A compact ultrawideband monopole antenna with tapered CPW Feed and slot stubs

This paper presents a compact ultrawideband monopole antenna with tapered CPW feed and slot stubs. The proposed antenna is not only very small but also easy to fabricate. Both element feed and ground planes have been designed to be gradual curvatures for achievement of ultrawide impedance bandwidth. The impedance matching has been also improved by inserting two slot stubs at the central feed line. The results show the impedance bandwidth from 2.85 to over 15 GHz and the pattern bandwidth from 3.1 to 9 GHz. The linear phase and small variation of group delay time lower than ±6 nanoseconds have been also obtained. Therefore, this antenna is a good candidate for many UWB applications.