Compact CPW-fed rotated square-shaped patch slot antenna with band-notched function for UWB applications

A novel coplanar waveguide (CPW)-fed slot antenna with bandstop characteristics is presented for ultra-wideband (UWB) applications. The proposed antenna consists of a rotated square-shaped patch and a 50 Omega CPW feed line. By embedding an inverted V-shaped slot with folded ends, the band rejection property is achieved. Also, etching two slots on the ground plane leads to an improvement in impedance bandwidth. The proposed antenna covers the frequency range of 3.04-20.22 GHz for VSWR < 2, and rejects 5-6 GHz. The total size of the antenna is 20 x 18 x 1.6mm(3), which is smaller than many of the designed slot antennas and covers wider bandwidth. For the fabricated antenna, an omnidirectional pattern is observed over the whole UWB frequency range.