Rohde & Schwarz SMBV100A, Руководство пользователя

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Instrument Function
R&S
®
SMBV100A
272 Operating Manual 1407.6062.32 ─ 08
5.8.1 Working with the Baseband Signal
Frequency and phase offset are defined at the topmost menu level in the "Baseband"
block or by using the MENU button under "Baseband".
The upper part of the "Baseband" dialog is used for selecting digital standards, digital
modulation and waveform generation. These menus are described in the respective
chapters relating to the modulation systems.
The lower part of the "Baseband" dialog can be used to define a frequency and phase
offset.
Frequency Offset
Enters the frequency offset for the baseband signal.
The frequency offset shifts the baseband frequency interval and provides a quick way to
shift the used frequency band in the RF frequency section without modifying the RF set-
tings.
Wenn a frequency offset is defined, an icon is displayed in the signal flow right to the
baseband block.
The complex I/Q bandwidth of the shifted useful signal must not exceed 120 MHz (R&S
SMBV with option B10/B50) or 60 MHz (R&S SMBV with option B51) in total.
The following applies:
f
offset
- f
use
/2 >= - 120MHz/2 and f
offset
+ f
use
/2 <= + 120MHz/2
f
use
= the complex useful bandwidth of the I/Q signal before the offset.
f
offset
= frequency offset.
The following graph illustrates the setting range for the frequency offset.
Fig. 5-17: Setting range for frequency offset
Baseband Signal - Baseband Block