Rohde & Schwarz SMM100A, Руководство пользователя

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Configuring the internal baseband source
R&S
®
SMM100A
259 User Manual 1179.1341.02 ─ 05
To observe the effect of offsetting the frequency
Use the built-in real-time graphical display ("System Configuration > Graphics > Power
Spectrum") and observe the power spectrum of the signal with and without frequency
offset:
●
Chapter 3.3.5, "Verifying the generated signal with the graphics display" ,
on page 58
●
See "To set and verify a baseband frequency offset" on page 436.
4.12.1.2 Impact of the phase offset
The "Phase Offset" determines the phase offset between the different baseband sig-
nals. A phase offset rotates each point of an I/Q constellation diagram by the specified
phase offset.
Figure 4-30: I/Q constellation diagram: Effect after offsetting the phase by an angle of 45
°
To observe the effect of offsetting the phase
Use the built-in real-time graphical display ("System Configuration > Graphics > Con-
stellation") and observe that the points on the I/Q constellation diagram are turning
counterclockwise.
See Chapter 8.1, "Displaying baseband signal characteristics in real-time" ,
on page 421.
4.12.2 Baseband offsets settings
Access:
► Select "Baseband > Baseband Offsets" or "BB Input > Baseband Offsets".
The "Baseband Offsets" dialog provides the settings necessary to add frequency
and/or phase offset.
Shifting and boosting the baseband signal