In this paper, one 3×3 and one 5×5 antenna arrays are studied. In each array, one probe-fed circularly polarized (CP) microstrip patch antenna is placed at the center as the driven antenna and is gapped coupled to the remaining elements. It is investigated that CP performance of the patch can be proved by properly arranging these parasitic elements. The driven patch is a perturbed square one with two diagonal corners truncated. The remaining elements are square patches slightly smaller than the driven patch. The proposed antennas have been constructed and measured. The 3×3 array has a measured gain of 7.7 dBic with a 3 dB axial ratio bandwidth of 3.3%. The 5×5 array has a measured gain of 9.3 dBic with a 3dB axial ratio bandwidth of 8.1%.
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