Ultra-Thin UHF Broadband Antenna on a Non-Uniform Aperiodic (NUA) MetaSurface

A new concept to design ultrathin directional broadband antennas using a nonuniform aperiodic metasurface is introduced. The study and design of the NUA metasurface show that, by employing a decreasing taper for both the metasurface patch and their interelement spacing, broad impedance and pattern bandwidths can be attained. Experimental results show that, with a total thickness of 0.04 of the free space wavelength (corresponding to the lowest frequency of operation), an octave bandwidth can be attained, which is significantly larger compared with existing designs on uniform mushroom electromagnetic band-gap structures.