Negative Permeability-Based Electrically Small Antennas

The goal of this letter is to present the behavior of mu-negative (MNG) metamaterial-based electrically small antennas. The Green´s function analysis is applied to characterize the performance of a hemispherical negative permeability (MNG) resonator excited by a slot aperture. The method of moment (MoM) is used to obtain the current distribution over the source excitation. It is illustrated how a resonator composed of negative permeability medium can successfully establish a small antenna element. For small-size structure , the approximated-form Green´s function demonstrates the relation between the resonant frequencies and the material parameters. The obtained results are integrated into the design of a MNG slab radiator. The radiation performance of a slab resonator is detailed using a finite difference time domain (FDTD) full wave analysis. The obtained observations may provide road maps for the future design of metamaterial-based subwavelength antennas.