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

This letter presents a new circularly polarized (CP) phased array antenna (PAA) based on wide heterogeneous beam elements (HBEs) to achieve wide-angle scanning for the first time. The proposed HBEs PAA consists of two elements on each side with inclined beams and six elements in between with broadside beams. A 5 GHz CP HBE antenna with a wide beam width is designed, whose beam can be tilted up to +/- 55 degrees by loading a parasitic director. Then, based on it, a 1 x 8-element HBE PAA is designed, fabricated, and measured, demonstrating a 3 dB gain fluctuation and a 3 dB axial ratio scanning range from -84 degrees to +82 degrees. The peak side lobe level of the HBE PAA is better than -8.8 dB. To the authors' knowledge, the proposed PAA shows the widest scanning range compared with the former linear CP PAAs with similar elements.