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arXiv · 1809.07297

Analyzing Uncertainty Matrices Associated with Multiple S-parameter Measurements

Nick M. Ridler·Martin J. Salter
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Abstract

This paper presents a detailed analysis of uncertainty matrices (i.e. measurement covariance matrices) associated with multiple complex-valued microwave scattering S-parameter measurements. The analysis is based on forming combinations of (2 X 2) sub-matrices from selected elements in the uncertainty matrix and using these sub-matrices to define uncertainty ellipses in two-dimensional measurement planes. These uncertainty ellipses can be used to assess the quality, accuracy and validity of the measurements. A simple example is given using measurements made on a waveguide mismatched line section at frequencies from 75 GHz to 110 GHz. The analysis is also useful when multiple S-parameter measurements are used as input quantities for measurement models used to determine other measurement quantities (i.e. as output quantities).

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Nick M. Ridler, Martin J. Salter. 2018-09-19. Analyzing Uncertainty Matrices Associated with Multiple S-parameter Measurements. https://doi.org/10.1109/arftg.2015.7162898

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