A category of new microstrip patch antennas with very low profile, wide bandwidth and, most importantly, vertical polarization are developed. A monopolar microstrip circular patch antenna that has a monopole like radiation pattern is proposed. The monopolar patch antenna can produce a conical radiation pattern in the elevation pattern and an omnidirectional pattern in the horizontal plane, like a monopole antenna. The monopolar circular patch antenna has a potential to replace the conventional monopole antenna for the circumstances that require an antenna with very low profile and vertical polarization. A microstrip rectangular patch antenna with high gain and vertically polarized radiation at endfires is also presented. The rectangular patch antenna produces a monopole like radiation pattern in the main elevation plane and an “8”-shaped radiation pattern in the horizontal plane. Furthermore, a microstrip magnetic dipole Yagi antenna with an even higher gain and a high front to back ratio is presented. The Yagi antenna produces a main beam radiating very close to forward endfire and a vertical polarization at the endfire.
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