Dual-band circularly polarized antenna with CPW feeding structure

A new design of a dual-band circularly polarized antenna is introduced. The introduced antenna consists of a rectangular patch surrounded by a circular ground with additional two circles, one located above the radiating patch and the other on lower right side, result in both right hand and left hand circular polarized radiation. The antenna operates in two bands 3.3 GHz and 4.8 GHz. The first band is used in WiMax applications. The second band is used in some WLAN applications, it also works in WiMax applications. The antenna is compact in size with overall dimensions 40 mm × 40 mm . The antenna has a low profile and printed on a single side of the substrate. The feeding structure is a 50 Ω CPW. The antenna is RHCP and LHCP at 3.3 GHz and 4.8 GHz, respectively. The antenna is fabricated on FR4 substrate and the results of the return loss are measured and are in a good agreement with the simulated results.