Industrial sound source localization using microphone arrays under difficult meteorological conditions

Source localization using microphone arrays has now become common practice for many applications. Their application for long term monitoring of industrial noise nevertheless remains uncommon. Hence, in 2016 we deployed four microphone arrays near a large industrial area for a period of 12 months and explored the challenges involved. The difficult meteorological conditions leading to strongly varying attenuations, 3D refraction, and scattering turned out to be one of these major challenges. Changes in source locations and estimated source power are quite often the result of abrupt changes in local weather conditions. Notwithstanding the careful weather monitoring, assumptions and hypotheses on the sources' temporal behavior and spectra combined with a statistical locator were still needed to obtain satisfactory results. Validation of the proposed approaches on a known source with stable noise emission over time is presented in the paper.