Gain Enhancement of Diversity Slot Antenna Using FSS with Metamaterial Unit Cells for UWB Systems

This study represents the design of a dual-port/diversity antenna with enhanced gain property ultra-wideband (UWB) systems. It contains a small-size open-ended slot resonator fed by a pair of semi-arc feed-lines providing radiation/polarization diversity function. An FR-4 dielectric with a thickness of 1.6 mm is employed as the design dielectric. To improve the gain characteristic a 10x10 frequency-selective-surface (FSS) is used below the dual-port UWB slot resonator operating at 3.2-10.8 GHz. The deployed unit cell is containing a square-ring radiator with a diamond-ring strip inside it. 8-9.2 dBi maximum gain level with low variation and almost constant values are observed over the desired band. The main parameters of the design in terms of scattering parameters, gain and efficiency levels were investigated with/without the FSS, and sufficient results are observed. Therefore, it can be used in high-gain UWB communications.