what happens to reflected energy ?
Keith Dysart wrote:
. . .
So there you have it. The interpretation that the forward
and reflected wave are real and transport energy leads to
the conclusion that on a line charged to a constant DC
voltage, energy is flowing in the forward direction and
energy is flowing in the reflected direction.
Because it is obvious that there is no energy flowing on
the line, this interpretation makes me quite uncomfortable.
Now there are several ways out of this dilemma.
Some say they are only interested in RF (and optics), and
that nothing can be learned from DC, steps, pulses or other
functions. They simply ignore the data and continue with
their beliefs.
Some claim that DC is special, but looking at the equations,
there is no reason to expect the analysis to collapse with
DC.
The best choice is to give up on the interpretation that the
forward and reflected voltage waves necessarily transport
energy. Consider them to be a figment of the analysis technique;
very convenient, but not necessarily representing anything real.
As an added bonus, giving up on this interpretation will remove
the need to search for “where the reflected power goes” and
free the mind for investment in activities that might yield
meaningful results.
...Keith
Well done, Keith. Thanks.
Roy Lewallen, W7EL
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