Concepts and features
R&S
®
ZND
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User Manual 1173.9557.02 ─ 61
possible through connections are measured by default. If you want to apply the
"Reduced Through" logic also for each port assignment, you can activate it in the
system configuration.
4.5.1.12
Complementary isolation measurement
For each port pair in a manual transmission normalization or TOSM calibration, the
Through measurement can be complemented by an isolation measurement. This mea-
surement accounts for possible crosstalk between the related test ports (e.g. on a test
fixture).
If isolation is measured, the corrected transmission coefficient of the DUT is calculated
as:
(Transmission coefficient DUT – Isolation) / (Transmission coefficient Through – Isola-
tion)
There is no dedicated physical standard for isolation measurement; it is recommended
to terminate the test ports suitably (e.g. with 50 Ω loads).
4.5.2
Calibration standards and calibration kits
A calibration kit is a set of physical calibration standards for a particular connector type.
The magnitude and phase response of the calibration standards (i.e. their S-parame-
ters) must be known or predictable within a given frequency range.
The standards are grouped into several types (Open, Through, Match,...) correspond-
ing to the different input quantities for the analyzer's error models. The standard type
also determines the equivalent circuit model used to describe its properties. The circuit
model depends on several parameters that are stored in the cal kit file associated with
the calibration kit.
As an alternative to using circuit models, it is possible to describe the standards with S-
parameter tables stored in a file.
The analyzer provides many predefined cal kits but can also import cal kit files and cre-
ate kits:
●
A selection of predefined kits is available for all connector types. The parameters of
these kits are displayed in the "View / Modify Cal Kit Standards" dialog, however, it
is not possible to change or delete the kits.
●
Imported and user-defined kits can be changed in the "Calibration Kits" dialog and
its various subdialogs.
Calibration kits and connector types are global resources; the parameters are stored
independently and are available irrespective of the current recall set.
Calibration
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