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Phase inversion and collapse of the cross-spectral function
Published
Author(s)
Craig W. Nelson, Archita Hati, David A. Howe
Abstract
Cross-spectral analysis is a mathematical tool for extracting the power spectral density of a correlated signal from two time series in the presence of uncorrelated interfering signals. We demonstrate and explain a set of conditions where the detection of the desired signal using cross-spectral fails partially or entirely in the presence of a second uncorrelated signal. Not understanding when and how this effect occurs can lead to dramatic underreporting of the desired signal. Theoretical and simulated demonstrations of this effect are presented
Nelson, C.
, Hati, A.
and Howe, D.
(2013),
Phase inversion and collapse of the cross-spectral function, Electronics Letters
(Accessed October 14, 2025)