In the present study, an ultra-wideband (UWB) antenna has been proposed using coplanar waveguide (CPW) feed with dual-band-notch characteristics. Slot-loaded radiator and U-shaped CPW resonator are used for band rejection at 3.5 and 5–6 GHz respectively to reduce interference with existing World interoperability for microwave access and wireless local area network systems. With an extended operating band (measured at 10 dB return loss) the antenna operates successfully over the entire UWB range (3.1–10.6 GHz) with a form factor of 30 × 20 × 1.524 mm3 on a commercially low-cost FR-4 substrate. Experimental measurement results are presented in support of the simulated results for the proposed antenna for practical application. The antenna has been successfully fabricated and measured, showing broadband matched impedance and good omnidirectional radiation pattern throughout the operating bandwidth. Measured time-domain analysis for both the orientations, i.e. face-to-face and side-by-side, yields excellent performance in the open environment scenario. With fairly good and consistent monopole such as omnidirectional radiation patterns in H-plane and linear transmission responses, the proposed antenna is well suited to be integrated within portable devices.