2.8 Reflection and Transmission in unterminated, shorted, matched and mismatched line
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2.8 Reflection and Transmission in unterminated, shorted, matched and
mismatched lines
We will now look at what happens when we terminate an actual transmission line, with
characteristic impedance Z
0
=50Ω, in different impedances. The circuit which we will be analysing is
shown in Figure 2.8-1 and we will be using sinusoidal stimuli from now on.
Figure 2.8-1 Transmission line of characteristic impedance Z
0
terminated with impedance Z
L
Figure 2.8-2 (a) and Figure 2.8-2 (b) show incident, reflected, and transmitted voltages for an open-
circuit and a short-circuit termination respectively.
Figure 2.8-2 Incident, Reflected and Transmitted voltage for a line terminated with (a) an open circuit (b) a short circuit
As is to be expected, if there is a short or open circuit at the end of the line, the entire signal is
reflected.
Z
L
V
S
Z
0
Transmission Line
──── Incident
──── Reflected
──── Incident
──── Reflected
(a)
(b)
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