Dielectric fortification for wide-beamwidth patch arrays

This paper describes a general methodology for the design of wide beamwidth dual-polarized radiating patches. The half power beamwidth (HPBW) of a patch can be broadened by use of metallic boundaries surrounding the near-field of the patch. However, the use of metallic boundaries also reduces the overall frequency bandwidth of the radiator. This paper proposes dielectric fortification as an alternative approach for the beamwidth broadening of a dual-polarized patch antenna. It is demonstrated that significant broadening of pattern beamwidth is possible by incorporating a relatively thin layer of dielectric walls surrounding the radiator. A desirable broad beamwidth can be handily achieved by use of appropriate thicknesses of the dielectric walls. The effect can be further enhanced by incorporating metallic backing at the outside surfaces of the walls. This technique allows beam broadening without significant degradation in either the cross-polarized radiation pattern, or frequency bandwidth.