Rohde & Schwarz SMBV100A, Руководство пользователя

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Instrument Function
R&S
®
SMBV100A
274 Operating Manual 1407.6062.32 ─ 08
5.8.2 Data and Signal Sources in Baseband
This section describes the common characteristics of the signals used for generating the
baseband signal for all standards, including for example all listed data sources. The
selection in the digital menus at any given time depends on the parameter and standard
concerned and is clear from the selection list offered in the dialog. The external data
sources may therefore not be available in certain cases.
Characteristics which are uniquely specific to particular standards are described in the
corresponding manual.
The following input signals are used when digital modulation signals are being generated:
●
Modulation data
●
Clock signals
●
Control signals
The input signals can be both internally generated and supplied from an external source.
The internally generated clock signals are output on the CLOCK connectors.
Likewise control signals and also trigger signals for triggering signal generation in the
R&S Signal Generator can be internally generated or supplied from an external source.
Two marker output signals for synchronizing external instruments can be user-defined.
Externally computed waveform files can be loaded in the instrument using computer
interfaces or IEC bus.
Waveform files are processed with the aid of the Arbitrary Waveform Generator (ARB),
see
​
chapter 5.8.4, "Arbitrary Waveform Generator ARB" , on page 323.
Internally the "Multi Carrier CW" menu for defining multi carrier waveforms is available
(see
​
chapter 5.8.5, "Multi Carrier Continuous Wave" , on page 370).
5.8.2.1 Internal PRBS Data and Data Patterns
PRBS generators deliver pseudo-random binary sequences of differing length and dura-
tion. They are known as maximum length sequences, and are generated with the aid of
ring shift registers with feedback points determined by the polynomial.
By way of example, the diagram below shows a 9-bit generator with feedback to registers
4 and 0 (output).
Fig. 5-19: 9-bit PRBS generator
Baseband Signal - Baseband Block