"John S" wrote in message ...

On 8/17/2015 4:04 PM, Wayne wrote:
I thought I'd look up this subject and got nowhere. I didn't find it in
Kraus and some internet searching was futile.

As an example, if we have a transmitting dish that precisely covers a
receiving dish (and vice versa), such that there is no path loss. What
happens at the receiving dish with respect to re-radiated power?

That power is apparently sent back to the transmitter and then?

Antennas For All Applications by John D. Krause and Ronald J. Marhefka, 3rd
edition, ISBN 0-07-053243-5.

Page 29, immediately below equation 10:
"When the antenna is receiving with a load resistance Rl matched to the
antenna radiation resistance Rr(Rl=Rr), as much power is reradiated from
the antenna as is delivered to the load. This is the condition of /maximum
power transfer/ (antenna assumed lossless)."

They go on to say it applies to 1/2 wavelength dipoles but does not apply
to all antennas.

But, as in some other references I checked, the re-radiation is declared
rather than explained.

Way back in another life when I worked in the "black" world, we did some
mischief using reradiation.

Also, years ago in bug detection we hit locations with rf and looked for 3rd
harmonics generated by diode type junctions.
It worked pretty well, but we found a lot of bogeys, such as corroded wiring
connections.