Experimental research on a planar equiangular spiral antenna

The equiangular spiral antenna (EASA) is a kind of wide band antenna with circular polarization. This paper designed and fabricated a practical planar ESA within the discussed frequency of 3GHz to 11GHz. The diameter of the fabricated ESA is 82 millimeters. The height of metal cavity filled with absorber materials is 30 millimeters. The designed ESA was fed by a wide band miniaturized microstrip Balun. The radiation performances of the designed ESA were simulated. The specific experimental results of the fabricated ESA are given, which demonstrate that the ESA has radiation performances of wide beam and approximately circular polarization. The experimental research results in this paper can provide a technical reference for the practical ESA design in wide electronic system applications.