Agilent Technologies HP 8719D Service Manual page 453

The detailed equation for each of the above terms is derived from the signal
flow model, located at the end of this appendix.
Transmission Phase Uncertainty (Etp)
Transmission phase uncertainty is calculated from a comparison of the
magnitude uncertainty with the test signal magnitude. The worst case phase
angle is computed. This result is combined with the error terms related to phase
dynamic accuracy, cable phase stability, and thermal drift of the total system.
where
Cpfl = Cable phase/frequency port 1
Dpsl = drift phase/degree source to port 1
Dpfsl = drift phase/degree/frequency source to port 1
Dynamic Accuracy
On the following page is a typical dynamic accuracy and noise curve for the
analyzer. This curve is based on statistical samples of units built at the factory
with an IF BW of 10 Hz.
uncertainty calculations, the effects of the noise terms in the corresponding
equations can be eliminated.
Dynamic Accuracy (linear) =
Dynamic Accuracy (dB) = 2Olog(
1
+ Cpf x f + Cpf2 x f + Dpsl + Dpfsl x f
10
1
Determining System Measurement Uncertainties A-7