Concepts and features
R&S
®
ZNA
267
User Manual 1178.6462.02 ─ 20
Required to calculate the calibrated S-parameters and their uncertainties. If rele-
vant settings are changed on the VNA, these changes are also propagated to the
METAS VNA Tools.
●
Measured S-parameters (uncalibrated)
The raw ("uncalibrated") data are handed over to the METAS VNA Tools after
every sweep for real-time correction and uncertainty analysis.
Only a single VNA channel can be METAS calibrated at a time.
Verification
To get precise information about the absolute measurement uncertainty after calibra-
tion, you can use verification standards, which are DUTs precisely characterized by the
manufacturer. Verification kits, which include multiple standards, deliver the most accu-
rate results for the measurement uncertainty.
Verification kits R&S
ZV-Z4xx from Rohde&Schwarz contain a male and a female off-
set short, a male and a female mismatch, an attenuator and a stepped through. These
verification standards differ substantially from the conventional calibration standards –
Open, Short and Match – because they have different impedances. They are charac-
terized in steps of 250 MHz and specified together with their measurement uncertain-
ties. Characterization and uncertainties are accredited by the DAkks (Germany’s
national accreditation body).
The VNA firmware compares the uncertainties calculated by the METAS VNA Tools
with the accredited uncertainties and presents both uncertainty bands graphically. To
pass verification, the calculated band must be within the accredited band for the spe-
cific standard.
4.7.13
Security write protection
R&S
ZNA-K51
With software option R&S
ZNA-K51 "Security Write Protection" (SWP), the firmware
can be run in write-protected mode, i.e. all data that would otherwise be written to the
C:
drive of your VNA are kept in RAM instead. After a restart of the instrument, these
data are gone without a trace.
RAM usage is limited to 1
GByte. When 90% (900 GByte) is used, a warning is dis-
played requesting you to reboot the instrument. When 100% is reached, the reboot is
performed automatically.
Option R&S
ZNA-K51 is delivered as a separate installer, which has to be run on the
R&S
ZNA and requires administrative privileges. The installed service runs in the back-
ground and can be accessed via the Windows system tray.
Optional extensions and accessories