Concepts and Features
R&S
®
ZNB/ZNBT
128
User Manual 1173.9163.02 ─ 53
Combining different detectors
The detector setting in the More Ratios menu applies to both the numerator and the
denominator wave quantity. To allow for different detector settings, measure the numer-
ator and denominator wave quantities individually and use trace functions to calculate
the ratio. A possible application is the comparison of different detector settings for a
particular trace.
Error Messages
The analyzer generates a warning if the selected measurement time for the "AVG..."
detectors is too long. At the same time, bit no. 15 in the
...INTegrity:HARDware
status register is set. Reduce the measurement time and/or reduce the IF bandwidth
until the warning disappears. A warning also appears if the measurement time for the
"AVG..." detectors is too short. Increase the measurement time and/or increase the IF
bandwidth until the warning disappears.
5.3.6
Unbalance-Balance Conversion
Unbalance-balance conversion is the simulation of one or more unbalance-balance
transformers (baluns) integrated in the measurement circuit. It converts the DUT ports
from an unbalanced state into a balanced state and virtually separates the differential
and common mode signals. The analyzer measures the unbalanced state but converts
the results and calculates mixed mode parameters, e.g. mixed mode S-parameters. No
physical transformer is needed.
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. For a two-port analyzer, a single balanced port can be defined.
VNA
1
2
Physical VNA ports
Common
mode
Differential
mode
Physical
transformer
(balun)
DUT
VNA
1
2
DUT
Balanced port
Internal balance-
unbalance
conversion
Logical
VNA 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.
Measurement Results
