Karolina Prawda, Sebastian J. Schlecht and Vesa Välimäki
Companion page for a paper published in the Journal of the Acoustical Society of America
Cite as: Karolina Prawda, Sebastian J. Schlecht, and Vesa Välimäki, "Robust selection of clean swept-sine measurements in non-stationary noise", The Journal of the Acoustical Society of America 151, 2117-2126 (2022), doi: https://doi.org/10.1121/10.0009915
The exponential sine sweep is a commonly used excitation signal in acoustic measurements. It is, however, susceptible to non-stationary noise. This paper shows how to detect contaminated sweep signals and select clean ones based on a procedure called the rule of two, which analyzes repeated sweep measurements. A high correlation between a pair of signals indicates that they are devoid of non-stationary noise. The detection threshold for the correlation is determined based on the energy of background noise and time variance. A median-based method is suggested for reliable background noise energy estimation, as it is not disturbed by non-stationary events. The proposed method is shown to detect reliably 95% of impulsive noises and 75% of dropouts in the synthesized sweeps. The proposed method is tested on a large set of measurements and is compared with a previous method showing that it is more robust in detecting various non-stationary disturbances, improving the detection rate by 30 percentage points. The rule-of-two procedure increases the robustness of practical acoustic and audio measurements.
Audio player: Werner, Nils, et al. "trackswitch.js: A Versatile Web-Based Audio Player for Presenting Scientifc Results." 3rd web audio conference, London, UK. 2017.