A Novel Wideband Shorted-Patch Antenna with A π—Shaped Slot Under Three Resonant Modes

In this paper, a novel wideband shorted-patch antenna with a π-shaped slot under three resonant modes is proposed. A horizontal rectangular slot is introduced on the shorted patch to excite two odd modes with close frequency points, the initial shorted patch resonates at TM30 mode and the larger patch without shorting wall connected, which created by the horizontal rectangular slot operates at TM10 mode. Furthermore, two symmetrical vertical rectangular slots are cut on the larger patch to reduce the frequency of TM12mode of larger patch, and the three rectangular slots form a π-shaped slot. Moreover, a semicircular ring slot is used to achieve a good impedance matching. Based on the arrangements above, a wideband shorted-patch antenna can finally be realized. The simulation results show that the impedance bandwidth of proposed shorted-patch antenna for [S11] < −10 dB is extended to 42.8% at the profile of 0.067 free-space wavelength. Additionally, the proposed antenna maintains a stable radiation pattern over the operating band.