Double-Split Rectangular Dual-Ring DNG Metamaterial for 5G Millimeter Wave Applications

This article presents the design and analysis of a low profile double-negative (DNG) metamaterial unit structure for 5G mmWave (millimeter wave) applications. The structure, comprised of double-slotted rectangular ring patches, experiences the peak current value near the magnetic resonance, causing the metamaterial to resonate at 28 GHz where it exhibits negative effective permittivity and permeability. The 3.05 mm x 2.85 mm compact structure is designed over a substrate Rogers RT/Duroid 5880 to attain better effective medium ratio (EMR) in the 5G frequency range (27.1-29.2 GHz). A rigorous parametric study is conducted to obtain the proposed design. Full-wave electromagnetic simulation software tools CST and HFSS are used to generate the scattering parameters for the analysis. The Nicolson-Ross-Wier method is used to observe the negative effective permittivity and permeability. In addition, different output quantities, e.g., surface current and electric and magnetic field distribution, are investigated. The structure is further tested with 1 x 2, 2 x 2, and 4 x 4 arrays, where the results show adequate agreement to be considered for 5G mmWave applications.