Voltage standing wave ratio in other cases - opracowanie

Voltage standing wave ratio We recall from Chapter 2 the results
S =
Rmax
Z0
= rmax (3.7)
S =
Z0
Rmin
=
1
rmin
(3.8)
and the fact that the point of maximum voltage on the line occurs as the point of
maximum impedance and the point of minimum voltage on the line occurs at the point of
minimum impedance, and that those points are distant a quarter of a wave length apart.
These matters are illustrated in Figure 3.7 which shows the locus of a voltage reflection
factor, which originates from a point at which the normalised load impedance is zL, as
we move back along the line away from the load.
When that locus intersects the horizontal axis to the right of the origin, the voltage
reflection factor has become real and positive, and maximum voltage and impedance
occur at that point. Moving further along the line away from the load produces a second
intersection of the horizontal axis, this one to the left of the origin, at which point the
voltage reflection factor has become real and negative, and the point of minimum voltage
and impedance is encountered. We see that the movement from the point zL towards the
input end of the line passes through points of voltage maximum and minimum on the
line, as shown in Figure 3.7.
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