Methods for calibrating active noise-cancelling headphones, including placing the active noise-cancelling headphones on a measuring device; exciting the active noise-cancelling filter; measuring one or more relevant transmission pathways selected from x(n), m(n), and p(n) for feedforward and/or h(n) for feedback; defining at least one goal function for feedforward or feedback; calculating a complementary function for the defined goal function for at least one branch of the active noise-cancelling filter; calculating an impulse response of the complementary function from the measurements of the relevant transmission pathways; approximating operating parameters for the active noise-cancelling filter using the Prony method; and implementing the approximated operating parameters in the active noise-cancelling filter on the signal processor in order to create an approximated complementary active noise-cancelling filter, thereby calibrating the active noise-cancelling headphones.

Adaptive filters output a cancellation sound from a speaker, a selector selects outputs of a plurality of auxiliary filters each corresponding to different positions, a subtractor subtracts the selected output from the output of the microphone and outputs the subtracted output to the adaptive filter as an error signal, and a position detection device detects a position of a head of a user. A transfer function estimated so that the error signal becomes 0 when noise is canceled at the corresponding position is preset in the auxiliary filter. When the auxiliary filter corresponding to the position close to the head of the user changes, the switching control unit stepwise increases the frequency with which the output of the auxiliary filter is selected by the selector to 100%.

In-car communication and hands-free talking with good sound quality are realized. An echo cancelation apparatus (4) is for use in a vehicle in which microphones (M1, M2) and loudspeakers (S1, S2) are disposed in acoustic regions (100, 200). A loudspeaker (S1) and a microphone (M1) are disposed in a first acoustic region (100), and a loudspeaker (S2) and a microphone (M2) are disposed in a second acoustic region (200). An acoustic signal picked up by the microphone (M1) disposed in the first acoustic region (100) is emitted from the loudspeaker (S2) disposed in the second acoustic region (200). An acoustic signal picked up by the microphone (M2) disposed in the second acoustic region (200) is emitted from the loudspeaker (S1) disposed in the first acoustic region (100). The microphone (M1) is designed to hardly collect a sound emitted from the loudspeaker (S2).

A road noise cancellation (RNC) system is provided with at least one loudspeaker to project anti-noise sound within a passenger cabin of a vehicle in response to an anti-noise signal; and a controller. The controller is programmed to: determine a coherence value between a noise signal indicative of road induced noise and an error signal indicative of noise and the anti-noise sound within the passenger cabin; estimate a noise reduction value based on the coherence value; filter the noise signal and the error signal based on the estimated noise reduction value; and generate the anti-noise signal based on the filtered noise signal and the filtered error signal.

A system for reducing noise for a user includes a first detector configured to generate a first noise signal, wherein the first noise signal is a representation of a first noise that is transmitted to the user through a first sound pathway, and a second detector configured to generate a second noise signal, wherein the second noise signal indicates a second noise perceived by the user. The system also includes a processor configured to determine a noise correction signal based on the first noise signal and/or the second noise signal, and a speaker configured to generate a sound for reducing the noise based on the noise correction signal.

A simulation test system and method for vehicle road noise cancellation (RNC) are provided in one or more embodiments of the present disclosure. The simulation test system may include a vehicle RNC simulation system and a power amplifier. The vehicle RNC simulation system is configured to simulate an RNC system in a vehicle environment. The power amplifier is configured to execute an RNC algorithm and may perform data communication with the vehicle RNC simulation system. The vehicle RNC simulation system transmits acceleration data representing an acceleration signal and microphone data representing a microphone signal to the power amplifier as inputs to the RNC algorithm in the power amplifier. Moreover, the vehicle RNC simulation system may receive speaker data representing a speaker signal from the power amplifier. The vehicle RNC simulation system includes a secondary path simulation model and a signal flow simulation model.

A noise reduction system includes sensors configured to generate an input signal, an adaptive filter configured to represent a transfer function of a path traversed by the input signal, one or more processing devices, and one or more transducers. The processing devices receive the input signal and generate an updated set of filter coefficients of the adaptive filter by separating the input signal into frequency subbands; determining for each subband, coefficients of a corresponding subband adaptive module; and combining the coefficients of multiple subband adaptive modules. Determining the coefficients of the corresponding subband adaptive module includes selecting a subset of a precomputed set of filter coefficients of the adaptive filter. The processing devices process a portion of the input signal using the updated set of filter coefficients of the adaptive filter to generate an output that destructively interferes with another signal traversing the path represented by the transfer function.

Embodiments of this application disclose a noise cancellation apparatus and method. The noise cancellation apparatus includes a main control unit and a noise cancellation processing circuit. The main control unit determines a noise cancellation parameter based on a noise cancellation level index or a feature value for determining a matching degree between a headset and an ear canal of a user. The noise cancellation processing unit obtains an inverse phase noise of an ambient noise based on the noise cancellation parameter. After the inverse phase noise is mixed with a played downlink audio signal, the ambient noise can be canceled. In addition, because the noise cancellation parameter is determined from a preset noise cancellation parameter library based on the received or autonomously determined noise cancellation level index, instead of being uniformly configured, a noise cancellation level can be flexibly adjusted, thereby improving a noise cancellation effect and user experience.

A system and method for integrating a home media system and other home systems. As a non-limiting example, various aspects of this disclosure provide a system and method that flexibly and efficiently provide communication and/or resource sharing between a home media system and various other home systems.

A system and method for integrating a home media system and other home systems. As a non-limiting example, various aspects of this disclosure provide a system and method that flexibly and efficiently provide communication and/or resource sharing between a home media system and various other home systems.