抄録
This paper presents a broadband circularly polarized microstrip patch antenna using a circular artificial ground structure (AGS). This antenna consists of a radiating square patch with truncated corners, a modified circular AGS including non-uniform unit cells along the circumference of a circle and a circular ground plane. The proposed antenna radiates right-handed circular polarization (RHCP) with broadband CP characteristics achieved by reflected wave from AGS and radiated wave from the patch. The obtained -10-dB |S11| and 3-dB axial ratio bandwidths are 65% and 37%, respectively.