HP 8712C - How the Reflection Measurement Works

I
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I
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Making Measurements
Measuring Impedance Magnitude
How the Reflection Measurement Works
A reflection trace can be converted to equivalent parallel impedance using
the model and equations shown in Figure 3-26. In the formula shown in
Figure 3-26, r is the complex reflection coefficient. The complex impedance,
Znes, is computed based on I’ and ZO. The analyzer displays the magnitude of
Znes. This measurement assumes a two-terminal device, connected across the
analyzer’s REFLECTION port.
Reflection (r)
I fr
ZRef, = zo . -
i-r
Figure 3-26. Impedance Calculation for Reflection Measurements
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