Jeffrey Alderson,Jon D. Hendrix,Gautham Devendra Kamath
申请号：
US13794979
公开号：
US09369798B1
申请日:
2013.03.12
申请国别(地区):
US
年份:
2016
代理人:
摘要：
A personal audio device, such as a headphone, includes an adaptive noise canceling (ANC) circuit that adaptively generates an anti-noise signal using one or more microphone signals that measure the ambient audio. The anti-noise signal is combined with source audio to provide an output for a speaker. The anti-noise signal causes cancellation of ambient audio sounds that appear in the microphone signals. A processing circuit uses the reference microphone to generate the anti-noise signal using one or more adaptive filters. The processing circuit also includes low-pass filters that remove quantization noise images at the output of the adaptive filter to reduce the dynamic range required at the output of the adaptive filter.
