Triple-Mode Wideband Patch Antenna with Enhanced Gain and Omnidirectional Radiation

A low-profile, wideband and high-gain patch antenna based on triple-mode resonance is proposed in this paper. By combining the TM<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">01,</inf> TM<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">02,</inf> and TM<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">03</inf> modes of the circular patch antenna, omnidirectional radiation characteristics are achieved over a wide bandwidth. Two groups of shorting pins are used to adjust the resonant frequencies of the TM on modes to achieve wideband performance. Additionally, the inductive effect of the shorting pins increases the resonant frequencies of the patch, resulting in a larger antenna size at a given frequency and improved antenna gain. The proposed antenna achieves a wide bandwidth of 4.06-4.66 GHz and an enhanced gain of 7.1-8.2 dBi, with a low profile of only 0.043 times the free-space wavelength. It also demonstrates excellent omnidirectionality in the azimuth plane and low cross-polarization levels.