Analysis of noise parameters extraction from noise figure measurements

Noise characterization of active devices continues to be an area of increasing significance in the rapidly expanding field of RF wireless communications. The accuracy of noise parameter estimation is a challenging task, limited by the uncertainties in the noise (noise source and noise figure) measurements, the errors in the source admittance (reflection coefficient) data and the losses on either side of the Device Under Test (DUT). In this paper, a qualitative and graphical assessment is made of the sensitivities and estimation errors of the noise parameters over the two-dimensional region encompassing the source admittance (G(S),B-S) grid. This analysis is carried out with the objective of locating stable (where the estimation error is low) and unstable (where the estimation error is high) regions on the admittance grid.