Rohde & Schwarz SMBV100B, Руководство пользователя

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Configuring the Internal Baseband Source
R&S
®
SMBV100B
146 User Manual 1178.4460.02 ─ 03
For a description of the multi-carrier, multi-segment and multi-carrier continuous wave
functions, refer to:
●
Chapter 3.8, "Generating Multi-Carrier Signals" , on page 223
●
Chapter 3.7, "Generating Multi-Segment Waveform Files" , on page 193
●
Chapter 3.9, "Generating Multi-Carrier Continuous Wave Signal" , on page 241
3.6.2.1 Waveform Files Sources
In ARB mode, the R&S SMBV100B uses ARB waveform files to obtain the digital I/Q
data of the baseband signal. The R&S SMBV100B can replay any waveform file stored
on a network drive but it can also generate and replay simple waveforms for test pur-
poses.
What is a waveform?
A waveform is a file with specified file format containing raw IQ samples. The IQ values
are calculated in advance and stored as waveform files with a predefined extension
*.wv
.
When waveforms are created by the R&S SMBV100B, the instrument inserts a wave-
form header at the beginning of each created ARB file. The header of the generated
I/Q data files consists of "tags" which are enclosed in braces { }.
For detailed description on all available tags and for information on how to query them
or to create waveforms manually, refer to
Chapter 3.6.5, "Tags for Waveforms, Data
and Control Lists" , on page 177.
Waveform file sources
Depending on whether the R&S SMBV100B creates the waveform files itself or not,
two waveform files sources can be distinguished:
●
Internally generated waveforms
The ARB generator enables the calculation and the generation of multi-segment
and multi-carrier waveform files. The ARB generator provides also a built-in func-
tion to create a test waveform (e.g. a sine or rectangle signal) and keep it as a file
or in the RAM.
Several digital standards provide the special function "Generate Waveform File".
With this function, the calculated signals are stored as a waveform file that can be
afterwards played by the ARB generator.
●
Externally generated or created waveforms
The ARB can also process externally created waveform files, for example:
–
The waveform files generate d by the software R&S WinIQSIM2, the
R&S ARB Toolbox, the R&S Pulse Sequencer
– Signals calculated using a mathematical program such as MATLAB.
See Chapter 3.6.5, "Tags for Waveforms, Data and Control Lists" ,
on page 177.
Irrespectively of the way they are created, you can load the externally generated
waveform files into the instrument via one of the available interfaces (USB, LAN or
Using the Arbitrary Waveform Generator (ARB)