LAUSR

A two-dimensional (2D) high-constitutive parameter (TDHCP) substrate is designed using an artificial metamaterial with high-constitutive parameters. The planar TDHCP substrate is used for miniaturising of a circularly-polarised microstrip patch antenna. A 2D metamaterial unit cell is needed due to the fact that the electric and magnetic vectors are rotating in a circularly-polarised antenna. The proposed TDHCP substrate increases the constitutive parameters of the host substrate. It is composed of periodic split-ring resonators loop circuits embedded in a low dielectric host medium. The TDHCP substrate provides equal permittivity and permeability ( e r ≅ μ r ) at any frequency of interest, which compensates for the bandwidth reduction due to the increased permittivity. The size of the proposed TDHCP substrate antenna at 850 MHz is reduced up to about 72% compared to the conventional microstrip patch antenna. The bandwidth of the antenna is increased compared to high-electric permittivity substrates because of the increased the magnetic permeability. The proposed antenna is fabricated and measured. The simulated and measured results show a good agreement.