Anritsu MS2024B - Page 31

VNA Fundamentals 3-4 Calculating and Displaying S-Parameters
Vector Network Analyzer MG PN: 10580-00289 Rev. K 3-7
Table 3-4. SWR
Application Note
SWR, or Standing Wave Ratio, is a measure of the reflection from the DUT input port or
output port, and it must be used, therefore, with S
11
or S
22
.
Table 3-5. Group Delay
Group Delay (sec) = rate of change of phase over a specified frequency aperture
Application Note
Group Delay is a measure of the time delay of the signals that are propagating through the
DUT versus frequency (using S
21
or S
12
). Group delay is a good measure of phase distortion
through the DUT.
Table 3-6. Smith Chart
Smith Chart = graphical tool for plotting impedance or admittance data versus frequency
Application Note
Use Smith Chart with S
11
or S
22
to plot the input or output impedance of the DUT.
Use the Inverted Smith Chart to plot admittance data.
Note: The Inverted Smith Chart is available only on VNA Master models MS20xxC.
SWR
1 S
xx
+()
1 S
xx
–()
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