Active noise control

Details Active noise control Active noise control

1989-04-25

1990-10-23

Isen, Forester W.

Electrical audio signal processing systems and devices

Acoustical noise or sound cancellation

Adjacent ear

G10K 1116

Patent

active

049658328

ABSTRACT:
An active noise control system for controlling noise propagated through a duct comprises a first microphone located to receive the propagated noise at a point in a plane perpendicular to the length of the duct. A loudspeaker is located substantially at that plane for introducing sound into the duct. An analog first control circuit is operative in response to the noise received by the first microphone to feed a signal to the loudspeaker such that the sound introduced thereby destructively interferes with the noise at that point. A second microphone is located further downstream to receive residual noise propagated along the duct despite the destructive interference. A second control circuit, responsive to the residual noise received by the second microphone, controls parameters of the analog first control circuit so as to minimize the residual noise. In particular, the first control circuit includes an integrator which has a transfer function which is electrically controlled by the second control circuit.

REFERENCES:
patent: 4677676 (1987-06-01), Eriksson

Affiliated with

Also associated with

Rating

Active noise control does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Active noise control, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Active noise control will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-772443