Extended Method of Estimation Uncertainties of Indirect Multivariable Measurements on the Twoport Example (original) (raw)
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Advances in Intelligent Systems and Computing, 2020
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Journal of Physics: Conference Series, 2018
Signal processing in a multi-variable indirect measurement system and its uncertainties is considered. It was proposed to extend the vector method of estimating uncertainties, given in Supplement 2 to GUM for the use to describe the accuracy of instrumental systems for indirect multivariable measurements. A formula for the covariance matrix of relative uncertainties is also given. As the example, the covariance matrix for indirect measurements of the star form circuit resistances from its terminals was determined and influence of of the measurement channels uncertainties are analyzed.
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IEEE Transactions on Microwave Theory and Techniques, 2000
Two-port vector network analyzers can be used for measuring differential circuits by integrating baluns. However, due to the imperfection of the baluns, measurement uncertainties occur even under the most accurate calibration conditions. These uncertainties are caused by the common and cross modes of the baluns and the device-under-test. This paper proposes a new algorithm, which evaluates these measurement uncertainties, by using a few sets of assumptions that can approximately correspond to the worst conditions in which the common and cross modes maximally affect the measurements. The proposed algorithm can be used in post measurement processes by which the users can be informed of their measurements' uncertainties.