Rotational Symmetric Circular Split-Ring with Inductive Tail-Shaped Microwave Metamaterial Absorber for Aeronautical Radionavigation Applications

In this paper, a rotational symmetric, circular split-ring with an inductive tail-shaped microwave metamaterial absorber was proposed at resonance frequencies of 9.63 GHz, 11.14 GHz, 13.25 GHz, and 15.48 GHz for Aeronautical Radionavigation Applications. It shows an efficient result having single negative (SNG) metamaterial properties and subwavelength properties with maximum absorptions of 99.9%. The proposed design presented a significant improvement in absorption in broad incident angle polarization compared to other relative works. Moreover, the size of the proposed absorber is smaller than that of other works, which provides a good effective medium ratio (EMR) and can be easily placed in electronic devices, mainly in sensors. It is insensitive at wide co- and cross-polarizing angles of incident EM waves because it can absorb EM waves falling at different angles, i.e., 0 to 180 degrees, which benefited the absorber to apply it in other fields as well, like in Biomedical (Hyperthermia), Radar, Satellite (Ku Band), Defense and EMI/EMC reduction, polarization detectors, etc. We also analyzed the absorption with a proper RLC circuit designed on the basis of the surface current while showing absorption in each particular frequency. Further, this research can be expanded in the direction of beamforming with the integration of pin diode into the patch of the metamaterial absorber.