Thanks for help, I think I wrongly explained my problem, here is the
question:
1/ I design an antenna, for instance a 3 el 20m beam.
2/ I enter into EZNEC wires dimensions, spacing, height, source.....
3/ EZNEC calculates gain, F/B, SWR....and results are acceptable.
4/ Now let's suppose my objectives are max F/B as I have a QRM source
opposed to my favourite transmitting direction and SWR 1.5 on a given
frequency range as my transceiver is very SWR sensitive and I can't use an
antenna tuner.
I accept changing wire lengths and spacing but not boom length.
Is there a way to have EZNEC, or another software, doing automatic
iterations until it reaches the best F/B-SWR compromise ?

JC - F8ND


"Reg Edwards" a écrit dans le message de
news: ...

"JC" wrote in message
...
Is there a software which can design an antenna (like EZNEC or
similar )
then allows to automatically optimize its dimensions according to
given
requirements: max gain, F/B, min swr... and accepted dimensional
parameters
changes: boom length, spacing....
JC
----------------------------------------------------------------------
-------
Dear JC,

You don't need software. What you describe is non-existent anyway.
What you want is a long experienced antenna designer who can be
permanently engaged on your behalf. There are very few of such
creatures about.

You will have to be numerically quite specific about particular
problems. And even then you will get solutions which, with luck, are
probably only in the right ball-park.

On the other hand, ball-park solutions are perfectly satisfactory. In
the nature of events, no-one has ever solved an antenna problem which
is other than in a ball-park. Fortunately, antennas work quite well
even when in the wrong ball-park.

Download a free copy of EZNEC and in a few months time you may have
solved your first complicated, specific problem. As time goes on, you
will become more adept and there will be no need to engage a long
experienced antenna designer. You will have become one youself and
can offer your services for hire.

If you have a specific problem you may, if you are lucky, find a
computer program written by someone who has already solved it. But its
highly unlikely to be exactly the same problem. It will be in a
somewhat different ball-park.

Optimisation is out! You will have to contend with whatever you can
get your hands on. What's been done before. Take it or leave it!
----
Reg.