Method and apparatus for suppressing acoustic feedback in an aud

Details Method and apparatus for suppressing acoustic feedback in an aud Method and apparatus for suppressing acoustic feedback in an aud

1997-06-03

1999-06-08

Lee, Ping

Electrical audio signal processing systems and devices

Feedback suppression

381 83, 379410, H04B 1500

Patent

active

059109947

ABSTRACT:
A method (FIGS. 6-8) for detecting and attenuating N feedback frequencies in a digitized signal uses a tree structure containing a plurality of staged filters. In a step (602), an array of digital filters (FIG. 8) having N branches (40) is constructed. The array is arranged in a tree structure with each branch (40) having several stages (42, 44, and 46). Many of the N filters are used simultaneously in multiple different branches of the tree structure thus reducing the total number of filters required to detect all N feedback frequencies. Within each branch, N-1 of the N filters are notch filters, and each of the N- 1 notch filters attenuates the digitized signal at one of the N feedback frequencies. The remaining one filter in each of the N branches is a bandpass filter that passes the remaining of the N feedback frequency. Therefore, each branch of the tree passes a unique feedback frequency absent of all other N-1 feedback frequencies.

REFERENCES:
patent: 4079199 (1978-03-01), Patronis, Jr.
patent: 4091236 (1978-05-01), Chen
patent: 4965833 (1990-10-01), McGregor et al.
patent: 5245665 (1993-09-01), Lewis et al.
patent: 5442712 (1995-08-01), Kawamura et al.
Lane, John, et al., "An Adaptive IIR Phase Measurement Structure for Estimation of Multiple Sinusoids", Proc. of ICASSP'90, Albuquerque, NM, Apr. 3-6, 1990.

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