Keysight Technologies FieldFox A Series, User Manual

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580 Keysight N9927-90001 User’s Guide
Noise Figure Mode (Option 356 – CPU2 Only)
How to Define a Noise Figure Measurement
As in the case of the DUT, In addition to entering the magnitude reflection
coefficient values, the uncertainty calculation takes into account the
distribution (
Γ
Distribution) and specified style (Spec Style) for the
preamplifier reflection coefficient value.
— User Calibration Noise Source Reflection Coefficient, ENR Uncertainties
and ENR values (User Calibration Only):
These are identical to the noise source values entered for the measurement,
but are entered prior to performing the user calibration (Run User Cal).
— Controlling the Uncertainty Calculation and Display
For this section, see also “Overview of Softkey Menus” on page 555
( Uncertainty > Uncert Contributions on page 561 ).
When enabled, uncertainty bars are displayed on the data trace, indicating
the uncertainty range for the current Noise Figure, Noise Factor, or Noise
Temperature measurement. By default, the displayed uncertainty range is
the measured data +/- the default coverage factor of two times the
calculated standard deviation (2
σ
), which is based on all included
uncertainties. Optionally, the coverage factor may be changed to 1
σ
, 2
σ
or
3
σ
. Also, as an aid in determining the cause of measurement uncertainty,
any of the individual contributors (user calibration (User Cal Uncert),
mismatch uncertainty (Mismatch Uncert), ENR uncertainty (ENR Uncert), or
jitter uncertainty (Jitter Uncert) may be excluded from the uncertainty
analysis.