Analog Modulations
SMIQ
1125.5555.03
E-8
2.60
2.7.2
Broadband AM (BB-AM)
In the BB-AM mode the I/Q modulator is used for amplitude modulation. Level control should be set to
AUTO or ON (see section, Switching On/Off Internal Level Control).
The modulation input (BB-AM) is identical with the I input of the I/Q modulator. The input impedance is
50
Ω
. A signal of -0.25 V to +0.25 V corresponds to an amplitude modulation of -100% to +100%.
Setting the modulation depth with BB-AM is not possible.
Notes:
-
For Broadband AM the value for the upper level limit is the same as for vector
modulation. Depending on the modulation depth, PEP can exceed the displayed value
by up to 6 dB.
-
Broadband AM cannot be selected together with normal AM or vector modulation.
These modulation deactivate one another
Menu selection:
ANALOG MOD - BB-AM
FREQ
100. 000 000 0
MHz
LEVE L
- 30.0
dBm
FREQ UENCY
LEVE L
ANAL OG MOD
VECT OR MOD
DIGI TAL MO D
DIGI TAL ST D
LF OUTPUT
SWEE P
LIST
MEM SEQ
UTIL ITIES
AM
BB-A M
FM
PM
PULS E
STATE
INPUT SENSITIVITY
OFF
ON
0.25V/100%
Fig. 2-27
Menu ANALOG MOD - BB-AM (preset setting)
STATE
Switches BB-AM on and off.
IEC/IEEE-bus command
SOUR:AM:BBAN ON
INPUT SENSITIVITY
Display of the input sensitivity. The value cannot be changed.