Walt, W2DU wrote:
"A semantic problem with the term "Power Flow" also fuels the erroneous
belief that reflected power is fictitious."
Another world-class expert has agreed that power flows.
Energy may or may not flow. It is the accumulation of flows that you pay
for on your monthly electric bill. Power is the rate of delivering
energy (doing wotk), so it can`t stand still. No power flow, no work.
Take it from W2DU. Reflections are important. Reflections occur at
discontinuities.
To the extent that voltage and current are in-phase, they mean real
power. Zo is resistive in a practical r-f transmission line. Incident
and reflected waves both propagate on the line with their individual
voltages and currents locked in-phase. The sum of incident and reflected
waves can`t be relied upon to indicate power, but infividually each wave
can indicate true power.
The reflected wave interferes with the incident wave to produce standing
waves. These represent the impedance distribution along the line. They
do not represent variation of power in the wave in eather direction.
Best regards, Richard Harrison, KB5WZI
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