Band-notched compact rectangular ring antenna using triple Ω-Shaped structures for UWB systems

In this letter, a new ultra wideband monopole antenna with frequency band-stop function is designed and manufactured. The antenna contains a rectangular ring radiating patch and a partial ground. In the structure, by etching a Ω-shaped slot on the ground plane, extra resonance is excited and therefore more extended impedance bandwidth can be achieved. In order to create band-rejected function, a Ω-shaped sleeve into the rectangular ring patch and an inverted Ω-shaped slot on it and feed-line are used. The measured results depict that the antenna is able to cover the bandwidth from 2.6 to 10.4 GHz for VSWR ≤ 2 excluding the rejected bands from 3.1 to 3.8 GHz and from 5.0 to 6.0 GHz. Acceptable VSWR and radiation pattern characteristics are earned on the frequency band of interest.