Active control of scattered acoustic radiation: a real-time implementation

Emmanuel Friot; Régine Guillermin; Muriel Winninger

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Active control of scattered acoustic radiation: a real-time implementation

Emmanuel Friot·Régine Guillermin·Muriel Winninger

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Abstract

This paper presents an active noise control experiment designed to validate a real-time control strategy for reduction of the noise scattered from a three-dimensional body. The control algorithm relies on estimating the scattered noise by linear filtering of the total noise measured around the body; suitable filters are identified from off-line measurements. A modified Filtered-Error Least-Mean-Squares algorithm then leads to the adaptive filters which drive the secondary sources. The paper provides the numerical simulations using a Boundary Element Method which helped in designing a feasible experiment in an anechoic chamber with a limited number of control sources. Eventually a real-time pure-tone implementation with 14 ordinary loudspeakers and a large body is shown to yield on average a 10 dB reduction of the scattered noise at the error sensors, which is close to the optimum reduction predicted by the numerical simulations for the sensor arrangement.

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Emmanuel Friot, Régine Guillermin, Muriel Winninger. 2005-11-18. Active control of scattered acoustic radiation: a real-time implementation. https://arxiv.org/abs/physics/0511164

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