Miniaturized Patch Antenna With Grounded Strips

A miniaturized patch antenna loaded with grounded strips is proposed. Two grounded strips, which are connected to the ground plane by an array of shorting pins, are symmetrically positioned underneath the radiating edges of an aperture-coupled patch. With the capacitance provided by the grounded strip and the radiating patch as well as the inductance introduced by the shorting pins, the resonant length of the loaded radiating patch is significantly reduced by 74% compared to that of the unloaded one. The antenna prototype with a patch size of 0 098 lambda(0) x 0.192 lambda(0) exhibits a measured impedance bandwidth of 1.6% centered at 2.62 GHz, a maximum realized gain of 3.9 dBi, and symmetric radiation patterns with the broadside cross-polarization levels of -20 dB in H-plane and -17.5 dB in E-plane. A transmission-line model is presented to explain the operating mechanism of the proposed antenna while parametric studies are carried out to provide the information for the design of the antenna.