Rohde & Schwarz 1145.1010.04/05/06, Руководство по эксплуатации

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R&S
®
ZVA/ZVB/ZVT Channel Menu
1145.1084.12 4.173 E-6
Mixer Measurements
RF mixers convert an RF signal at one frequency into a signal at another frequency. The frequency that
is to be shifted is applied at the RF input and the frequency shifting signal (from a local oscillator, LO) is
applied to the RF mixer's LO port, resulting in an output signal at the mixer's Intermediate Frequency
(IF) port.
For a given RF signal, an ideal mixer would produce only two IF outputs: one at the frequency sum of
the RF and LO (IF = RF + LO), and another at the frequency difference between the RF and LO (IF =
|RF – LO|). Filtering can be used to select one of these IF outputs and reject the unwanted one.
In the mixer mode the analyzer provides the following functionality:
•
Configuration of the RF and LO signals and measurement of the generated IF signal, see
Define Mixer Mode and Mixer Signal Diagrams .
•
Power calibration of the signal sources and of the IF receiver; see Mixer Power Calibration .
•
The mixer mode can be used also to test important performance parameters of RF mixers such
as frequency ranges, conversion loss, compression, and isolation.
•
Mixer Meas and Freq Conv Off toggle between the (frequency-converting) mixer mode and
normal (non frequency converting) operation.
•
Define Mixer Meas... opens a dialog to configure the mixer input signals.
•
Mixer Power Cal... opens a dialog to perform a power calibration of the signal sources and of
the IF receiver.
Mixer Meas, Freq Conv Off
The two softkeys Mixer Meas and Freq Conv Off toggle between the (frequency-converting) mixer mode
and normal operation, where the analyzer measures the unconverted fundamental wave.
Freq Conv Off also disables an active harmonic distortion measurement. A Mix label in the channel list
indicates that the mixer mode is active.
Remote control: [SENSe<Ch>:]FREQuency:CONVersion MIXer | FUNDamental