calculate expected attenuation of Signal with known dielectric params of Mediums

Hi There,

Is it possible to deduce expected % attenuation of a signal being transmitted through medium of known dielectric parameters, s11, e'. There would be assumptions that the wave and material is within the beam width and the far field range of the antenna. For example the wave would be traveling through air for 10 feet, some dielectric material < 1 inch, air 10 more feet. The exact dimensions would be known.

I would also be interested if and what software simulation may handle this without paying the Ansoft ticket. A recommended matlab algorithm would be nice. What other sim software might be recommended?

Recommended reading on the topic would be appreciated, especially if I am talking pie in the sky.

TIA