R&S ZNB Series User Manual page 154

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R&S ZNB/ZNBT
The first line is fixed, the second reflects the configurable identification string of the
instrument.
Timestamp
The timestamp comment line reflects the time at which the Touchstone file was cre-
ated. For "Version 1.1 (ZNx)" export format, it is represented as Coordinated Universal
Time (UTC):
! Created: UTC 12/24/2020, 5:20:26 PM
The other export formats "Version 1.1" and "Version 2.0" use local time (Greenwich
Mean Time + offset):
! Created: GMT+1 2020-12-24 18:20:26
Renormalization information
If, during export, the S-parameter data were renormalized with port-specific impedan-
ces, these impedances are written to the output file as a comment. In case the port-
specific impedances are different, a note points out that the impedance system under-
lying the data is not interpreted correctly during import:
! The following Port Impedance Renormalization has been used when saving the data.
! PortZ
!
! Note: The Port Impedances differ from the reference impedance of this file.
!
!
For more information, see
For the "Version 2.0" export format, the port impedances are currently not written to the
renormalization information comment. Instead, the real parts of the port impedances
appear as arguments of the [Reference]keyword.
Network data table header
These comment lines indicate the content of the
below it.
As the first column of the data table is always designated to the frequency points, the
first table header comment always starts with ! freq[Hz].
●
"Version 1.1 (ZNx)" export format
For this format, the header explicitly specifies the exported parameters and their
data format. The port numbers of single-ended S-parameters in the header are the
"real" (physical) port numbers:
! freq[Hz] re:S22 im:S22 re:S12 im:S12 re:S21 im:S21 re:
S11 im:S11
Up to port reordering, which is possible via "snp free config" export and via logical
port assignment, the order in which the parameter data occur is the one described
in the Touchstone 1.1 standard. See
User Manual 1173.9163.02 ─ 62
Port1:100+j0 Port2:50+j0
While reading the file the reference impedance value of the option line above
is always used.
"Renormalization of S-parameters"
Concepts and features
on page 159.
Network parameter data
"Network parameter data"
Operations on traces
table right
on page 157.
154