Rohde & Schwarz SMB 100a - Phase Modulation - Phim

Phase Modulation - PhiM R&S SMB
1407.0806.32 4.68 E-2
FM Ext Coupling
(Source External only)
Selects the coupling mode (AC or DC) for external feed.
Note:
Coupling for external feed via input MOD EXT is set for all
modulations with external source.
AC
The d.c. voltage content is separated from the
modulation signal.
Remote-control command:
SOUR:FM:EXT:COUP AC
DC
The modulation signal is dc-coupled.
Remote-control command:
SOUR:FM:EXT:COUP DC
LF Gen Freq - FM
(Source Internal)
Sets the frequency of the LF generator.
Remote-control command:
SOUR:LFO:FREQ 1E3
LF Gen Shape - FM
(Source Internal, LFGen2 only)
Selects the shape of the second LF generator.
Remote-control command:
SOUR:LFO:SHAP SQU
Phase Modulation - PhiM
An internal and/or external source can be selected for phase modulation. A LF modulation generator is
available as internal sources.
The MOD EXT input connector for external feed of analog modulation signals is at the front of the
instrument. The coupling mode of the input (AC or DC) can be selected.
Selection between three modulation modes is possible:
- Normal mode with full setting range for modulation bandwidth and PhiM deviation.
- Low Phase noise mode with better signal/noise ratio, but reduced setting range for modulation
bandwidth and deviation (see data sheet)
- High Deviation mode with full setting range for PhiM deviation and a reduced setting range for
modulation bandwidth. Phase noise is reduced in the lower modulation frequency range (compared
to Normal mode).
Note:
It is not possible to use phase modulation simultaneously with frequency modulation.