SIZE REDUCTION OF SERIES-FED TWO DIPOLE ARRAY ANTENNA USING TOP-LOADED ELEMENTS

摘要

In this article, a method for size reduction of a series-fed two dipole array (STDA) antenna using top-loaded elements is presented. In order to reduce the lateral size of a conventional STDA antenna, rectangular patch-shaped top loading is used for the two dipole elements of the STDA antenna and a grooved ground plane is used by adding a patch at both ends of the ground plane. The effects of varying the length and width of the rectangular patch-shaped top loading on the antenna performances, such as the input reflection coefficient and the realized gain, are investigated. A proposed size-reduced STDA antenna covering a frequency band ranging from 1.7 GHz to 2.7 GHz with a gain>5 dBi is designed and fabricated on an FR4 substrate. The total width of the fabricated prototype of the proposed antenna is reduced by approximately 14.3% compared to the conventional STDA antenna, and it presents a 48.7% bandwidth in the range of 1.68-2.76 GHz and a stable gain of 5.6-6.0 dBi with minimal degradation. Moreover, a front-to-back ratio is improved by about 0.7-4.8 dB.