Multi-band DNG metamaterials: A design approach using combined split ring and triple T-resonators

In this research, a double negative (DNG) metamaterial is proposed for C, X, and Ku frequency bands applications. The two−layer DNG metamaterial comprises of a copper resonator patch and a FR−4 substrate material with a thickness of 1.6 mm. The novel unit cell structure consists of a triple T−shaped resonator within the square split-ring resonators (SRR). The proposed metamaterial exhibits negative permittivity and permeability for multi-band operation which provides more control of electromagnetic waves for multi-band operation. The presented design resonates at four resonance frequencies of 4.65 GHz, 9.08 GHz, 11.02 GHz, and 12.03 GHz, which is validated through simulations in the CST Microwave Studio and measurements of the fabricated DNG metamaterial. The detailed parametric analysis of the effects of geometric modifications on the S-parameters is presented. An effective medium ratio (EMR) of 6.4 confirms the potential of the proposed metamaterial for practical use, such as in telecommunications, radars, and antennas for achieving advancements in miniaturization, performance improvement, absorption efficiency, radar signature enhancement etc.