VNA concepts and features
R&S
®
ZNL/ZNLE
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User Manual 1178.5966.02 ─ 19
b)
SYSTem:DATA:MEMory:ADD '<TrName2>', FDATA|SDATa, #Values2
Use
to query the offset in bytes of the sec-
ond trace data block. Processes that want to read the trace data from the buffer
need to know this offset. Its size depends on whether the first trace data block
contains formatted (real) or unformatted (complex) values.
c) ...
Use
SYSTem:DATA:MEMory:OFFSet?
to query the offset of the last added trace.
3. Create the named shared memory buffer:
'<ShMemName>'
The name must be unique. Before the
COMMit
you can use
to query the names of existing shared memory buffers.
The size of the last created shared memory buffer can be queried using
Use a shared memory buffer
After you have created a named shared memory buffer, you can access it – from the
instrument – using your favorite programming language and API. With Python, for
instance, you can use the
mmap
module for this purpose.
Delete a shared memory buffer
To delete a shared memory buffer and free the occupied memory, you can use one of
the following commands.
1.
'<ShMemName>'
deletes a single shared memory buffer by name.
2.
deletes all shared memory buffers created using
SYSTem:DATA:MEMory:COMMit
.
9.5
Calibration
Calibration or system error correction is the process of eliminating systematic, reprodu-
cible errors from the measurement results (S-parameters and derived quantities). The
process involves the following stages:
1. A set of calibration standards is selected and measured over the required sweep
range.
For many calibration types, the magnitude and phase response of each calibration
standard (i.e. its S-parameters if no system errors occur) must be known within the
entire sweep range. In some calibration procedures (e.g. for
of the characteristics of the standards can be auto-determined due to implicit
redundancy (self-calibration).
Calibration
