Rohde & Schwarz ZNB20, User Manual

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GUI Reference
R&S
®
ZNB/ZNBT
395 User Manual 1173.9163.02 ─ 38
Each conversion factor is ratio of two integer numbers. The frequency-converting
device is considered to be part of the mixer system under test (MUT). In the default
configuration where the RF signal is swept and the LO signals are at fixed frequency,
the conversion factors do not modify the analyzer's source signals (RF, LO 1, LO 2);
they are used for the calculation of the IF frequency only.
Remote command:
[SENSe<Ch>:]FREQuency:CONVersion:MIXer:RFMultiplier
[SENSe<Ch>:]FREQuency:CONVersion:MIXer:LOMultiplier<Stg>
2nd Mixer
Selects the measurement for a test setup including two mixers (instead of a single
one); see
Two-Stage Mixer Measurements . The signal diagram and the other control
elements in the dialog are adjusted accordingly.
Remote command:
[SENSe<Ch>:]FREQuency:CONVersion:MIXer:STAGes
Conversion
Selects the frequency of the IF signal.
The output signal (IF signal) of each mixer can be at the sum or at the difference of the
RF and LO input frequencies.
●
IF = RF – LO means that the RF signal is down-converted (upper sideband). The
analyzer automatically switches to IF = LO – RF if the LO frequency is above the
RF input frequency.
●
IF = LO – RF means that the LO signal is down-converted (lower sideband). The
analyzer automatically switches to IF = RF – LO if the RF input frequency is above
the LO frequency.
●
IF = LO + RF means that the RF input signal is up-converted.
To perform measurements at different mixer output frequencies (e.g. to analyze the
isolation for IF = RF or higher-order mixing products), use the "Define Port Settings"
dialog (see
Chapter 5.5.2.2, "Port Settings Dialog" , on page 361).
The basic formulas described above are adjusted to the mixer measurement settings:
●
If the RF or one of the LO signals is in Auto mode (instead of IF), the formulas
above are automatically converted. Example: LO 1 in Auto mode, down-conversion
(lower sideband) --> LO 1 = IF + RF.
●
IF = LO – RF means that the LO signal is down-converted (lower sideband). The
analyzer automatically switches to IF = RF – LO if the RF input frequency is above
the LO frequency.
●
If two mixer stages are present, the conversion formulas are applied twice; see
Two-Stage Mixer Measurements .
Remote command:
[SENSe<Ch>:]FREQuency:CONVersion:MIXer:TFRequency<Stg>
Generators...
Opens the configuration dialog for external generators; see Chapter 5.19.4.4, "External
Generators Dialog" , on page 625. Configured generators appear in the port selection
lists for the LO signals.
Channel Config Softtool