An improved FDTD model for the feeding gap of a thin-wire antenna

Author

Watanabe, So-ichi ; Taki, Masao

Author_Institution

Commun. Res. Lab., Minist. of Posts & Telecommun., Tokyo, Japan

Volume

8

Issue

4

fYear

1998

fDate

4/1/1998 12:00:00 AM

Firstpage

152

Lastpage

154

Abstract

In calculations using the finite-difference time-domain (FDTD) method, the feeding gap of a thin-wire antenna is often modeled by a so-called “one-cell gap” which lets the feeding gap to be one interval of Yee´s lattice. This is often inconsistent with the actual situation and it causes error in FDTD calculation results. This work shows that the error due to the one-cell gap model is strongly dependent on the cell size, and we present an improved FDTD model which assumes an infinitesimally narrow feeding gap. We show that the antenna input impedance calculated with the new gap model is barely affected by the cell size and agrees well with the method of moments (MoM) calculation results for an infinitesimal gap. Furthermore, we clarify the dependence of error of a one-cell gap on the cell size on the basis of the proposed model

Keywords

antenna theory; dipole antennas; electric impedance; error analysis; finite difference time-domain analysis; wire antennas; FDTD model; antenna input impedance; cell size dependency; feeding gap; finite-difference time-domain method; one-cell gap model error; thin-wire antenna; Antenna feeds; Dielectric losses; Dipole antennas; Electromagnetic analysis; Finite difference methods; Humans; Impedance; Lattices; Moment methods; Time domain analysis;

fLanguage

English

Journal_Title

Microwave and Guided Wave Letters, IEEE

Publisher

ieee

ISSN

1051-8207

Type

jour

DOI

10.1109/75.663515

Filename

663515