Algorithms for active noise control

Abstract

The previous regulations about acoustics in buildings ruled only isolation, forgetting other important subjects. The new code in Spain, specifically the DB-HR document, also include the regulations of excessive noise reverberating that produces and causes discomfort in many cases non-speech intelligibility, this circumstance is crucial in certain areas. The passive control restrictions in these limits of frequencies are well known. The insulating materials, soundwalls, acoustic filters, Helmholtz resonator, expansion chamber, the encapsulation of the noise source, mean large dimensions and/or weight to 500 Hz or less. The active noise control (ANC Active Noise Control) can be used to cancel the noise to high-frequency and the passive techniques can be used to low-frequency. This paper presents algorithms for active noise control and the typical industrial applications. © 2009 Springer Berlin Heidelberg.