Concepts and features
R&S
®
ZNB/ZNBT
158
User Manual 1173.9163.02 ─ 62
The "snp Free Config" export mode allows you to define
●
the set of (physical) ports whose S-parameters shall be exported and
●
the order in which they are exported
The examples above represent the simple scenario with consecutive ports {1,...,n} and
natural ordering.
Data format
Frequencies are represented as single positive numbers, network parameter data as
pairs of numbers. The
<frequency unit>
and
<data format>
are specified in the
. Numbers can be represented as decimal integers or floating point num-
bers, with "." used as decimal separator. Scientific notation is allowed (e.g.,
1.2345e-12
). No minimum or maximum limits are placed on numerical precision.
For Touchstone export, the R&S
ZNB/ZNBT uses the normalized scientific notation,
with a significand (mantissa) of length 17 (+1 for the minus sign) and an exponent with
maximum length 2 (+1 for the minus sign).
1.00000000009 -2.375070438098596e-01 -4.533104459856211e-01
1.01000000009 -3.132740349817996e-01 -5.874596585157938e-01
1.02000000009 -3.062444919836442e-01 -4.587379501906624e-01
Conditions for Touchstone file export
●
One-port Touchstone files with data from a single trace
Typically, Touchstone files contain a complete set of S-parameter traces of an n-
port network. The only exceptions are
s1p
files created from arbitrary S-parameter
traces using the "s1p Active Trace" export function in the
●
Touchstone files containing S-matrices
–
For a one-port Touchstone file, the reflection coefficient for the specified port
(S
ii
for port i) must be measured. If a full one-port (Refl OSM) or a full n-port
(TOSM, ...) calibration is available for the specified port, it is possible to export
the data even when the trace is not displayed.
–
For a multiport Touchstone file
*.s<n>p
, either a full multiport system error
correction or a complete set of n
2
S-parameter traces must be available.
If the port configuration contains balanced ports, the exported Touchstone file
contains the converted single-ended S-parameters unless you enable "Bal-
anced Params" during export.
–
Export of balanced (symmetric) S-parameters must be enabled. If you want to
export balanced S-parameters, make sure that all these parameters are mea-
sured, and that for each involved balanced port both physical ports are part of
the export.
This type of export can be initiated from the GUI by using the "s<n>p Port ..." or
"snp Free Config. ..." functions of the
Operations on traces
