Simple bandwidth-enhancement technique for miniaturised low-profile UWB antenna design

Proposed is a simple technique to enhance the bandwidth of a planar monopole antenna with overall dimensions of 30 × 10 mm2. With the proposed method, based on a modified ground plane and a loop feeding structure, the −6 dB bandwidth can be enhanced by ∼50% compared to the basic structure. Based on the simulation results, the antenna achieved a total efficiency higher than 70% on the entire band and the maximum realised gain varied between 2 and 4.8 dB. A prototype has been realised, and good agreement has been obtained between the measured and simulated results.