Can Noise Figure measurement support non-NI SMU as the power supply of noise source

Updated Jul 29, 2026

Issue Details

I am performing a Noise Figure (NF) measurement using the Y-factor method in RFmx SpecAn. The documentation indicates that a Source Measure Unit (SMU) can be used to power the noise source, but I would like to know whether a third-party(non-NI) power supply can be used instead of an NI SMU?
Below is the screenshot of configure NI SMU in InstrumentStudio.

Solution

No, RFmx SpecAn and InstrumentStudio support only NI Source Measure Units (SMUs) when automatic control of the noise source power supply is required for Y-factor Noise Figure (NF) measurements. The reason is underlying driver uses niDCpower driver to control SMU(Source Measurement Unit).
  • Verify that the NF measurement is configured to use External Noise Source as the noise source type.
  • Use a supported NI SMU as the noise source power supply.
  • Configure the SMU resource through the RFmx setup string by using the NoiseSourcePowerSupply specifier.
  • Allocate a dedicated SMU channel for RFmx control.

Below screenshot can be reference.

Related Links

https://www.ni.com/docs/zh-CN/bundle/rfmxspecan-labview-api-ref/page/resource/objmgr/rfmxspecan-rc/rfmxspecan/attr120041.html

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