Anritsu S820E - Swr; Group Delay; Smith Chart

S820E UG PN: 10580-00343 Rev. H 6-7
VNA Mode 6-3 Calculating and Displaying S-Parameters
SWR
Applications
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
.
Group Delay
Group Delay (sec) = rate of change of phase over a specified frequency
aperture
Applications
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.
Smith Chart
Smith Chart = graphical tool for plotting impedance or admittance data
versus frequency
Applications
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.
SWR
1 S
xx
+()
1 S
xx
–()
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=