Analysis of the radiation properties of a point source on a uniaxially anisotropic meta-substrate and the application to a high-efficiency antenna

The radiation efficiency of a point electric source on a loss-less uniaxially anisotropic meta-substrate is computed by the mixed potential integral equation technique. For this purpose, the multilayered Green´s functions of the structure are derived from the spectral domain transmission line model of the medium. The efficiency of the antenna is compared for different permittivities and permeabilities of the meta-substrate with fixed TE and TM wave numbers. It is shown that at certain frequencies the radiation efficiency is enhanced as the ratio of the permeability over permittivity is increased. This suggests that an antenna on a mushroom type meta-substrate or a meta-substrate which is constructed from the stacked split ring resonators (SRR) in the plane of the substrate may exhibit a high radiation efficiency close to the resonant frequencies of the metallic loops, as compared to a conventional substrate.