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.

+Cpfl x f + Cpf2 x f + Dps1 + Dpfsl x f

where

Cpfl = Cable phase/frequency port 1

Cpf2 = Cable phase/frequency port 2

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.

Since this curve combines the effects of dynamic accuracy and noise, if used in uncertainty calculations, the effects of the noise terms in the corresponding equations can be eliminated.

Dynamic Accuracy (linear) = 10

fDynAcc(dB) f 1

2.

Dynamic Accuracy (dB) = 2OZog( 1 f Dynamic Accuracy (linear))

HP8753E Magnitude Dynamic Accuracy 0.3 to 3000 MHz

HP8753E Magnitude Dynamic Accuracy 3-6 GHz

-10 0 -10 -20 -30 -40 -50 -60 -70 -80 -90 -100

TestPortPower(dBm)TestPortPower(&III)

B-6 Determining System Measurement Uncertainties

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Image 667
HP 8753E manual Dynamic Accuracy, Transmission Phase Uncertainty Etp