Systems and methods for adaptive noise cancellation
AssigneeBBN Technologies Corp.
InventorsJohn C. Heine, Istvan L. Ver, William B. Coney, Robert D. Preuss
Life of this patent
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Abstract
A system (400) for reducing non-acoustic noise includes a primary sensor (420), at least one secondary sensor (410), a filter (415), and a summation unit (425). The primary sensor (420) measures pressure and produces a primary pressure signal. The at least one secondary sensor (410) measures pressure and produce a secondary pressure signal. The filter (415) processes the secondary pressure signal to produce a filtered pressure signal. The summation unit (425) subtracts the filtered pressure signal from the primary pressure signal to reduce non-acoustic noise in the primary pressure signal.
Claims21
A method, comprising:
- disposing a plurality of secondary sensors on an exterior surface of a three dimensional windscreen;
- disposing a primary sensor within an interior of the three dimensional windscreen;
- measuring pressure at the primary sensor to produce a primary pressure signal;
- measuring pressure at the plurality of secondary sensors to produce secondary pressure signals;
- filtering the secondary pressure signals to produce a filtered pressure signal;
- and
- subtracting the filtered pressure signal from the primary pressure signal to reduce noise, induced by non-acoustic pressure disturbances, in the primary pressure signal.
A system, comprising:
- a three dimensional windscreen having an exterior surface and an interior;
- a primary sensor located within the interior of the windscreen and configured to measure pressure and to produce a primary pressure signal;
- a plurality of secondary sensors disposed on the exterior surface of the windscreen and configured to measure pressure and to produce secondary pressure signals;
- a filter configured to process the secondary pressure signals to produce a filtered pressure signal;
- and
- a summation unit configured to subtract the filtered pressure signal from the primary pressure signal to reduce noise, induced by non-acoustic pressure disturbances, in the primary pressure signal.
A method, comprising:
- disposing a plurality of second sensors on an exterior surface of a three dimensional windscreen;
- disposing a first sensor within an interior of the three dimensional windscreen;
- sensing disturbances at the first sensor and the plurality of second sensors, the first sensor producing a first signal and the plurality of second sensors producing second signals;
- adaptively filtering the second signals to produce a filtered signal;
- and
- subtracting the filtered signal from the first signal to cancel the disturbances associated with the first signal.
A system for canceling disturbances from a sensor signal, comprising:
- a first sensor and a plurality of second sensors configured to sense disturbances, the first sensor producing a first signal and the plurality of second sensors producing second signals;
- a filter configured to adaptively filter the second signals to produce a filtered signal;
- a summation unit configured to subtract the filtered signal from the first signal to cancel the disturbances from the first signal;
- and a windscreen, wherein the first sensor is disposed within an interior of the windscreen and wherein the plurality of second sensors are disposed on an external surface of the windscreen.
A method, comprising:
- measuring pressure with a first sensor located inside a windscreen to produce a measurement signal;
- measuring pressure at a plurality of second sensors disposed on an exterior surface of the windscreen to infer a net pressure acting on the windscreen, the net pressure comprising acoustic and non-acoustic pressure;
- filtering signals from the plurality of second sensors to estimate a component of the non-acoustic pressure that is correlated with the net pressure;
- and
- subtracting the estimated component of non-acoustic pressure from the measurement signal to reduce noise in the measurement signal.
Dependencies are inferred from the claim text.