UWB fractal slot antenna designs

The allocation of 3.1-10.6 GHz spectrum by Federal Communications Commission (FCC) for Ultra Wideband (UWB) radio applications has presented a myriad of exciting opportunities and challenges for design in the communications arena, including antenna design. The challenge of designing compact antennas with operating bandwidths of more than 100% can be met by using wide slot antennas with fractal boundaries. In this paper, two fractal slot antenna designs based upon Koch Snowflake geometry and Sierpinski gasket are presented which have good radiation efficiency over the UWB frequency range. Coplanar waveguide feeds with tuning U-stubs have been used to achieve the desired bandwidth. Optimization of antenna geometries has been carried out with HFSS simulations. The resulting geometry is compact and the measured results compare well with the simulation data.