Design and characteristic mode analysis of a wideband high permittivity patch antenna

A wideband patch antenna is designed for a substrate with relative permittivity 9.8 and loss tangent 0.002. Impedance and axial ratio bandwidths exceeding 69% are achieved. The design is investigated using characteristic mode analysis to determine the modal resonances responsible for its wideband behavior. The results show that the lowest-order patch modes are broadband, and that probe and substrate resonances limit the upper operating frequency of the antenna more significantly than higher-order resonances of the conducting patch.