Cecil Moore wrote:

Jim Kelley wrote:

Good point, Richard. Wf = Wl + Wr. Amidst all this consternation
about conserving the energy in canceled waves, we should not lose
sight of the fact that it is *reflections* (not canceled waves) which
cause forward power to measure greater than power dissipated in the load.


Now all you have to do is figure out how those reflected
waves reverse their momentum to become forward waves.
You have never offered any explanation for that phenomenon
while criticizing everyone else's explanations.

I don't criticize everyone else's explanations, Cecil. We've
discussed this countless times. It's not new or revolutionary, and
there are of course pictures of it in physics books that you can look
at. Born and Wolf has one, and so does Roller Blum, Physics Volume 2
- as I've pointed out before. You even have a similar chart
illustrating it on your web page. Obviously I didn't invent it. It's
been right there all along, just as I've told you countless times
before, and naturally it (of necessity) blends seamlessly with all of
your other favorite quotations.

In considering the transmission line matching transformer scenario (or
the antireflection coating), when we sum up all of the partial
reflections at each interface during the transient period, the sum
ultimately reaches and establishes the steady state conditions. The
sum of the reflections at each iteration show exactly how energy makes
its way from source to load.

But to follow the energy path correctly we absolutely have to approach
the problem either from the standpoint of fields or as voltages.
Power doesn't propagate. Fields do - therefore only an analysis from
that standpoint avoids pitfalls and misconceptions. If you want to
see how energy moves, then power should be calculated after a proper
voltage analysis, not in lieu of one. When approached in this manner,
it is very simple to see how energy actually does move through the
system. Note that you get the same answer in the end either way.
Both approaches obviously conserve energy. Scattering parameters and
irradiance equations are accurate shortcuts to that end. But one
should be careful not to read (or invent) too much physical science
into the shortcuts. They're mathematical shortcuts, not
phenomenological descriptions of nature.

ac6xg