Wide Beamwidth and Miniaturized Millimeter-Wave Endfire Angled ME Dipole Antenna With Extended Ground
Junhyun Kim, Seung Uk Oh, Tae Hwan Jang
Abstract
In this letter, a wideband, wide beamwidth millimeter-wave endfire magnetoelectric (ME) angled dipole antenna with an extended ground structure is presented. When the ground is expanded and the loop is buried into the ground, there is a miniaturization effect on the antenna size because the effective length of the loop increases, thanks to the additional free space for the current to flow through the ground connected to the loop. Moreover, beamwidth can also be increased because the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E</i> -field can propagate through the ground. The <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E</i> -plane beamwidth of the endfire ME dipole antenna is more than doubled from 50° to 128° at 32 GHz frequency. The core area of the proposed antenna is three times smaller than the existing ME dipole antenna and shows a 24° improvement in coverable range compared with the existing ME dipole array when applying actual beamforming through the implementation of a 1 × 4 antenna. The proposed antenna demonstrates notable features, such as a 128° <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E</i> -plane beamwidth, 140° <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">H</i> -plane beamwidth, 48% fractional bandwidth for <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">S</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> , and a 42.4% 3 dB gain bandwidth.