VNA concepts and features
R&S
®
ZNL/ZNLE
243
User Manual 1178.5966.02 ─ 19
The following general rules apply:
●
Individual entries in a network data line are separated by whitespace
●
In version 1.1 files, no more than four parameters are allowed per network data
line. No restriction exists on the number of data pairs on a line in version 2.0 files.
●
The network data blocks are arranged in ascending order of frequency
For segmented sweeps, the R&S
ZNL/ZNLE makes an exception to the strict "ascend-
ing order" principle. During export, the segments are always kept together, which can
result in downward "frequency jumps" at segment borders.
Data arrangement
During export, for each block, the R&S
ZNL/ZNLE arranges the frequency value f and
network parameter data (
Nij
)
1≤i,j≤n
as described in the Touchstone 1.1 standard.
●
n = 1
f N11
●
n = 2
f N11 N21 N12 N22
The data blocks are arranged in ascending order of frequency.
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
ZNL/ZNLE 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.
Operations on traces