Concepts and Features
R&S
®
ZNB/ZNBT
146
User Manual 1173.9163.02 ─ 53
arator" in the "Export ... Data" dialogs. A semicolon is inserted before the end of each
line.
The stimulus values are arranged in ascending order.
5.4.2.3
Finding the Best File Format
The file format depends on how you want to use the exported data.
Use a
Touchstone
file format to export single-ended S-parameter data traces to a file
that can be evaluated with applications such as Agilent's Microwave Design System
(MDS) and Advanced Design System (ADS), and to convert mixed mode parameters
back to single-ended parameters. The data must be acquired in a frequency sweep.
Note the
"Conditions for Touchstone file export"
Use the
ASCII (*.csv)
format if you want to do one of the following:
●
Import the created file into a spreadsheet application such as Microsoft Excel.
●
Export an arbitrary number of traces, multiple traces with the same parameter or
memory traces.
●
Export traces acquired in a power sweep or CW sweep.
●
Use export options.
Use the
Matlab (
*.dat
)
format if you want to import and process the trace data in
Matlab.
5.4.3
Memory-Mapped Trace Data Transfer
The VNA firmware uses the
Named Shared Memory
Windows feature to share trace
data with other processes running on the instrument. Such processes or applications
can read trace data directly from the shared memory, which is much faster than using
SCPI commands.
Multiple traces can be written to the same shared memory buffer. For each of these
traces, the firmware stores a configurable number of formatted or unformatted trace
values to a contiguous part of the shared memory.
●
A formatted (real) trace value takes up 8 bytes of memory.
●
An unformatted (complex) trace value takes up 16 bytes: 8 bytes for the real part, 8
bytes for the imaginary part.
Memory-mapped trace data transfer is a pure remote control feature. Once set up, the
VNA firmware refreshes the shared memory trace data with every sweep. Other pro-
cesses can read these data via standard APIs for Windows
Named Shared Memory
that are available for various programming languages.
You can create multiple shared memory buffers, e.g. with different intended life span.
Operations on Traces
