Miniaturization of dual‐polarized crossed dipole antenna using dielectric loading

Abstract

In this article, dielectric loading is introduced as a method for miniaturizing dual‐polarized crossed dipole antenna. Specifically, the size, thickness, and relative permittivity of dielectric slab are considered as three critical parameters for antenna miniaturization. It is found that the three parameters have different loading effects on a crossed dipole, due to distinct modal current and field distributions. Furthermore, an antenna configuration loaded by 3‐layer dielectric slabs is proposed. Utilizing the slow‐wave property of dielectric loading, two miniaturized crossed dipole antennas with size of 40 mm × 40 mm (0.29 λ0 × 0.29 λ0) are devised, exhibiting an at least 21% size reduction over the previous dual‐linearly‐polarized crossed dipole antennas. Simulated and measured results demonstrate that the proposed antennas have wide bandwidth (1.71‐2.69 GHz), desirable impedance matching (VSWR <1.5), stable radiation pattern, and low gain loss.