Agilent Technologies HP 8719D Service Manual page 455

Procedures
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. Convert the S-parameters of the test device to their
absolute linear terms.
Noise Floor and Crosstalk. If a full 2-port calibration is performed, the
residual 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.
Dynamic Accuracy. Determine the absolute linear magnitude dynamic accuracy
from the dynamic accuracy graph (see Figure A-l).
Other Error lbrms. Depending on the connector type in your system,
refer to residual error specifications in the "Specifications and Measurement
Uncertainties" chapter
linear magnitude of the remaining error terms.
Combining Error 'lbrms. Combine the above terms using the reflection or
transmission uncertainty equation in the worksheets.
the
in HP 8719D/ZOD/ZZD Ndwork Anul~zer User's
Determining System Measurement Uncertainties A-8