Instrument Function
R&S
®
SMBV100A
236
Operating Manual 1407.6062.32 ─ 08
I/Q modulation with an external analog I/Q signal is possible for the basic unit (R&S SMBV
with frequency option R&S SMBV-B10x) without additional equipment options.
Baseband signals to be generated by an arbitrary waveform generator the instrument
can be equipped with an ARB module (option R&S SMBV-B50/-B51).
The basic equipment configuration for generating an internal baseband signal includes
the option R&S SMBV-B10 (Baseband Generator and ARB Module).
The external signal is input via the I and Q connector and transferred directly to the I/Q
modulator (I/Q Mod function block). Externally generated realtime baseband signals can
be fed into the digital signal path via the digital interface (digital signals) (Option R&S
SMBV-K18, Baseband Input). The external digital signal is configured in the "BB In/
Out" function block (see
chapter 5.9, "External Baseband Signal - Baseband
The internally generated baseband signal is configured in the Baseband function block
(see
chapter 5.8, "Baseband Signal - Baseband Block"
, on page 271). Before the signal
is fed into the I/Q modulator, noise can be added and/or the signal can be impaired.
Impairment at this point along the signal flow is offered to allow a signal to be output at
the I/Q-OUT outputs (a signal which, for example, compensates signal distortion in a
connected test object (DUT)).
Impairment is integrated in the basic unit. The generation of noise requires the option
R&S SMBV-K62 (AWGN).
Impairments can also be set in the I/Q Mod menu to allow an externally applied analog
I/Q signal to be impaired. An internal baseband signal can thus be impaired both digital
(in the Impairment block in the Impairment menu) and analog in the I/Q modulator. If
impairments are set in both menus, they superimpose each other in the signal.
5.5.1 I/Q Modulator
To select the input signal of the I/Q modulator and to open the "I/Q Settings" menu, select
"I/Q Mod > Configure".
The "I/Q Settings" menu containing the modulation settings is opened in the top section
(see
chapter 5.5, "I/Q Modulation - I/Q Mod Block"
I/Q Modulation - I/Q Mod Block
Summary of Contents for SMBV100A
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