On 9/12/2015 5:33 PM, Brian Morrison wrote:
On Sat, 12 Sep 2015 22:17:27 +0100
"gareth" wrote:

"rickman" wrote in message
...
Uh, if they are matched, there won't be any reflection energy.

Untrue, because you match the inout impedance but not the radiation
resistance,
which in the case of a dipole are largely the same, so, yes, in a dipole it
does all get radiated.



If it doesn't get radiated with a matched antenna that has a small
radiation resistance then that remaining energy is converted into heat
in the antenna/matching network, not reflected back to the Tx.

Picture that with ideal components and then tell me what happens. Or
better yet, since we are talking about antenna geometry and not feed
lines and matching networks, imagine *no* feed line, just a signal
generator with a dipole attached directly to the output. The output
impedance of the generator exactly matches the input impedance of the
antenna in each case. The power measured going into the antenna in each
case is 100 W. Will the emitted field be the same?

--

Rick