Numerical Investigation of a Circular Enclosed Square Split Ring Resonator-Based Metamaterial for Gain Enhancement in Multiband Satellite Antennas

In light of recent advances in the field of metamaterials, this research examines the electromagnetic performance of a Circle enclosed Square Split Ring Resonator (Ces-SRR) based negative permittivity metamaterial, designed with an electric physical size of 0.079λ × 0.079λ and assembled on a slab of Rogers RO4350B substrate. The numerical analysis using CST revealed that the proposed metamaterial displays a triple band resonance frequency at 2.97, 6.98, and 9.68 GHz, collectively covering the S-, C-, and X-bands. The negative electric permittivity response was obtained across three distinct frequency regions: 2.93-3.023 GHz, 5.33-7.3 GHz, and 8.31-9.68 GHz, along with near-zero magnetic permeability at the resonance frequencies. The Effective Metamaterial Ratio (EMR) of the unit cell is calculated to be 12.63 at 2.93 GHz, indicating the compactness of the structure. The simulation results and metamaterial design were validated using other Maxwell equations solvers, HFSS and COMSOL MultiPhysics, showing good agreement between both software packages and attesting the reliability of the proposed material. With these leading advantages, the presented metamaterial structure is suitable for enhancing emerging satellite communications and radar applications. Further investigation of a Log-Periodic Dipole Array (LPDA) antenna using CST Microwave Studio software indicates that the metamaterial-modified LPDA outperforms the regular LPDA antenna in terms of gain particularly at regions where the electric permittivity is negative.