Design and measurement of broadband magnetic composite metamaterial absorber with C-band absorption

Abstract

We present the design and measurement of broadband magnetic composite metamaterial absorber with C-Band absorbing effect. The absorber embeds the periodic array of concentric semicircular copper sheet in the FeSiAlp/epoxy composite material layer. The wave-absorbing properties of the FeSiAlp/epoxy resin composite is greatly improved compared with the simple FR4 matrix material, bandwidth with reflectance less than −10 dB increases from 0 GHz to 8.13 GHz. Simultaneously, due to the introduction of the frequency selective surface (FSS) structure, the absorber performance of the absorber is also improved in C-band. The peak of the absorber appears at 7.46 GHz, and the reflectivity reaches −12.78 dB, and the absorption reaches 94.72%. After optimizing the dimensions of FSS, The FeSiAlp/epoxy resin composite absorber with a thickness of 2.6 mm reached peak simultaneously at 7.46 GHz and 16.64 GHz, and peak reflectance reach −12.78 dB and −18.21 dB, respectively, and corresponding absorption reached 95.68% and 99.70%, respectively. Bandwidths with reflectivity less than −10 dB reaches 8.13 GHz, the absorber has obvious absorption effect in C-band. The experiment basically verified the simulation results. Hence, the absorber with special structure design not only overcomes the problem of narrow absorption band of metamaterials, but also solves the shortcoming of weak C-band absorption effect of magnetic material absorber.