Noise separation hybrid active noise cancellation system
AssigneeSteadybeat Technology Corp.
InventorHao-Ming Chen
Life of this patent
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Abstract
The present invention provides an improved noise separation hybrid type ANC system, which includes a reference audio receiving device, an error audio receiving device, an audio output device, and an audio processing device. The audio processing device includes a feed-forward noise cancellation filter module, a feedback noise cancellation filter module, a mixer, a noise shaper, a first infinite impulse response filter, and a second infinite impulse response filter. When the noise bandwidth detector detects irregular noise, it adjusts the coefficient of the first infinite impulse response filter to set it as a low-pass filter; when regular noise is detected, the coefficient of the second infinite impulse response filter is adjusted to set it as a band-pass filter.
Claims16
An improved noise separation hybrid active noise cancellation system, comprising:
- a reference audio receiving device, receiving a reference audio source and outputting a reference audio source signal based on the reference audio source;
- an error audio receiving device, receiving an error audio source and outputting an error audio source signal based on the error audio source;
- an audio output device, outputting an audio signal;
- and
- an audio processing device, connected to the reference audio receiving device, the error audio receiving device and the audio output device;
- the audio processing device comprising a feed-forward noise cancellation filter module, a feedback noise cancellation filter module, a mixer, a noise shaper, a first infinite impulse response filter and a second infinite impulse response filter;
- the feed-forward noise cancellation filter module used for performing feed-forward noise cancellation on the reference audio signal received from the reference audio receiving device in order to obtain a feed-forward noise cancellation signal;
- the feedback noise cancellation filter module used for performing feedback noise cancellation on the error audio source signal received from the error audio receiving device in order to obtain a feedback noise cancellation signal;
- and transmitting the feed-forward noise cancellation signal and the feedback noise cancellation signal to the mixer to perform wave mixing, and outputting a noise cancellation signal after mixing to the audio output device;
- and
- wherein the noise shaper detects a noise bandwidth distribution of the error audio source signal, such that when the noise shaper detects an irregular noise, a coefficient of the first infinite impulse response filter is adjusted to set the first infinite impulse response filter as a low-pass filter, and the first infinite impulse response filter with the corrected coefficient converts the error audio source signal into a low frequency audio source correction signal for outputting to a feed-forward least mean square filter of the feed-forward noise cancellation filter module;
- when the noise shaper detects a regular noise, a coefficient of the second infinite impulse response filter is adjusted to set the second infinite impulse response filter as a band-pass filter, and the second infinite impulse response filter with the corrected coefficient converts the error audio source signal into a designated bandwidth audio source correction signal for outputting to a feedback least mean square filter of the feedback noise cancellation filter module.
Dependencies are inferred from the claim text.