A Low Profile, UWB Circular Patch Antenna with Monopole-Like Radiation Characteristics

a simple ultra-wideband antenna with monopolelike radiation pattern is presented in this paper. The structure of this low profile antenna with height of the 7 mm (0.65 ;
_min
) is based on annular-ring circular patch. To improve the antenna's bandwidth, the main annular-ring circular patch is loaded with two concentric rings and two rectangular slots. The result shows the antenna achieves a 10 dB return loss bandwidth from 2.85 GHz to 8.6 GHz. The monopole-like radiation pattern is maintained throughout the frequency bands by combining four propagation modes of TM
₀₁
, TM
₀₂
, and TM
₀₃
.