A simple UWB microstrip-fed planar rectangular slot monopole antenna

This paper presents a new printed slot monopole antenna for ultra-wideband applications. The proposed antenna is a rectangular slot excited by a 50 Ω microstrip line. Techniques to expand the impedance bandwidth of a simple rectangular monopole antenna are given. The experimental results show that the presented structure shows an ultra wide impedance bandwidth behaviour based on S₁₁ ≤-10 dB, covering frequency range from 1.82 to 12.59 GHz, 148%. Current density distribution on the antenna was also computed to gain a better insight of its behaviour. The antenna radiation pattern and gain are measured and presented. The measured results are in good agreement with the simulation results. The measured results indicate that the antenna radiation patterns are stably omnidirectional over the entire frequency range of interest. The measured gains range from 2.8 to 6.3 dBi versus operating frequency.