> The concept of reflection energy on transmission lines is QUITE
> solid. To deny that is to deny Maxwell's Equations! By the
> principle of superposition, the current, voltage, and power at any
> point on a transmission line are the sum of the forward and
> reflected current, voltage, and power at that point.
Agreed, Jim. But I would take exception to "power at any point on a
transmission line."
Part of the problem as I see it stems from viewing reflected power as a
"thing" that reflects. Reflected power is an end result of line voltage,
current and reflection coefficient. Power in and of itself does not
reflect. Power is an amount of energy dissipated over time.
By contrast, a wave reflects and is made up of a combination of voltage and
current. The degree of power ultimately lost is contingent on the
reflection cefficient (i,e., the amplitude of the reflection), line loss,
and Z seen by the reflection when traveling back to the source.
So, when we use the term "reflected power," we really need to discuss it in
these other terms or we end up talking in circles.
Paul, W9AC
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