Fractal geometries are appealing in all applications where miniaturization capabilities are required, ranging from antennas tofrequency selective surfaces (FSS) design. Recently, some fractal patches configurations, giving low losses, reduced size, andquite good phase ranges, have been proposed for the design of reflectarray unit cells. This paper reviews existing fractal-basedreflectarrays, highlighting their benefits and limitations. Furthermore, a comprehensive analysis of an innovative reflectarray unitcell, using a fractal-shaped fixed-size patch, is presented. The miniaturization capabilities of the Minkowski fractal shape are fullyexploited toobtain a compact cell offeringquite goodphase agility, by leavingunchanged thepatch size andactingonlyonthe fractalscaling factor. Experimental validations are fully discussed on a realized 10GHz 0.3 × 0.3 cell.This is subsequently adopted tosynthesize various reflectarray prototypes offering single or multiple-beam capabilities over a quite large angular region (up to 50degrees). Finally, experimental validations on a realized 15 × 15 elements prototype are presented to demonstrate the wide anglebeam-pointing capabilities as well as a quite large bandwidth of about 6%.
Fractal Reflectarray Antennas: State of Art and New Opportunities
COSTANZO, Sandra;VENNERI, FRANCESCA;DI MASSA G;BORGIA A;
2016-01-01
Abstract
Fractal geometries are appealing in all applications where miniaturization capabilities are required, ranging from antennas tofrequency selective surfaces (FSS) design. Recently, some fractal patches configurations, giving low losses, reduced size, andquite good phase ranges, have been proposed for the design of reflectarray unit cells. This paper reviews existing fractal-basedreflectarrays, highlighting their benefits and limitations. Furthermore, a comprehensive analysis of an innovative reflectarray unitcell, using a fractal-shaped fixed-size patch, is presented. The miniaturization capabilities of the Minkowski fractal shape are fullyexploited toobtain a compact cell offeringquite goodphase agility, by leavingunchanged thepatch size andactingonlyonthe fractalscaling factor. Experimental validations are fully discussed on a realized 10GHz 0.3 × 0.3 cell.This is subsequently adopted tosynthesize various reflectarray prototypes offering single or multiple-beam capabilities over a quite large angular region (up to 50degrees). Finally, experimental validations on a realized 15 × 15 elements prototype are presented to demonstrate the wide anglebeam-pointing capabilities as well as a quite large bandwidth of about 6%.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
