Fundamental characteristics of a strip folded dipole antenna with a feed line having a hemispherical structure

The purpose of this study is to analyze the broadband characteristics of a SFDA with a feed line having a hemisphere structure in a free space or on the dielectric substrate. We can expect that the impedance matching and broadband characteristics will be obtained by a feed line having a curved structure in a free space and on the hemispherical dielectric substrate. And the resonant frequency of the antenna can be lowered by using the hemispherical structure as the substrate, which leads to the miniaturization of the antenna. First, the parametric study on the feed line with respect to the length and spacing between two parallel lines is performed in a free space and on the hemispherical dielectric substrate by using the electromagnetic simulator (CST Microwave Studio). Next, a prototype is fabricated and measured in order to verify the simulated results.