All-dielectric radar absorbing array metamaterial based on silicon carbide/carbon foam material

A kind of all-dielectric radar absorbing array metamaterial (AMM) is created by simulation and experiment. The AMM bases on the silicon carbide/carbon (SiC/C) foam dielectric material and the idea of metamaterial (MM) design. The SiC/C foam dielectric material is obtained by replica method. The changing laws of the effect on absorption performances due to the physical dimension and array period of AMM are studied. The electromagnetic (EM) wave absorption mechanisms of AMM are investigated by the EM field distribution, power loss density distribution, impedance analysis and equivalent circuit method. At last, an optimized AMM with excellent absorption properties is designed and prepared. The reflectivity of the optimized AMM below-10dB cover the frequency of 4GHz - 18GHz with the bulk density is about 0.5g/cm(3). The absorption performance of the optimized AMM is determined by using the freespace method. The simulated results are agree well with the measured results. Furthermore, the absorption performance under wide-angle oblique incidence, the mechanical behavior, and the thermal stability of AMM are investigated. The design method proposed in this paper is a kind of effective supplement for constructing lightweight and broadband radar absorbing material, and also useful in the design of other absorbing material. (C) 2018 Elsevier B.V. All rights reserved.