Patent classifications
G10K11/17833
Automatic noise cancellation using multiple microphones
The disclosure includes a headset comprising one or more earphones including one or more sensing components. The headset also includes one or more voice microphones to record a voice signal for voice transmission. The headset also includes a signal processor coupled to the earphones and the voice microphones. The signal processor is configured to employ the sensing components to determine a wearing position of the headset. The signal processor then selects a signal model for noise cancellation. The signal model is selected from a plurality of signal models based on the determined wearing position. The signal processor also applies the selected signal model to mitigate noise from the voice signal prior to voice transmission.
Active transit vehicle classification
A method performed by a wearable audio output device worn by a user is provided for controlling the reproduction of external noise and/or noise masking. A first a first lower-power detector determines if the user is in transport or a change in the user's transport. In response to the determination, a second higher-power detector exits a power saving state and determines a mode of the transport based. The wearable audio output device adjust a level of attenuation applied by the wearable audio output device to the external noise or adjusting a level of noise masking output by the wearable audio output device based on the determined mode of the transport.
Audio processing system
An audio processing system is described including an amplifier configured to receive a first audio signal and output the first audio signal to an acoustic transducer comprising a voice coil. A sensor detects a signal corresponding to voice coil current of the acoustic transducer. A controller compares the first audio signal and the detected signal and determines a second audio signal from the comparison. The second audio signal is representative of an external sound source detected via the acoustic transducer. The audio processing system may simultaneously output the first audio signal and receive the second audio signal using the same acoustic transducer.
In-vehicle noise cancellation adaptive filter divergence control
A active noise cancellation (ANC) system may include an adaptive filter divergence detector for detecting divergence of the one or more controllable filters as they adapt, based on various temporal or frequency domain amplitude characteristics. Upon detection of a controllable filter divergence, the ANC system may be deactivated, or certain speakers may be muted. Alternatively, the ANC system may modify the diverged controllable filters to restore proper operation of the noise cancelling system. This may include adjusting a leakage value of an adaptive filter controller.
Real-time detection of feedforward instability
Audio devices and methods are provided for detecting instability in an associated feedforward audio processing system. A microphone provides a feedforward signal for processing by a feedforward filter. The processed signal may provide noise reduction and/or sound enhancement associated with the surrounding environment. The processed signal contributes to a driver signal provided to an acoustic transducer, e.g., a driver, to produce acoustic signals for a user. A processor is configured to detect an indication of instability in one or more of the signals, and to adjust a phase response of the feedforward signal path in response to detecting the indication of instability.
Instability Mitigation in an Active Noise Reduction (ANR) System Having a Hear-Through Mode
In one aspect a method that includes receiving an input signal captured by one or more first sensors associated with an active noise reduction (ANR) device, and processing the input signal using a first filter disposed in an ANR signal path to generate a first signal for an acoustic transducer of the ANR device. The input signal is processed in a pass-through signal path disposed in parallel with the ANR signal path to generate a second signal for the acoustic transducer, wherein the pass-through signal path allows a portion of the input signal to pass through to the acoustic transducer in accordance with a variable gain. One or more second sensors detect an existence of a condition likely to cause instability in the pass-through signal path, and in response, the variable gain is adjusted. A driver signal for the acoustic transducer is generated using an output based on the adjusted gain.
Gain Adjustment in ANR System with Multiple Feedforward Microphones
Technology described in this document can be embodied in a method that includes receiving a first input signal representing audio captured by a first sensor disposed in a signal path of an active noise reduction (ANR) device, and receiving a second input signal representing audio captured by a second sensor disposed in the signal path of the ANR device. The method also includes processing, by at least one compensator, the first input signal and the second input signal to generate a drive signal for an acoustic transducer of the ANR device. A gain applied to the signal path is at least 3 dB less relative to an ANR signal path having a single sensor.
ACTIVE NOISE CONTROL METHOD AND SYSTEM
A method for reducing the power of an acoustic primary noise signal (d.sub.m(n)) at one or more control positions in a vehicle passenger compartment using an adaptive filter. The method comprising to compare a mean correlation coefficient (.sub.m(n)) between an electrical error signal (e.sub.m(n) and a modelled secondary anti-noise signal .sub.m(n) with at least one predefined threshold (, ).
HEADSET SYSTEM FAILURE DETECTION
A headset system comprises: a headset comprising at least one microphone and at least one speaker and configured to transmit and receive sound; a wire system coupled to the headset and comprising a wire; and a control unit coupled to the wire system and configured to: receive from the wire a combined signal comprising a first signal and a second signal, determine that the first signal is a spurious signal, and detect a failure of the wire system based on the determining.
IN-VEHICLE NOISE CANCELLATION ADAPTIVE FILTER DIVERGENCE CONTROL
A active noise cancellation (ANC) system may include an adaptive filter divergence detector for detecting divergence of the one or more controllable filters as they adapt, based on various temporal or frequency domain amplitude characteristics. Upon detection of a controllable filter divergence, the ANC system may be deactivated, or certain speakers may be muted. Alternatively, the ANC system may modify the diverged controllable filters to restore proper operation of the noise cancelling system. This may include adjusting a leakage value of an adaptive filter controller.