Miniaturization of Circular Patch Antennas Using MNG Metamaterials

Miniaturized circular patch antennas loaded by helices, which operate as μ-negative (MNG) metamaterials, is reported. Two antennas having different helix parameters have been fabricated. The patch radius for both antennas is 42 mm. The first fabricated antenna shows a resonance at 1.126 GHz, which corresponds to a 40% size reduction. The second antenna has an even better size reduction of 60%. Measured results of return loss and radiation pattern at the subwavelength resonances are compared to these parameters at the conventional resonance of the patch antenna.