Agilent Technologies 85025A, User'S And Service Manual, Page: 42 / 98

the sources of measurement uncertainty will be required. An error analysis of
the sources of measurement uncertainty follows .
T able 4-5.
Approximate Error Analysis at 18 GHz for 85025A/B/E
Detectors
Uncertainty 85025A
Option 001
85025A 85025B 85025E
P ower Sensor CAL F actor Uncertainties
(RSS)
1.5% 1.5% 1.5% 1.5%
Mismatch between Attenuator and P ower
Sensor
5.2% 3.8% 2.1% 2.4%
Mismatch between Attenuator and Detector 5.9% 4.2% 3.3% 1.5%
Miscellaneous System Errors 1.1% 1.1% 1.1% 3.2%
RSS Calculation 8.1% 6.0% 4.3% 4.5%
T otal RSS Uncertainties Expressed in dB +0.34 to 00.37 +0.25 to 00.27 +0.18 to 00.19 +0.19 to 00.20
T able 4-6.
Approximate Error Analysis for the 85025D Detector
Uncertainty 26.5 GHz 40 GHz 50 GHz
P ower sensor CAL factor approximate
uncertainties
1.5% 2% 2.5%
Mismatch between attenuator and power
Sensor
1.3% 3.8% 7.4
Mismatch between attenuator and detector 1.4 4.2 14.3
Miscellaneous system errors 1.1% 1.1% 1.1%
RSS calculation 2.7% 6.1% 16.3%
T otal RSS uncertainties expressed in dB +0.12 to 00.12 +0.26 to 00.27 +0.64 to 00.76
Uncertainties are smaller at lower frequencies . The error analysis is done
assuming the power sensor , attenuator , and DUT all mate without the use of
adapters . A standard 85025A is used with an 8481A and 8491B . An 85025A
Option 001 detector is used with an 8481A Option 001 and 8492A . The
85025B/E is used with an 8485A and 8493C. The 85025D is used with an 8487A
and 8490D .
4-10 P erformance T ests Agilent 85025A/B/D/E