Adaptation enhancement for a road noise cancellation system
AssigneeHarman International Industries, Incorporated
InventorKevin J. Bastyr
Life of this patent
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Abstract
A road noise cancellation (RNC) system may include a signal analysis controller for detecting non-stationary, transient events based on sensor signals having a spectral or temporal character significantly different from steady-state road or cabin noise. Upon detection of such non-stationary events, the RNC system may modify the sensor signals to mask the non-stationary event, thereby preventing the RNC system's adaptive filters from mis-adapting because of transient, non-stationary events. Alternatively, the RNC system may pause or slow or pause adaptation of its controllable filters for the duration of a frame that includes the non-stationary event.
Claims20
A method for preventing mis-adaptation in a feed-forward road noise cancellation (RNC) system, the method comprising:
- adjusting an adaptive transfer characteristic of a controllable filter based on a noise signal received from a vibration sensor, an error signal received from a microphone located in a cabin of a vehicle, and an adaptation parameter;
- generating an anti-noise signal based in part on the adaptive transfer characteristic, the anti-noise signal to be radiated by a speaker as anti-noise within the cabin of the vehicle;
- detecting a non-stationary event based on signal parameters sampled from a frame of the noise signal;
- and
- modifying the noise signal, in response to detecting the non-stationary event, to obtain an adjusted noise signal, wherein the adaptive transfer characteristic of the controllable filter is adjusted based in part on the adjusted noise signal.
A road noise cancellation (RNC) system comprising:
- a vibration sensor adapted to generate a noise signal on at least one output channel in response to an input;
- a controllable filter adapted to generate an anti-noise signal based in part on an adaptive transfer characteristic, the anti-noise signal to be radiated by a speaker as anti-noise within a cabin of a vehicle;
- an adaptive filter controller, including a processor and memory, programmed to control the adaptive transfer characteristic of the controllable filter based on the noise signal received from the vibration sensor, an error signal received from a microphone located in the cabin of the vehicle, and an adaptation parameter;
- and
- a signal analysis controller, including a processor and memory, programmed to:
- detect a non-stationary event based on parameters sampled front a current frame of the error signal;
- and
- modify the error signal, in response to detecting the non-stationary event, to obtain an adjusted error signal, wherein the adaptive transfer characteristic of the controllable filter is controlled based in part on the adjusted error signal.
A computer-program product embodied in a non-transitory computer readable medium that is programmed for road noise cancellation (RNC), the computer-program product comprising instructions for:
- receiving noise signals from at least one vibration sensor;
- detecting a non-stationary event based on signal parameters sampled from a frame of at least one noise signal;
- modifying the at least one noise signal for a duration of the frame to obtain at least one adjusted noise signal in response to detecting the non-stationary event;
- and
- generating an anti-noise signal to be radiated by a speaker as anti-noise within a cabin of a vehicle based on the adjusted noise signal.
Dependencies are inferred from the claim text.