Systems and methods for adaptive noise cancellation including secondary path estimate monitoring
First Claim
1. A personal audio device comprising:
- a personal audio device housing;
a transducer coupled to the housing for reproducing an audio signal including both a source audio signal for playback to a listener and an anti-noise signal for countering the effects of ambient audio sounds in an acoustic output of the transducer;
a reference microphone coupled to the housing for providing a reference microphone signal indicative of the ambient audio sounds;
an error microphone coupled to the housing in proximity to the transducer for providing an error microphone signal indicative of the acoustic output of the transducer and the ambient audio sounds at the transducer; and
a processing circuit that implements;
an anti-noise generating filter having a response that generates at least a portion of the anti-noise signal;
a secondary path estimate filter configured to model an electro-acoustic path of the source audio signal and have a response that generates a secondary path estimate from the source audio signal; and
a secondary path estimate performance monitor for monitoring performance of the secondary path estimate filter in modeling the electro-acoustic path based on the error microphone signal and a playback correct error signal, wherein the playback corrected error is based on a difference between the error microphone signal and the secondary path estimate.
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Accused Products
Abstract
In accordance with methods and systems of the present disclosure, a processing circuit may implement at least one of: a feedback filter having a response that generates at least a portion of an anti-noise component from a playback corrected error, the playback corrected error based on a difference between the error microphone signal and a secondary path estimate; and a feedforward filter having a response that generates at least a portion of the anti-noise signal from a reference microphone signal. The processing circuit may also implement a secondary path estimate filter configured to model an electro-acoustic path of a source audio signal and have a response that generates a secondary path estimate from the source audio signal and a secondary path estimate performance monitor for monitoring performance of the secondary path estimate filter in modeling the electro-acoustic path.
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Citations
37 Claims
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1. A personal audio device comprising:
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a personal audio device housing; a transducer coupled to the housing for reproducing an audio signal including both a source audio signal for playback to a listener and an anti-noise signal for countering the effects of ambient audio sounds in an acoustic output of the transducer; a reference microphone coupled to the housing for providing a reference microphone signal indicative of the ambient audio sounds; an error microphone coupled to the housing in proximity to the transducer for providing an error microphone signal indicative of the acoustic output of the transducer and the ambient audio sounds at the transducer; and a processing circuit that implements; an anti-noise generating filter having a response that generates at least a portion of the anti-noise signal; a secondary path estimate filter configured to model an electro-acoustic path of the source audio signal and have a response that generates a secondary path estimate from the source audio signal; and a secondary path estimate performance monitor for monitoring performance of the secondary path estimate filter in modeling the electro-acoustic path based on the error microphone signal and a playback correct error signal, wherein the playback corrected error is based on a difference between the error microphone signal and the secondary path estimate. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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14. A method for canceling ambient audio sounds in the proximity of a transducer of a personal audio device, the method comprising:
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receiving a reference microphone signal indicative of the ambient audio sounds; receiving an error microphone signal indicative of the output of the transducer and the ambient audio sounds at the transducer; generating a source audio signal for playback to a listener; generating an anti-noise signal for countering the effects of ambient audio sounds at an acoustic output of the transducer; generating a secondary path estimate from the source audio signal by filtering the source audio signal with a secondary path estimate filter modeling an electro-acoustic path of the source audio signal; monitoring with a secondary path estimate performance monitor performance of the secondary path estimate filter in modeling the electro-acoustic path based on the error microphone signal and a playback correct error signal, wherein the playback corrected error is based on a difference between the error microphone signal and the secondary path estimate; and combining the anti-noise signal with a source audio signal to generate an audio signal provided to the transducer. - View Dependent Claims (15, 16, 17, 18, 19, 20, 21, 22, 23, 24)
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25. An integrated circuit for implementing at least a portion of a personal audio device, comprising:
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an output for providing a signal to a transducer including both a source audio signal for playback to a listener and an anti-noise signal for countering the effect of ambient audio sounds in an acoustic output of the transducer; a reference microphone input for receiving a reference microphone signal indicative of the ambient audio sounds; an error microphone input for receiving an error microphone signal indicative of the output of the transducer and the ambient audio sounds at the transducer; and a processing circuit that implements; an anti-noise generating filter having a response that generates at least a portion of the anti-noise signal; a secondary path estimate filter configured to model an electro-acoustic path of the source audio signal and have a response that generates a secondary path estimate from the source audio signal; and a secondary path estimate performance monitor for monitoring performance of the secondary path estimate filter in modeling the electro-acoustic path based on the error microphone signal and a playback correct error signal, wherein the playback corrected error is based on a difference between the error microphone signal and the secondary path estimate. - View Dependent Claims (26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37)
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Specification