R&S SMJ100A, Operating Manual

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Instrument Function
R&S
®
SMJ100A
338 Operating Manual 1403.7458.32 ─ 14
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A "Cut Off Frequency Shift" = -1 results in a very narrow-band filter
●
Increasing the value up to 1 makes the filter more broad-band
●
By "Cut Off Frequency Shift" = 0, the -3 dB point is at the frequency determined by
the half of the selected "Sample Rate".
User filter
The user filter file must have extention
*.vaf
and can be created with the R&S filter
wizard.
The filter wizard (filtwiz) is a tool from Rohde & Schwarz designed for creating filter
files that can be imported on a R&S
SMJ. Its main purpose is the conversion of user-
defined finite impulse response (FIR) filters into the filter format (
*.vaf
). Beyond this
filtwiz provides designs for standard filters, e.g. Root Raised Cosine, Gaussian.
The program was developed on a 32-bit Microsoft Windows platform under MATLAB.
For more information, refer to the description "Introduction to "filtwiz" Filter Editor" on
the Rohde&Schwarz Internet page.
5.8.2.5 Conflicting Settings - Custom Digital Mod
Having selected a modulation procedure, not every combination is possible when
selecting the settings for the modulation parameters "Symbol Rate" and "Coding".
These restrictions inevitably give rise to conflicting settings if a parameter is changed
and leads to a prohibited combination.
A conflicting setting is indicated by a message on the Info line in the display. The
R&S
SMJ displays the setting entered by the user, but the modulation signal actually
generated does not correspond to this display. A conflict of settings can be triggered if
the user changes a parameter inappropriately. The message disappears as soon as a
conflict-free setting is entered.
A list of the possible settings conflicts and messages in digital modulation can be found
in
Chapter 9, "Status Information, Error Messages and Troubleshooting" , on page 813.
5.8.2.6 Custom Digital Mod User Interface
Baseband Signal - Baseband Block