Broadband dual‐polarized folded dipole antenna with simple feed structure

Abstract

AbstractA broadband folded dipole antenna for dual‐polarized radiation is presented. It comprises two couples of folded dipoles and a planar reflector. To enhance the impedance matching over broadband, each couple of folded dipoles is parallelly connected by stepped coplanar striplines and then excited by a simple feed structure consisting of a 50‐Ω coaxial cable and a rectangular strip. To stabilize the radiation and further improve the impedance matching during an extremely broadband, a rectangular director is utilized and loaded upon each folded dipole. This antenna provides an extremely broad bandwidth of 77.6% (1.68–3.81 GHz) with return loss >15 dB, and good isolation of larger than 25 dB. It also obtains a steady half‐power beamwidth of 66° ± 4° and a gain of 8.6 ± 0.8 dBi during the broadband. This makes it attractive for mobile communication.