Single-Polarized Wideband Planar Tightly Coupled Array with Low Profile Using FSS Superstrate

Abstract

A single polarized planar tightly coupled dipole array over 6–18 GHz is presented in this paper. The array has an unbalanced feed scheme and a novel frequency selective surface (FSS) superstrate, which contribute to obtain a low profile with volume size of 0.48λ h×0.48λh×0.31λh (λh is the free-space wavelength at the highest frequency) and wide scanning angle performance. The characteristics of infinite array are provided. The proposed antenna array achieves contiguous bandwidth over 6–18 GHz when scanning down for 40° at H-plane and 50° at E-plane using a VSWR < 3 metric. Besides, the radiation efficiency is demonstrated to be above 80% for the proposed antenna unit.