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Derivation of the Reflection Coefficient?
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September 4th 03, 07:00 AM
Dr. Slick
Posts: n/a
wrote in message ...
Trouble is, (Z2-Z1)/(Z2+Z1) is not always equal to Sqrt(Pref/Pfwd)
What then?
The equality was always iffy when you don't take the absolute value.
But once you do, the equality may hold depending on the equations
you use to derive Pref and Pfwd.
Whether Pref or Pfwd represent something physically meaningful is
another question, also dependent on how you derive them.
...Keith
Cecil,
The ratio Pref/Pfwd is directly related to the ratio [rho].
Pref/Pfwd = [rho]**2 Absolute value brackets are a must!
Consider that after the absolute value brackets, the phase information
is gone. But since we are going to a ratio of average (RMS)
values OR peak values of power, it doesn't matter.
In other words, if you use V**2/R, the "V" can be either peak or
RMS, it doesn't matter, because it is a ratio. And of course, the "R"
doesn't matter either. And of course, the phase information is gone
with
the absolute value brackets.
If you agree that the Pref/Pfwd ratio cannot be greater than 1
for a passive network, then neither can the [Vref/Vfwd]= rho be
greater
than 1 either.
Some people wanna rewrite some books here.
Slick
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