Uncertainty of material measurements at microwave frequencies

This paper presents the real time uncertainty methodology developed at Keysight to compute material parameters at microwave and millimeter wave frequencies. Our approach is based on S parameter measurements applied to the classical Nicolson-Ross-Weir inversion problem, where a fully correlated uncertainty propagation is adopted to compute the uncertainty of parameters such as
$\epsilon_{r}$
and
$tan\delta$
. The methodology has been fully integrated in a simple to use application which allows real time measurement and display of the data with uncertainty.