Abstract

In this paper, a circularly polarized omnidirectional slotted antenna is presented for ISM applications. The proposed antenna made with a feedline in the ground plane, an annular elliptical slot and four rectangular slots etched on radiating patch and semicircular patch slots are used to achieve circular polarization. The ground plane feed line impedance value is 50 ohms. The substrate used here is FR4 and its relative permittivity 4.4 and loss tangent 0.02. Antenna dimensions are 58mm×58mm×1.6mm. The antenna is resonating at 2.45 GHz with return loss of -31.12dB. The impedance bandwidth covers from 2.02 GHz to 2.77 GHz (% B.W is 30.6%). The proposed antenna design and simulation carried out using HFSS Simulator. The antenna show high gain characteristics, omnidirectional radiation pattern, high efficiency, circular polarization and better co and cross polarizations. The proposed antenna can be effectively useful for ISM and WLAN applications.