active sound reduction system for attenuation of sound from a primary sound source and active sound reduction method for attenuation of sound from a primary sound source

摘要

The present invention refers to an active sound reduction system and method for attenuation of sound emitted by a primary sound source, especially for attenuation of snoring sounds emitted by a human being. This system comprises a primary sound source, at least one speaker as a secondary sound source for producing an attenuating sound to be superposed with the sound emitted by said primary sound source, a reference microphone for receiving sound from said primary sound source, and at least one error microphone being allocated to each speaker to form a speaker/microphone pair. The at least one error microphone is provided as a directional microphone pointing at its allocated speaker to receive residual sound resulting from the superposition of the sounds from the primary sound source and the corresponding speaker. The error microphone and speaker of at least one speaker/microphone pair and the primary sound source are arranged substantially collinear. A control unit is provided to receive an output reference signal of the reference microphone representing the sound received by the reference microphone and an output error signal of the at least one error microphone representing the sound received by the at least one error microphone and to calculate a control signal for the speaker from the output reference signal and the output error signal.