Design of Ferrite–Graphene-Based Thin Broadband Radar Wave Absorber for Stealth Application

Currently, a wide range of materials are used for radar wave absorption. But it is still a very challenging task to develop a thin radar wave absorber that operates for a wide range of frequencies. The main objective of this paper was to achieve good absorption with wide bandwidth corresponding to reflection loss (RL) ≤-10 dB for lower thickness (≤2 mm) by developing ferrite-graphene (FG) composites. A critical study has been carried out by varying the composition of FG to obtain wideband absorption with lower thickness. The effective complex dielectric permittivity (ε\´, ε") and effective complex magnetic permeability (μ\´, μ") of composites were measured using transmission/reflection waveguide method in the range of 8.2-12.4 GHz. These measured ε\´, ε", μ\´, and μ" values have been used for the design of singleand double-layer absorber. Increasing the graphene content in FG composites resulted in a reduction of thickness and wide absorption bandwidth. Furthermore, a multilayer approach is adopted to enhance the radar wave absorption with broad bandwidth at a lower absorber layer thickness. The double-layer absorber shows a strong RL of -55.28 dB at 10.2 GHz with broad bandwidth of 3.1 GHz in the frequency range of 8.6-11.7 GHz. The multilayering approach facilitated to attain a lower absorber layer thickness of 1.7 mm. Findings provide an effective and feasible way to develop a thin and broadband absorber, which may be utilized for stealth applications.