A compact CPW-fed monopole antenna with an U-shaped slot for 5 GHz/6 GHz band-notched ultrawideband applications

A planar ultrawideband (UWB) antenna with an U-shaped slot for a 5/6 GHz band notched characteristics is presented. The antenna is a planar structure and has a compact area of 25 × 25 mm
²
, which covers the frequency band from 3.1 GHz to 10.6 GHz (VSWR ≤ 2 ). The antenna has a circular slot cut in the ground plane and a circular patch is printed within that. A 50-Ω coplanar waveguide (CPW) transmission line is used to feed the printed circular metal patch. By removing a U-shaped slot from the circular patch, band rejected property in the WLAN band is obtained. The compact antenna has the promising performance including broadband impedance matching, consistent radiation pattern and stable gain.