Design of low profile wideband omni-directional antenna

A flush-disc antenna with a low profile is proposed in this paper. It can get nearly omni-directional radiation patterns and operate over a wide frequency range. The direction of maximum radiation is at 45°. By adding slots and conducting pins on the radiating aperture, the antenna can achieve a wide bandwidth with a low profile structure. The antenna covers a bandwidth from 2.5 to 4.0 GHz. The VSWR is less than 2 and the gain is up to -2dBi. The design and simulation of antenna are carried out by using the software Ansoft HFSS and a prototype of the antenna is developed and measured. The results of measurement are in good agreement with the simulations. The antenna will be useful for applications in satellite communications telemetry, tracking and command (TTC), and terrestrial mobile communication systems.