Ultra-Wide Band Microstrip patch antenna for Microwave Imaging

In this work, we propose an ultra-wideband microstrip patch antenna with an improved design for the 3.08 - 10.63 GHz frequency band. This spectrum is allocated to Ultra-Widband by the FCC (Federal Communications Commission) for biomedical applications. The antenna is built on an FR4 type substrate characterised by a dielectric permittivity of 4.3, a loss tangent of 0.025 and thickness of 1.58 mm. this antenna is supplied via a 50 ohm microstrip line with dimensions of 28x30 $\mathbf{m m}^{2}$. We exploit the techniques of miniaturisation over the length of the ground plane to obtain good results in terms of the reflection coefficient, bandwidth and other parameters that characterise the antenna studied. To this end, we used apertures on the patch to ensure that the bandwidth was well matched over the 3.1 GHz -10.6 GHz frequency band. this techniques also enhances the antenna’s gain and efficiency. According to the simulation results, the efficiency is greater than 70% over the entire bandwidth and reaches a maximum value of 86.41% at 7 GHz. In addition, the maximum gain reaches a value of 5.4 dBi at 9.27 GHz. The analysis of this structure was carried out with the CST STUDIO SUITE simulation software. This antenna is intended for a system for detecting cancerous tumours using microwave imaging.