Circularly Polarized Slot Antenna Dual-Fed with Microstrip Lines

Abstract

A novel circularly polarized slot antenna is presented in this paper. The proposed antenna consists of a radiating slot etched in a metal layer placed on one side of a dielectric substrate and a dual feed microstrip network placed on the other side. Both modes of the radiating slot are excited via electromagnetic coupling through the substrate. The size of the new antenna, which is optimized for operation at 5.2 GHz, is 2.9 cm -by- 2.6 cm excluding the surrounding ground plane. The proposed antenna is characterized both theoretically and experimentally. The results show that it enjoys several advantages such as wide impedance bandwidth (43%), wide axial ratio bandwidth (8.65%), low cross polarization level (less than -10 dB), and high radiation efficiency (95.61%). © 2008 VSP.