Low-Profile Patch Antennas with Loading of Shorting Pins for Improved Functionalities: Invited Paper

This paper presents a brief review on functionality-improved patch antennas with loading shorting pins that are recently proposed by the authors' group. Firstly, shorting pins can increase (reduce) the feeding current (voltage) of a patch antenna, so the edge-fed impedance can be reduced. Meanwhile, the cross-polarization can be kept in low level when the shorting pins are symmetrically loaded. Secondly, the shunt inductive effect of shorting pins significantly increases the resonant frequency of fundamental mode, resulting in enlarged radiating area, and so enhanced gain can be obtained. Thirdly, by properly adjusting the electrical size of patch through loading of shorting pins, the two orthogonal far-field components will have close beamwidth and beam shape, and then wide axial-ratio beamwidth (ARBW) can be realized.