Super-Directive, Efficient, Electrically Small, Low-Profile Antenna based on Compact Metamaterial
Abstract
Artificial Magnetic Conductors (AMC) present an attractive substrate for low profile antennas which can take advantage of intrinsic zero reflection phase response to boost antenna performance without the need for thick quarter wave backplane. In this paper, a modified version of the Egyptian Axe Near-Field-Resonant-Parasitic (NFRP) dipole antenna is placed over compact AMC based on square spiral metallic patches and a capacitor network beneath the ground plane. Simulation results demonstrate that the NFRP antenna is electrically small (ka(1)=0.498) with a low-profile (total height = 0.07 lambda(0)) when placed over compact AMC (ka(2)=1.29). It achieves super-directivity (6.52 dBi), high realized gain (5.7 dBi) and high radiation efficiency (83.7%).