A Novel Compact Ultra-wideband Rectangular Shaped Antenna

摘要

In this paper, novel Compact Ultra Wideband (UWB) antennas are proposed. It consisted of rectangular shaped patch of Lx = 15 mm by Ly = 14.5 mm dimensions with two circled concave or convex profiles into its two corners. All simulated and measured prototypes are printed on a partial grounded FR4_epoxy substrate of 30 mm by 35 mm dimensions. Both of these inserted geometrical shapes provide different electric lengths with smoothly variations witch are adjusted to enhance the impedance bandwidth and reduce the VSWR between the main resonance frequencies of the rectangular patch. The excitation is launched through a 50 Ω microstrip feed line. Design and performances are analysed using Ansoft HFSS electromagnetic simulator based on the finite element method and measured using a vector network analyser Anritsu 37369C (40 MHz to 40 GHz) where the calibration plane is the SMA connector jack used to connect the antenna. Various prototypes are simulated and measured in order to view the correlation parameter between the impedance bandwidth and the circled convex or concave radius. The best antenna simulated and measured results correspond to a prototype with two convex circled forms of 3mm radius. Nevertheless, the bandwidth is ranging from about 3.55 GHz to 4.6 GHz and from 7.4 GHz to 11.7 GHz for S_(11) < -10 dB.