Two directional UWB monopole antennas are proposed. It is shown that a design methodology for omnidirectional UWB rectangular planar monopole antennas can be applied for directional ones. The directional features are taken by introducing a slanting angle between the radiator and the ground plane. The slanting angle also plays a role in the low cutoff frequency, and it is considered in a proposed equation to determine that frequency. For the two UWB antennas the radiators have a rectangular shape, and the bandwidth is extended by choosing beveling angle and an appropriate height-width ratio. The developed antennas have a bandwidth wider than 10 GHz for a reflection coefficient lower than -10 dB. The directional radiation pattern has an average gain of 5 dB.
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