2.8 Reflection and Transmission in unterminated, shorted, matched and mismatched line
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…reaches a maximum again
..and finally comes back to zero. Now we are back to where we started!
It is apparent that, although the location of the maxima and minima of the standing wave do
not change along the direction of propagation (hence the "standing" wave definition), the
instantaneous amplitude of the standing wave does change!
The nulls are spaced at λ/2 hence, if a line is terminated with an open circuit, one could just
measure the distance between two nulls (which is possible with a slotted line) and work out the
wavelength (and hence the frequency) of the wave travelling down the transmission line.
As we will demonstrate in the next section, a short circuit will also do the trick. It is important to
notice that, although the distance between two peaks could also be measured, it would not be as
reliable a measurement, since the standing wave pulsates and hence the peaks are not stable!
α
t=0.7 T
α
β
t= T
Conquer Radio Frequency
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