Concepts and features
R&S
®
ZNB/ZNBT
249
User Manual 1173.9163.02 ─ 62
●
Channel setup (IF bandwidth, power, ...) and calibration data
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.
Cal kits and verification kits with uncertainties
Cal kits and verification kits with uncertainties have to be provided as
*.zip
or
*.scolv
files. The comprised standards must be provided as
*.sdatb
,
*.sdatcv
,
or
*.calstd
files. The standard filenames must convey information about the file con-
tent:
●
Standard type
–
Cal kit:
open
,
short
,
load
,
match
,
through
,
sliding load
, or
sliding match
–
Verification kit:
offset short
,
mismatch
,
airline
,
mismatch airline
,
att
,
attenuator
, or
stepped thru
●
Gender:
(f)
,
(m)
,
_f_
,
_m_
,
female
,
male
,
(fm)
,
_fm_
, …
If gender information is not found, the standard is assumed sexless.
Optional extensions and accessories