Two novel very small monopole antennas having frequency band notch function using DGS for UWB application
In this article, we describe two novel types of coplanar wave-guide (CPW) fed monopole and an asymmetric coplanar strip (ACS) fed half monopole UWB antennas to cover the ultra-wideband frequency operation. The proposed antennas consist of a hexagonal shaped patch with small volume ( 18.4  21.5  1 mm 3 ) and ( 11.4  21.5  1 mm 3 ), respectively. The band-rejection operation achieve at the WLAN (5.155.85GHz) band by adding defected ground structure (DGS) or slit in the ground plane. The antennas are fabricated on FR4 substrate with a relative dielectric constant of 4.4 and thickness of 1mm which are fed by a 50 ? line. The antennas are investigated numerically and experimentally for their impedance matching properties, frequency notched characteristics, and radiation performances. The measured frequency response shows an impedance bandwidth of 13GHz or 130% over 316GHz for VSWR <2 < 2 .
monopole antennas frequency band notch asymmetric coplanar strip (acs) feed coplanar wave-guide (cpw) feed