Circularly Polarized Wide-Angle Scanning Phased Array Based on Heterogeneous Beam Elements

A circularly polarized (CP) phased array antennas (PAA) based on wide heterogeneous beam elements (HBEs) is presented to realize wide-angle scanning for the first time. The proposed HBEs PAA is formed by two elements at two sides with inclined beams and two elements between two sides elements with broadside beams. A 5-GHz CP HBE antenna with wide beamwidth is designed, whose beam can be inclined up to 50° by loading a parasitic director. Then, based on it, a
$\mathbf{1}\times \mathbf{4}-\mathbf{element}$
HBE PAA is designed, fabricated, and measured, whose 3-dB gain fluctuation and 3-dB axial ratio scanning range reaches
$\pm \mathbf{80}^{\circ}\ (\pm \mathbf{14}^{\circ}$
wider than its standard counterpart) with 8.3 dBi broadsides scanning gain (1.2dB lower than its standard counterpart). To the authors' best knowledge, compared with the former linear CP PAA with similar amount of elements, the proposed design shows the widest scanning range.