Importance of Preserving Correlations in Error-Vector-Magnitude Uncertainty

Correlations between measurement records, e.g. frequencies or time records, are an important consideration in the uncertainty analysis of high-frequency electronic systems. To study the importance of preserving correlations, we introduce a method to scramble the correlations of a correlated uncertainty analysis and develop a software tool to do this as part of the NIST Microwave Uncertainty Framework. We then compare the results of a correlated uncertainty analysis and the corresponding scrambled analysis in estimating the uncertainty in the Error-Vector-Magnitude of a modulated signal. This comparison shows that preserving these correlations is critical to accurately assessing system performance and uncertainty.