Design of a Novel 3D-HexaMTM UnitCell for IoT Applications

This paper presents a 3D-hexagonal metamaterial (3D-HexaMTM) unitcell designed for wireless applications. The proposed structure operates at 2.45 GHz in the ISM band and consists of dual hexagonal split-ring resonators (SRRs), metal vias, and a coupling gap. One hexagonal SRR is etched on the backside of the substrate, while the other is positioned above the substrate, separated by a coupling gap, with metal-line vias interconnecting the two structures. The designed unitcell exhibits double negative properties (DNG), characterized by negative permittivity (ϵr) and negative permeability (µr), resulting in a high negative refractive index (n). Electromagnetic simulations using HFSS demonstrate strong resonance behavior, confirming the high negative refractive index, which effectively reduces surface losses. The compact design, with an effective medium ratio (EMR) of 12.12, ensures significant impedance matching and gain enhancement. This unitcell will be used as an array, used as a superstrate, significantly improving impedance matching and gain, making it promising for wireless applications.