Abstract
In this work, we present the design of a low-profile circularly polarized antenna with a wide beam-width for low-angle coverage. The antenna consists of two parts: a dielectrically loaded short circuited quadrifilar helical antenna locates at the center, with its four ports terminated by 58 ohm impedance each. Additionally, four monopoles with 90 degrees phase progression are placed around the helix, and sections of Archimedean spiral are used to top load the monopoles. The designed antenna has a peak gain of approximately 3dB and its 3dB beam width is 150 degrees. The axial ratio of the antenna is less than 3 in the entire upper hemisphere over a wide frequency band, and its bandwidth is 18%.