How to model whip antenna with dielectric cylinder

I have been trying to model a monopole antenna with a dielectric cylinder around it using EZNEC 3.0. I have not been successful. Can this be done? Is there another freeware program I could use instead?

Also, I was wondering which kind of polyurethane rubber I should get for the dielectric, the normal kind or the anti static kind that conducts electricity?

I would be grateful for any suggestions on this design.

If the thickness of the dielectric is small compared to a wavelength, you do not need to include it in your analysis. This is especially true of ordinary flexible material which has a low dielectric constant.

I am planning on having the diameter of the cylinder be about 1 eighth of a wavelength and the relative permitivitty about 6. The purpose of the cylinder is to shorten the wavelength and reduce the length of the monopole.

Hi,

go to http://www.feko.co.za and download the evaluation version. (It should run if u just got whip and coating). The program is very much like NEC. Use CO card to coat the whip antenna with you dielectric material.

Hope this helps.

Element7k