Agilent Technologies ENA Series User Manual page 522

Measurement Examples
Measuring an Unbalanced and Balanced Bandpass Filter
Step 1. Set the port reference impedance of port 1 on the DUT (unbalanced) to 50 Ω.
Setting Description
Reference impedance of test port 1: 50 Ω
Step 2. In order to set the impedance of the differential mode of port 2 on the DUT (balanced) to
200 Ω, set the impedances of two unbalanced ports before conversion each to 100 Ω.
Setting Description
Reference impedance of test port 2: 100 Ω
Reference impedance of test port 3: 100 Ω
NOTE
Always set the reference impedances of the two test ports before balanced conversion to
the same value.
Step 3. Turn on the port reference impedance conversion function.
Setting Description
Port reference impedance conversion: ON
The reference impedance of the command mode of port 2 on the DUT is set to 50 Ω. The
impedance of the differential mode of that port may be set and modified independently of
setting the two-port reference impedances before balanced conversion. For more
information, see "Converting Reference Impedance of Balanced Port" on page 300.
Figure 15-30 shows the results of port reference impedance conversion.
Figure 15-30 Results of port reference impedance conversion
516
Key Operation
-
Fixture Simulator
-
Port Z conversion Port 1 Z0
Key Operation
-
Port 2 Z0
-
Port 3 Z0
Key Operation
(turns it
Port Z Conversion ON
-
-
)
Chapter 15