A full coarse-grid based finite-difference time-domain (FDTD) model is proposed for an efficient analysis of resistively loaded cylindrical antennas driven by coaxial feed lines. In the case of the electrically thin resistive antenna, the thin-wire approximation is applied to the near fields around the antenna. The resistive antenna is equivalently represented by a series connection of piecewisely lumped resistors along the antenna axis. And the coaxial line is replaced by an equivalent source over the feed aperture of the line. Then the corresponding FDTD update equations make it possible to implement the full coarse-grid model without additional grid refinements for the antenna and the feed line. The transient reflected feed voltage and the input impedance of resistive antennas are calculated numerically and compared with those of a full fine-grid.
Bibliographical noteFunding Information:
Manuscript received January 06, 2008; revised June 13, 2008. Current version published March 20, 2009. This work was supported in part by the Korean Department of Commerce, Industry and Energy under Grant 10023090 and in part by the Korea Institute of Science and Technology under Contract 2E20730.
- Coaxial transmission lines
- Cylindrical antennas
- Finite-difference time-domain (FDTD) methods
- Loaded antennas
ASJC Scopus subject areas
- Electrical and Electronic Engineering