Sources Of Measurement Errors; Sources Of Systematic Errors - HP 8719ET Reference Manual

Sources of Measurement Errors

Measurement errors are made up of systematic errors, random errors, and drift errors.
Each of these measurement error types is discussed in this section.

Sources of Systematic Errors

The residual (after measurement calibration) systematic errors result from imperfections
in the calibration standards. All measurements are affected by dynamic accuracy. For
reflection measurements, the associated residual errors are residual directivity, residual
source match, residual load match, and residual reflection tracking. For transmission
measurements, the additional residual errors are residual crosstalk, residual source
match, residual load match, and residual transmission tracking.
The listing below shows the abbreviations used for residual systematic errors that are in
the uncertainty equations.
• E = forward residual directivity
DF
• E = forward residual source match
SF
• E = forward residual reflection tracking
RF
• E = forward crosstalk
XF
• E = forward load match
LF
• E = forward transmission tracking
TF
• E = reverse residual directivity
DR
• E = reverse residual source match
SR
• E = reverse residual reflection tracking
RR
• E = reverse crosstalk
XR
• E = reverse load match
LR
• E = reverse transmission tracking
TR
• A = magnitude dynamic accuracy
M
• A = phase dynamic accuracy
P
Dynamic accuracy includes errors during internal self-calibration routines, gain
compression in the microwave frequency converter (sampler) at high signal levels, errors
generated in the synchronous detectors, localized non-linearities in the IF filter system,
and from LO leakage into the IF signal paths.
Determining System Measurement Uncertainties
Sources of Measurement Errors
10-3