The equipment connections are as shown in the diagram below. A mixer may be necessary if you want to convert the RF frequencies to desired IF frequencies. In case you do not need a frequency mixer, simply connect the IF OUT cable to the Noise Source, and calibrate.
It is possible that you use any connector adapters or attenuators during the measurement process to ensure that the measured values are within the range of the Noise Figure Analyzer. In such case, you may to include the adapters or attenuators during the calibration process itself (not shown in the figure).
d. Factors that you need to consider when choosing equipment for Noise Figure measurement:
Expected Noise Figure: NF Analyzer is suitable to measure Noise Figure when the value is small (say less than 10dB typical). If you intend to measure very high value or very low value (say less than 0.05dB), you may need to consult the manufacturer for suitability of the equipment.
Due to the limitations of the DUT/NF Analyzer, you may need to use external mixer for measuring NF. In such an event, ensure that the NF Analyzer supports external/internal mixer capabilities.
DUT Connectors: Some times, the DUT may have different connectors, such as waveguide. If so, you may need to procure appropriate waveguide to co-axial adapter. Most of the NF Analyzers use only co-axial connector for interconnectivity.
Gain Measurement: Normally, you measure gain along with NF. Ensure that the NF Analyzer is capable of measuring expected range of DUT Gain.
For frequency conversion, you may require external frequency generator, and a mixer. Most measurement (such as Up/Down Converters) require external frequency generator.
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