Design of Broadband Quasi-Yagi Antenna Using a Folded Dipole Driver

Ta, Son Xuat; Kim, Byoung-Chul; Choo, Ho-Sung; Park, Ik-Mo

doi:2011.11.3.227

J. Electromagn. Eng. Sci > Volume 11(3); 2011 > Article

Journal of the Korean Institute of Electromagnetic and Science 2011;11(3):227-234.
DOI: https://doi.org/10.5515/JKIEES.2011.11.3.227

Design of Broadband Quasi-Yagi Antenna Using a Folded Dipole Driver

Son Xuat Ta¹, Byoung-Chul Kim¹, Ho-Sung Choo², Ik-Mo Park¹

¹School of Electrical and Computer Engineering, Ajou University
²School of Electronic and Electrical Engineering, Hongik University

Abstract

This paper describes the development of a broadband quasi-Yagi antenna using a folded dipole driver. The antenna is designed on a low-permittivity substrate to reduce the surface wave effect, and hence the gain can be enhanced easily by adding directors. The folded dipole driver is connected to a 50-${Omega}$ microstripline via a simple broadband microstrip-to-coplanar stripline transition with a quarter radial stub. The key motivation for the use of a folded dipole is to increase the input impedance at the driver, allowing a smaller mismatch loss between the antenna driver and the coplanar stripline feed. The proposed antenna has a measured bandwidth of 4.67~6.26 GHz for the -10 dB reflection coefficient, and a flat gain of 4.86~5.15 dB within the bandwidth.

Key words: Broadband, Quasi-Yagi Antenna, Folded-Dipole.