2.10 Extra bits
103
Figure 2.10-2 Incident, reflected, total voltages and standing wave along a mismatched line at t=0.25T s
Figure 2.10-3 Incident, reflected, total voltages and standing wave along a mismatched line at t=0.5 T s
Another
way to see this is through the theory of relative motion. If we were observing the
speed at which point
β moves away from us while standing at point α, we would perceive the speed
of
β as twice the speed of light. That is because our frame of reference, which is anchored on the
incident voltage is moving at speed and point
β is also moving at the same speed but in opposite
direction. So relative to one another, incident and reflected voltages are moving at twice the speed
of light and hence we expect the change in their resultant sum to also change twice as fast as each
wave is propagating. This of course does not mean to say that there is anything physically changing
at twice the speed of light but that there are two quantities which are simultaneously changing at
such a speed.
α
β
α
β
t=0.25T
t=0.5T
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103 www.cadence.com/go/awr
