Design of Planar CPW-Fed UWB Trapezoidal Monopole Antennas with Band Rejection Characteristics

Planar CPW-Fed trapezoidal monopole antennas with single and dual band rejection characteristics are presented in this study. These antennas can be used to remove interfering frequencies from wireless communication systems such as military services and WiMAX networks at 3 GHz and 3.5 GHz respectively. The antenna prototypes were assembled on single layer FR4 substrate with
$\varepsilon_r=4.35$
occupying small surfaces of 50 mm
$\mathrm{x}58$
mm and U-shaped slots were utilized, and VSWR of 2:1 in the frequency band of 1.6 - 3.8 GHz and notch mismatches up to 10:1 while maintaining omni-directional patterns in the H-plane were satisfied. Moreover, measurement results using the Keysight Fieldfox N9915A Vector Network Analyzer (VNA) are compared with theoretical study of the antennas.