NEC-LIST: How to get actual far field value??

I have an interest in evaluating the performance of electrically small
antennas. So far, I have been using NEC4WIN to do this. I suspect the
same situation would occur with any other version of NEC, although
maybe I need to download something else. Anyway, my problem is this:

When I set up a small antenna, like a short vertical, and look at the
fields, I end up with far field values of something like 2 to 5 dBi.
If I go to a full size vertical, I get something similar. Of course,
the impedance and swr for the full size antanna are much better, but
the implication is that the mismatch and the small antenna size do not
affect the far field field strength. Of course, this is not true.
Just the mismatch, alone, would greatly decrease the radiated power,
and the length of the radiating element would also greatly decrease
the field strength. What I want to know is if there is a version of
NEC (or something else) available that would allow me to actually
predict the field strength of an electrically small antenna. For
example, if I use a 60" whip at 30 MHz, I would suspect that the field
strength would be at least 10 or 20 dB lower than if I fed a quarter
wave vertical with a 50 ohm source, but I don't get that with NEC.

Any help would be appreciated.

Ed
Received on Thu Sep 25 1997 - 10:38:03 EDT