Ultrawideband Compact Magnetoelectric Dipole Antenna/Array With Dual-Polarization

Abstract

Design of ultrawideband (UWB) dual-polarized antenna with compact size is presented in this communication, which is composed of a triple-layer magnetoelectric (ME) dipole, a pair of cross-placed <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Gamma $ </tex-math></inline-formula> -shaped feeding structure, and a box-shaped reflector. Three layers of the ME dipole cover low (around 1.5 GHz), middle (3.5 GHz), and high (4.5 GHz) bands, respectively, leading to an ultrawide operating band from 1 to 5 GHz. The total size of the design is 75 ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.75\lambda _{0}) \,\, \times75$ </tex-math></inline-formula> ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.75\lambda _{0}) \,\,\times55$ </tex-math></inline-formula> mm ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.55\lambda _{0}$ </tex-math></inline-formula> ). An array that consists of eight such antenna elements is designed, fabricated, and measured. Results show that the voltage standing wave ratio (VSWR) is less than two over the whole operating band for all ports. For the radiation characteristics, boresight gain ranging from 5.3 to 8.8 dBi is achieved for each antenna element, and when it comes to the array, a peak gain of 17.23 dBi occurs at 4 GHz when all the antenna elements are excited with identical amplitude and phase. Beam scanning is also realized in the whole operating band through phase disposing, and the scanning range is up to ±45° from 1 to 2 GHz and ±30° from 2 to 5 GHz.

Topics & Concepts