Concepts and Features
R&S
®
ZNA
114
User Manual 1178.6462.02 ─ 12
●
The measurement is not impaired by the non-ideal characteristics of the balun (e.g.
error tolerances, limited frequency range).
●
Calibration can be performed at the DUT's ports. If necessary (e.g. to compensate
for the effect of a test fixture), it is possible to shift the calibration plane using length
offset parameters.
●
Differential and common mode parameters can be evaluated with a single test
setup.
5.3.6.1
Balanced Port Configurations
Defining a balanced logical port requires two physical ports.
The physical VNA ports are equivalent and can be freely combined to balanced (logi-
cal) ports. Moreover, it is possible to assign arbitrary, independent reference impe-
dance values to each unbalanced port and to the differential and common mode of
each logical port.
Example:
2 physical ports
: Reflection measurements on 1 balanced port
Bal.
port
Differential mode
Z
ref
= Z
0d
Common mode
Z
ref
= Z
0c
DUT
Balanced port:
Log.
VNA
port
3 physical ports
: Reflection and transmission measurements on 1 balanced port
Bal.
port
Differential mode
Z
ref
= Z
0d
Common mode
Z
ref
= Z
0c
DUT
Balanced port:
Log.
VNA
port
Single
ended
port
Single-ended
(unbalanced) port
Z
ref
= Z
connector
4 physical ports
: Reflection and transmission measurements on 1 or 2 balanced ports
Bal.
port
Differential mode
Z
ref
= Z
0d
Common mode
Z
ref
= Z
0c
DUT
Balanced port:
Log.
VNA
port
Single
ended
ports
Single-ended
(unbalanced) ports
Z
ref1
= Z
connector1
Z
ref2
= Z
connector2
Bal.
port
Differential mode
Z
ref
= Z
0d
Common mode
Z
ref
= Z
0c
DUT
Balanced port:
Log.
VNA
port
Bal.
port
Differential mode
Z
ref
= Z
0d
Common mode
Z
ref
= Z
0c
Balanced port:
Log.
VNA
port
A balanced port configuration is defined in two steps: First, select the pairs of physical
ports that you want to combine to form balanced ports. Second, define the two refer-
Measurement Results
