Design of U-shaped feed structured antenna for ultrawideband application

In this paper, a new compact suspended antenna is presented for ultrawideband (UWB) application. In the proposed design, a new unequal arm U-shaped feeding patch is suspended below an H-shaped radiating patch to produce wide bandwidth through the electromagnetical coupling technique. This new U-shaped feeding patch is connected to a probe to compensate for probe inductance. Two shorting strips are introduced to hold the radiating patch above the ground plane, as well as reduce the antenna’s size. These strips improve the bandwidth at the lower operating band. The proposed antenna has a compact dimension of \(0.129\lambda \times 0.186 \lambda \times 0.096 \lambda \), where \(\lambda \) is the wavelength of the lowest operating frequency. The proposed antenna has been optimized and its parametric study is performed using an electromagnetic field simulator, based on the finite element method. The proposed antenna is prototyped and measured. Measured results indicated that the proposed antenna structure has achieved an impedance bandwidth of 103.86 %, ranging from 4.3 to 13.59 GHz at \(\hbox {VSWR}\le 2\). The measured results of the wideband and stable radiation patterns with acceptable gain signify the effectiveness of the proposed antenna configuration in the context of UWB application.