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arXiv · 2305.18551

Multi-Band Acoustic Monitoring of Aerial Signatures

Andrew Mead·Sarah Little·Paul Sail·Michelle Tu·Wesley Andrés Watters·Abigail White·Richard Cloete
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Abstract

The Galileo Project's acoustic monitoring, omni-directional system (AMOS) aids in the detection and characterization of aerial phenomena. It uses a multi-band microphone suite spanning infrasonic to ultrasonic frequencies, providing an independent signal modality for validation and characterization of detected objects. The system utilizes infrasonic, audible, and ultrasonic systems to cover a wide range of sounds produced by both natural and man-made aerial phenomena. Sound signals from aerial objects can be captured given certain conditions, such as when the sound level is above ambient noise and isn't excessively distorted by its transmission path. Findings suggest that audible sources can be detected up to 1 km away, infrasonic sources can be detected over much longer distances, and ultrasonic at shorter ones. Initial data collected from aircraft recordings with spectral analysis will help develop algorithms and software for quick identification of known aircraft. Future work will involve multi-sensor arrays for sound localization, larger data sets analysis, and incorporation of machine learning and AI for detection and identification of more types of phenomena in all frequency bands.

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Andrew Mead, Sarah Little, Paul Sail, Michelle Tu, Wesley Andrés Watters, Abigail White, Richard Cloete. 2023-05-29. Multi-Band Acoustic Monitoring of Aerial Signatures. https://doi.org/10.1142/s2251171723400056

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