发明名称 |
Feedback detector and suppressor |
摘要 |
An A/D converter converts an analog signal to a digital signal. A plurality of cascade-connected notch filters include a first notch filter which is connected to the output of the A/D converter. A D/A converter is connected to the output of the last stage notch filter for converting a digital signal to an analog signal. The output of the last stage notch filter is connected to the input of a fast Fourier transform unit for analyzing the frequency. Analysis results of the fast Fourier transform unit are supplied to a detector. A coefficient having the same center frequency as that of a peak frequency outputted from the detector is selected from a coefficient memory and it is transferred to a second coefficient memory. Thus, the frequencies of the notch filters are set to eliminate howling.
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申请公布号 |
US5677987(A) |
申请公布日期 |
1997.10.14 |
申请号 |
US19940276617 |
申请日期 |
1994.07.18 |
申请人 |
MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD. |
发明人 |
SEKI, NOBUYUKI;ONIZUKA, KAZUHIRO;KAWAMURA, AKIHISA |
分类号 |
H04B3/20;H04R3/02;(IPC1-7):G10L3/02;G10L9/00;H04R27/00;H04B15/00 |
主分类号 |
H04B3/20 |
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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