Analysis and design of double negative metamaterial offering seven operating bands with minimum frequency ratio

A novel plus (+) shaped metamaterial's (MTM) unit cell is introduced and investigated, which exhibits double negative (DNG) characteristics at seven different frequency bands of a minimal frequency ratio of 1.0953:1. DNG characteristics at seven bands are achieved in a dielectric substrate of dielectric constant 4.4. The permittivity (epsilon), permeability (mu) and refractive index n of the proposed MTM are extracted. Furthermore, circuit modeling of the introduced MTM is executed through transmission line theory and an equivalent circuit model (ECM) is realized for its theoretical analysis. The developed ECM is put through Keysight ADS (TM) software to verify the theoretical results. Dispersion equations of the invented MTM are also established, which figure out the zeroth-order frequency at its dominant mode. Simulation analysis is accomplished through Ansys HFSS (TM) software and both the theoretical and simulated results are verified by measured results of fabricated prototype.