05402496 is referenced by 179 patents and cites 6 patents.

A noise and feedback suppression apparatus processes an audio input signal having both a desired component and an undesired component. When implemented so as to effect noise cancellation, the apparatus includes a first filter operatively coupled to the input signal. The first filter generates a focused reference signal by selectively passing an audio spectrum of the input signal which primarily contains the undesired component. The reference signal is supplied to an adaptive filter disposed to filter the input signal so as to provide an adaptive filter output signal. A combining network subtracts the adaptive filter output signal from the input signal to create an error signal. The noise suppression apparatus further includes a second filter for selectively passing to the adaptive filter an audio spectrum of the error signal substantially encompassing the spectrum of the undesired component of the input signal. This cancellation effectively removes the undesired component from the input signal without substantially affecting the desired component of the input signal. When the present apparatus is implemented so as to suppress feedback the adaptive filter output signal is employed to cancel a feedback component from the input signal.

Title
Auditory prosthesis, noise suppression apparatus and feedback suppression apparatus having focused adaptive filtering
Application Number
7/912886
Publication Number
5402496
Application Date
July 13, 1992
Publication Date
March 28, 1995
Inventor
Gregory P Widin
West Lakeland Township, Washington County
MN, US
Kevin M Buckley
Robbinsdale
MN, US
Sigfrid D Soli
Sierra Madre
CA, US
Agent
William D Bauer
Walter N Kirn
Gary L Griswold
Assignee
Minnesota Mining and Manufacturing Company
MN, US
IPC
H03H 17/02
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