R&S
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ZVA / R&S
®
ZVB / R&S
®
ZVT GUI Reference
Channel Menu
Operating Manual 1145.1084.12 – 30 362
ranges mentioned above will be calibrated both in the RF and IF range if the Two Tone Output is set to
Port 1, and in the IF range only if the Two Tone Output is set to Ext. Dev.
[SENSe<Ch>:] CORRection:COLLect:IMODulation[:STATe]
Reset Frequency Conv and Intermod
This softkey disables the intermodulation measurement mode and switches back to normal (non
frequency-converting) mode.
[SENSe<Ch>:]FREQuency:IMODulation:CONVersion OFF
Noise Figure Measurement (R&S ZVA and R&S ZVT)
The Noise Figure Meas submenu controls the measurement of the noise figure of a DUT. This
measurement requires option R&S ZVAB-K30.
Noise figure measurements
The noise figure of a device is the ratio of the output signal-to-noise ratio (SNR) to the input SNR,
provided that a thermal noise signal is fed to the input. It is a measure of the degradation of the SNR
caused by the device.
The purpose of the Noise Figure Meas is to assess the noise figure of a DUT which operates in its linear
range. A typical example is an amplifier which is measured in transmission. The method of measurement
offers several advantages:
No additional noise source is required.
The result can be obtained in a single sweep.
The test setup is as simple as for a basic transmission measurement: The DUT must be
connected only once. Moreover, it is possible to perform S-parameter measurements in parallel to
the noise figure measurement.
Noise figure measurements can be performed irrespective of the sweep type: A frequency sweep yields
the noise figure as a function of the frequency, a power sweep yields the power-dependent noise figure at
fixed frequency. See also Basic Test Setup and Noise Figure Calculation.
Refer to application note 1EZ61 for a detailed discussion of the noise figure measurement including
many examples.
Mixer noise figure measurements
With option R&S ZVA-K31 (in addition to options R&S ZVAB-K30 and R&S ZVA-K4), R&S ZVA and R&S
ZVT network analyzers can determine the noise figure of a mixer or of a system of two mixer stages. In
analogy to the noise figure for non-frequency-converting two-port devices, we define the mixer noise figure
as the ratio of the signal-to-noise ratio (SNR) at the mixer's IF output to the SNR at its RF input, provided
that a thermal noise signal is supplied. This definition implies an important approximation; it neglects a
possible effect due to the noise of the LO signal(s).
Mixers in general convert two different RF frequencies to the same IF frequency. The second RF
frequency (or frequency band) is referred to as image frequency. The image band contributes to the
mixer's noise figure unless its reception is excluded by constructive measures, e.g. filters. The mixer noise
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