HP 8753E User Manual page 668

Determining Expected System Performance
Use the uncertainty equations, dynamic accuracy calculations in this appendix, and tables of
system performance values from the "Specifications and Measurement Uncertainties" chapter
in the HP 87533 User's tiide to calculate the expected system performance. The following
pages explain how to determine the residual errors of a particular system and combine them
to obtain total error-corrected residual uncertainty values, using worksheets provided. The
uncertainty graphs in the user's guide are examples of the results that can be calculated using
this information.
Use the measurement uncertainty worksheet to calculate the residual uncertainty in
transmission and reflection measurements. Determine the linear values of the residual error
terms and the nominal linear S-parameter data of the device under test as described below
and enter these values in the worksheets Then use the instructions and equations in the
worksheets to combine the residual errors for total system uncertainty performance. The
resulting total measurement uncertainty values have a confidence factor of 99.9%.
S-parameter
Values.
terms.
Noise Floor and Crosstalk.
term can be ignored. Connect an impedance-matched load to each of the test ports and
measure S21 or S12. Use the statistic function to measure the mean value of the trace. Use
this value plus one standard deviation as the noise floor value of your system.
Determine the absolute linear magnitude dynamic accuracy from the
Dynamic Accuracy.
dynamic accuracy graph on the previous page.
Other Error
specifications in the "Specifications and Measurement Uncertainties" chapter in the HP 87533
User's Guide, and the "Characteristic values 'Iable" in this chapter to find the absolute linear
magnitude of the remaining error terms.
Combining Error
uncertainty equation in the worksheets.
Convert the S-parameters of the test device to their absolute linear
If a full 2-port calibration is performed, the residual crosstalk
Determining System Measurement Uncertainties B-7