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Concepts and Features
R&S
®
ZNB/ZNBT
227
User Manual 1173.9163.02 ─ 55
Figure 5-19: S-parameter measurements with uncertainty bands
Required input data for METAS VNA Tools:
●
METAS VNA model (noise floor, trace noise, receiver linearity, drift)
For R&S
ZNB variants that support option R&S
ZNB-K50, the VNA model is provi-
ded by the analyzer firmware.
●
Connector types
Part of the uncertainty calculation is the number of reconnections between calibra-
ted ports and calibration standards or DUT. METAS VNA Tools provides "repeata-
bility models" for various connector types.
●
METAS cable model
As cables (and cable movements) contribute to the measurement uncertainty, the
magnitude and phase stability of the cables must be considered. The VNA firm-
ware uses the cable models available in the local METAS VNA Tools installation.
You can add your cable models using its graphical user interface. Cable models
that ship with the VNA firmware are automatically added to the METAS database.
●
Calibration standard characterizations with uncertainties
Standard cal kit data does not contain information about the uncertainty of the
characterization. However, to get meaningful results, these uncertainties must be
considered and hence a "characterization with uncertainties" must be used.
Rohde&Schwarz calibration kits with accredited calibrations (ACA) include uncer-
tainties.
Optional Extensions and Accessories