发明名称 |
NOISE CANCELLATION SYSTEM WITH GAIN CONTROL BASED ON NOISE LEVEL |
摘要 |
<p>A noise cancellation system is provided, for generating a noise cancellation signal to be added to a wanted signal to mitigate the effects of ambient noise. The system comprises: an input, for receiving an input signal representing ambient noise; a detector, for detecting a magnitude of said input signal; and a voice activity detector, for determining voiceless periods when said input signal does not contain a signal representing a voice. The detector is adapted to detect the magnitude of said input signal during said voiceless periods, and the system is adapted to operate in a first mode when said input signal is above a threshold value, and a second mode when said input signal is below the threshold value. The first mode comprises generating a noise cancellation signal with a first magnitude for at least partially cancelling the ambient noise. The second mode comprises generating a noise cancellation signal with a second magnitude that is less than the first magnitude.</p> |
申请公布号 |
WO2009081185(A1) |
申请公布日期 |
2009.07.02 |
申请号 |
WO2008GB51177 |
申请日期 |
2008.12.11 |
申请人 |
WOLFSON MICROELECTRONICS PLC;SIBBALD, ALASTAIR;ALCOCK, ROBERT DAVID |
发明人 |
SIBBALD, ALASTAIR;ALCOCK, ROBERT DAVID |
分类号 |
G10K11/178 |
主分类号 |
G10K11/178 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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