Design and simulation of multi-layer GPS antenna with tapered balun feeding with circular polarization and special radiation pattern in order to reduce interference effects

Heidarifard, Hamideh; Fallah, Mohsen; Abbasi Arend, Bijan

Design and simulation of multi-layer GPS antenna with tapered balun feeding with circular polarization and special radiation pattern in order to reduce interference effects

Document Type : Original Article

Authors

Hamideh Heidarifard ¹

Mohsen Fallah ²

Bijan Abbasi Arend ³

¹ PhD student, Malek Ashtar University, Tehran, Iran

² Associate Professor, Malek Ashtar University of Technology, Tehran, Iran

³ Associate Professor, Tarbiat Modares University, Tehran, Iran

Abstract

In this article, the design and simulation of a single-feed antenna with right circular polarization that can be used in GPS applications is presented. But the main feature and what distinguishes this antenna from other single-feed antennas with right-handed polarization used in GPS systems is that due to the minimization of interference effects, this article considers the antenna to introduce the maximum gain-to-gain ratio in horizontal angles (θ=90) at least to 20 dB . To achieve these goals, a multi-layer antenna placed above the ground is proposed. The first layer consists of a metal plate with two corners cut and an oval slot in the middle. The next layer is a circular wire antenna that includes two rectangular rings, and the last layer is a metasurface that has slits on each cell in order to achieve more radiation characteristics and polarization purity. A tapered balun is used to feed the antenna. The obtained results and radiation diagrams show that this design has been able to have an axial ratio of less than 3 dB in the frequency range of 1.57 GHz to 1.61 GHz. Also, in this frequency range, the maximum gain values (which occurs at θ=0) are different by at least 20 dB compared to the gain around θ=90 . Also, in the mentioned frequency range, S11 values are less than -10 dB and VSWR values are less than 2.

Keywords

wire antenna

loop antenna

tapered balun

circular polarization

GPS antenna