Aperture-Coupled-Fed Dual-Mode High-Gain and Wideband Microstrip Patch Antenna

A Dual-Mode High-Gain Microstrip Patch Antenna with aperture-coupled feeding is proposed in this paper. By adding four small patches around the central patch, the antenna is able to operate in two modes TM<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">30</inf> and TM<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">32</inf> so that to achieve greater gain. The measurement results show the antenna achieves a bandwidth of about $\mathbf{1 3. 6 \%}$ in fraction or 24.6-28.2 GHz under $\left|\mathrm{S}_{11}\right|{\lt}-10 \mathrm{~dB}$, and the realized gain as high as 13.2 dBi.