R&S SMJ100A, Operating Manual

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Instrument Function
R&S
®
SMJ100A
314 Operating Manual 1403.7458.32 ─ 14
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Control signals
The input signals can be both internally generated and supplied from an external
source. The internally generated data and clock signals are output not only on the
DATA and CLOCK connectors but also on the corresponding pins of the AUX I/O inter-
face.
Likewise control signals and also trigger signals for triggering signal generation in the
R&S
SMJ can be internally generated or supplied from an external source.
Up to four 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 5.8.3, "Arbitrary Waveform Generator ARB" , on page 367.
Internally the "Multi Carrier CW" menu for defining multi carrier waveforms is available
(see
Chapter 5.8.4, "Multi Carrier Continuous Wave" , on page 424).
5.8.1.1 Internal PRBS Data and Data Patterns
PRBS generators deliver pseudo-random binary sequences of differing length and
duration. 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 regis-
ters 4 and 0 (output).
Figure 5-17: 9-bit PRBS generator
For PRBS15 and PRBS23, a CCITT V.52-compliant data inversion is performed in the
feedback path automatically as shown below:
The pseudo-random sequence from a PRBS generator is uniquely defined by the reg-
ister number and the feedback. The following table describes the available PRBS gen-
erators:
Baseband Signal - Baseband Block