System Overview
R&S
®
ZVA
84
Getting Started 1145.1090.62 ─ 13
With option R&S ZVA-K6, True Differential Mode, the analyzer can generate balanced
waves at arbitrary reference planes in the test setup and determine balanced results
such as S-parameters, wave quantities and ratios. The true differential mode also pro-
vides two additional sweep types, the "amplitude imbalance" and "phase imbalance"
sweeps. What is said below is valid for both the simulated balanced mode and the true
differential mode.
To perform balanced measurements, a pair of physical analyzer ports is combined to
form a logical port. The balanced port of the DUT is directly connected to the analyzer
ports
Unbalance-balance conversion avoids the disadvantages of real transformers:
●
There is no need to fabricate test fixtures with integrated baluns for each type of
DUT.
●
The measurement is not impaired by the non-ideal characteristics of the balun (e.g.
error tolerances, limited frequency range).
●
Calibration can be performed at the DUT's ports. If necessary (e.g. to compensate
for the effect of a test fixture), it is possible to shift the calibration plane using
length offset parameters.
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Differential and common mode parameters can be evaluated with a single test
setup.
3.3.2.12
Balanced Port Configurations
Defining a logical ports requires two physical analyzer ports. The ports of an analyzer
are equivalent and can be freely combined. Moreover, it is possible to assign arbitrary,
independent reference impedance values to each unbalanced port and to the differen-
tial and common mode of each logical port. The following types of balanced devices
can be measured with 2-port, 3-port and 4-port analyzers:
2-port analyzers: Reflection measurements on 1 balanced port
Measured Quantities
