A Novel Compact Ultrawideband Antenna

In this paper, novel compact ultrawideband (UWB) antennas are proposed and successfully demonstrated within the bandwidth with the ratio of the maximum and minimum frequency to be more than 30. The results from electromagnetics (EM) simulation and measurement show good agreement. From the EM simulation results, the electromagnetic wave could be radiated to the free space through the antenna only if the antenna impedance were matched to one of its feed systems within the bandwidth. The developed antenna with a small size of 17 $\times$ 17 $\times $ 12 mm$^{3}$ shows voltage standing wave ratio (VSWR) of less than 2.5 : 1 from 3 to 100 GHz for the simulated data, and less than 2 : 1 from 3 to 50 GHz for the measured data. The gain of the developed antenna is more than 2 dBi from 3.1 to 10.6 GHz in the application of high-speed wireless digital communication system.