Miniaturized fractal reflectarray element using fixed-size patch

A Minkowski fractal-shaped patch is proposed for thedesign of a reduced-size reflectarray element. The intrinsic miniaturizationcapability of the fractal geometry is fully exploited byleaving unchanged the patch length, while using the fractal scalingfactor to obtain a good reflectarray phase agility. The achieved sizereduction effect allows to choose array grids with smaller interelementspacing, thus offering the opportunity to have wide-anglescanning capabilities. As validation test, a fractal-shaped X-bandreflectarray element, embedded into a 0.3 lambda x 0.3 lambda cell, is designedto give a high phase agility range, greater than 300 . Furthermore,the design and the experimental validation of a 15 x 15 reflectarrayprototype are presented to prove the fixed-beam large anglepointing ability.