Wideband Circular Polarized Antenna for Satellite Based Navigation Systems

摘要

In this paper we propose a wideband antenna structure to cover the non-military satellite navigation frequency spectrum. The antenna structure consists cross dipole elements fed with 90° phase difference to provide proper axial ratio within the whole frequency band. The axial ratio is improved by using two parasitic elements near to each dipole arm. The dipole arms are designed on a FR4 substrate and placed above a ground plane to reduce the effect of any metallic object behind the antenna. The impedance matching is better than -15 dB in 1-1.7 GHz and axial ratio is better than 3 dB in 1.17-1.67 GHz, covering the required bandwidth for satellite navigation systems.