U-shaped microstrip patch antenna with novel parasitic tuning stubs for ultra wideband applications

In this study, a novel compact microstrip antenna with an ultra wide bandwidth is presented. The proposed antenna is a U-shaped square patch combined with two parasitic tuning stubs which is fed by a coplanar waveguide (CPW). The total size of the fabricated antenna is 24 × 28 × 0.787 × mm³. The dimensional parameters for the antenna are introduced and their effects on the frequency characteristic have been investigated through a parametric study. Simulated and experimental results indicate that the antenna achieved an ultra wideband impedance bandwidth (S₁₁ <; -10 dB) as high as 129%. The radiation patterns of the antenna are measured and presented. The simulated results show good agreement with the measured results. The measured gains range from 1.6 to 5.3 dBi against frequency. These characteristics make the antenna suitable for UWB applications.