Rohde & Schwarz SMBV100A, Руководство по эксплуатации

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Instrument Function
R&S
®
SMBV100A
303 Operating Manual 1176.8016.02 ─ 17
Selecting the menu item "I/Q Impairments (Digital Baseband)..." opens the I/Q impair-
ment settings dialog. This dialog covers the settings for I/Q impairment, like carrier
leakage, imbalance and quadrature offset.
To access the AWGN settings, select "AWGN...". This dialog contains the settings of
the AWGN generator, noise level configuration and CW interfering parameters.
Selecting the menu item "I/Q Out Settings" opens a dialog with the parameters for the
I/Q output signal.
The single ended or differential output is configured in the "I/Q Out Settings" dialog.
5.7.1 Impairments
Signal impairments ( I/Q Impairments ) are well-defined arithmetic modifications of the
data. Every data sample is modified in the same way.
Impairment of the digital I/Q signal can be used to:
●
compensate the distortion of a test object
●
check the effect of a disturbed signal on a test object
●
if the internal compensation of signal distortion is deactivated by the I/Q modulator,
also to test its own baseband components.
In addition to impairment of the digital I/Q signal, the R&S SMBV also allows impair-
ment of the analog signal to be set in the I/Q modulator. The relevant settings are
made in the I/Q Mod function block (see
Chapter 5.6, "I/Q Modulation - I/Q Mod Block" ,
on page 296).
5.7.1.1 Gain and Gain Imbalance
An I/Q gain is a multiplication of all I/Q amplitudes by a common factor. The effect is
equivalent to two identical I and Q gain factors. The effect of an increased gain factor
in the I/Q constellation diagram is shown on
Figure 5-13 .
Impairment of Digital I/Q Signal and Noise Generator - AWGN/IMP Block