EXTENDED METHOD OF ESTIMATION UNCERTAINTIES OF INDIRECT MULTIVARIABLE MEASUREMENTS ON THE TWOPORT EXAMPLE

The new extended mathematical model for evaluation uncertainties of indirect multivariable measurements, which upgrades the method given in Supplement 2 of guide GUM, is presented. In this model the uncertainties and correlations of parameters of the processing function are taken also into account. This model can be used for multivariable measurements and to describe the accuracy of instruments and systems that perform such measurements. The estimation of uncertainties of voltage and current on the output of a twoport network from indirect measurements on its input with considering influences the uncertainties of twoport  elements is included.