Active noise control system for attenuating engine generated noi

Electrical audio signal processing systems and devices – Acoustical noise or sound cancellation – Adjacent ear

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

A61F 1106, H03B 2900

Patent

active

053217594

ABSTRACT:
An active noise control (ANC) system is disclosed for attenuating engine generated noise that contains at least one sinusoidal noise component having an amplitude and frequency that vary with changes in engine rotational speed. The ANC system includes a means for generating at least one generator output signal that contains one or more sinusoidal signal components, where the frequency of each signal component corresponds to the frequency of a respective noise component. A separate control signal having an amplitude that varies with engine rotational speed is generated to correspond with each generator output signal. Each generator output signal is then multiplied by its respective control signal to produce a corresponding filter input signal. Each filter input signal passes to a respective adaptive filter, where it is filtered to produce a corresponding filter output signal according to the adjustable filtering characteristics of the adaptive filter. Noise canceling waves are generated by a noise canceling actuator in response to each filter output signal, and the canceling waves are superimposed with the undesirable noise generated by the engine. The level of residual noise resulting from this superposition is sensed, and an error signal is developed to represent the residual noise level. The filtering characteristics of each adaptive filter are adaptively adjusted based upon the error signal to minimize the residual noise level. In the preferred embodiment, each control signal has its amplitude determined in accordance with a respective predetermined function based upon the sensed engine rotational speed, and each predetermined function is correlative of the amplitude behavior of those noise components corresponding to the signal components contained in the generator output signal that is multiplied by the respective control signal.

REFERENCES:
patent: 4480333 (1984-10-01), Ross
patent: 4506380 (1985-03-01), Matsui
patent: 4683590 (1987-07-01), Miyoshi et al.
patent: 4689821 (1987-08-01), Salikuddin et al.
patent: 4805733 (1989-02-01), Kato et al.
patent: 4878188 (1991-10-01), Ziegler
patent: 5010576 (1991-04-01), Hill
patent: 5022082 (1991-06-01), Eriksson et al.
patent: 5063598 (1991-11-01), Geddes
patent: 5140640 (1992-08-01), Graupe et al.
patent: 5146505 (1992-09-01), Pfaff et al.
patent: 5170433 (1992-12-01), Elliott et al.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Active noise control system for attenuating engine generated noi 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 system for attenuating engine generated noi, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Active noise control system for attenuating engine generated noi will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-1255309

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.