Rohde & Schwarz ZVL series, Operating Manual

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R&S
®
ZVL System Overview
Calibration Overview
Quick Start Guide 1303.6538.62-01 95
Calibration Type Standards Parameters Error Terms General
Accuracy Application
TOSM Open, Short,
Match
1)
(at each
port),
Through
2)
(between the 2
ports)
All Reflection
tracking,
Source match,
Directivity,
Load match,
Transmission
tracking
High Reflection and transmission
measurements on DUTs with 2
ports.
1) Or any other 3 known one-port standards. To be used in a guided calibration, the
known standards must be declared to be open, short, and match irrespective of their
properties.
2) Or any other known two-port standard. See remark above.
E
The calibration type must be selected in accordance with the test setup. Select the
calibration type for which you can obtain or design the most accurate standards
and for which you can measure the required parameters with best accuracy.
3.3.2.1 Normalization
A normalization is the simplest calibration type since it requires the measurement of
only one standard for each calibrated S-parameter:
E
One-port (reflection) S-parameters (S
11
, S
22,
...) are calibrated with an open or a
short standard providing the
reflection tracking
error term.
E
Two-port (transmission) S-parameters (S
12
, S
21,
...) are calibrated with a through
standard providing the
transmission tracking
error term.
Normalization means that the measured S-parameter at each sweep point is divided by
the corresponding S-parameter of the standard. A normalization eliminates the
frequency-dependent attenuation and phase shift in the measurement path (reflection
or transmission tracking error). It does not compensate for directivity or mismatch
errors. This limits the accuracy of a normalization.
3.3.2.2 Full One-Port Calibration
A full one-port calibration requires a short, an open and a match standard to be
connected to a single test port. The three standard measurements are used to derive
all three reflection error terms:
E
The short and open standards are used to derive the
source match
and the
reflection tracking
error terms.
E
The match standard is used to derive the
directivity
error.
A full one-port calibration is more accurate than a normalization but is only applicable
for reflection measurements.