-permittivity all-dielectric structure

A new binary-structured metamaterial absorber (MA), consisting of a 3D cross-shaped dielectric (CSD) periodic array and a metal back plane, is proposed and fabricated. This structure realized six resonant absorption peaks below −10dB in the range of 8–18 GHz. Both simulated and experimental results demonstrate the effectiveness of this design in generating multiband and low frequency absorption, which is difficult to achieve in previous 2D dielectric absorbers. The electromagnetic(EM) field and energy loss density distributions of absorption peaks were investigated as well as effects of structural parameters on the reflection loss spectra. It indicated that multimode resonance is generated by standing waves in the 3D dielectric structure. Moreover, since the structure is made of a low-permittivity dielectric resin, the fabrication is relatively easy and low-cost. The design of a three-dimensional low-permittivity all-dielectric structure described in this work has potential applications in the EM energy capture and stealth fields.