Design of dual director short back fire antenna for UWB applicatios

The design proposed in this paper is dedicated to increasing the gain of Short Back Fire Antenna (SBFA) in the 20% bandwidth. A SBFA consists of a round disc of two wavelengths diameter with a quarter wavelength rim. A dipole (or crossed simple) is mounted above the disc with quarter wavelength and a second small disc (disc 1) having half a wavelength diameter is located above the lower disc with a half wavelength. This modified version has a conical reflector with a rim, as well as an additional front disc of more than 15dB and the return loss will be less than -10dB. The designed antenna has a simple and compact construction and high mechanical and electrical characteristic. Hence, it is appropriate for the applications of Ultra Wide Band (UWB) and satellite communications. This proposed antenna presents the input impedance, radiation patterns return loss, VSWR, E-field, H-field current distributions using CST Microwave Studio Software.