7-22
Operating Concepts
S-Parameters
The S-Parameter Menu
The S-parameter menu allows you to define the input ports and test set direction for
S-parameter measurements. The analyzer automatically switches the direction of the
measurement according to the selections you made in this menu. Therefore, the analyzer
can measure all four S-parameters with a single connection. The S-parameter being
measured is labeled at the top left corner of the display.
The S-parameter menu of the ES model analyzer contains the following softkeys:
•
•
•
•
•
• accesses the conversion menu.
• accesses the input ports menu.
The S-parameter menu of the ET model analyzer contains the following softkeys:
•
•
•
• accesses the conversion menu.
• accesses the input ports menu.
Analog In Menu
This menu allows you to monitor voltage and frequency nodes, using the analog bus and
internal counter. For more information, refer to the "Service Menus and Error Messages"
chapter in the service guide.
Conversion Menu
This menu converts the measured reflection or transmission data to the equivalent
complex impedance (Z) or admittance (Y) values. This is not the same as a two-port Y or Z
parameter conversion, as only the measured parameter is used in the equations. Two
simple one-port conversions are available, depending on the measurement configuration.
An S11 or S22 trace measured as reflection can be converted to equivalent parallel
impedance or admittance using the model and equations shown in Figure 7-4.
Refl: FWD S11 (A/R)
Trans: FWD S21 ( B/R)
Trans: REV S12 (A/R)
Refl: REV S22 (B/R)
ANALOG IN Aux Input
CONVERSION [ ]
INPUT PORTS
REFLECTION
ANALOG IN Aux Input
CONVERSION [ ]
INPUT PORTS