Electrical audio signal processing systems and devices – Noise or distortion suppression – Interpolation
Patent
1993-02-23
1995-07-11
Kuntz, Curtis
Electrical audio signal processing systems and devices
Noise or distortion suppression
Interpolation
381 37, 381 47, H04B 1500
Patent
active
054328594
ABSTRACT:
A noise-suppression circuit (10) divides the signal from a microphone (12) into a plurality of frequency sub-bands by means of a noise-band divider (18) and a subtraction circuit (36). By means of gain circuits (32) and (34), it applies separate gains to the separate bands and then recombines them in a signal combiner (38) to generate an output signal in which the noise has been suppressed. Separate gains are applied only to the lower subbands in the voice spectrum. Accordingly, the noise-band divider (18) is required to compute spectral components for only those bands. By employing a sliding-discrete-Fourier-transform method, the noise-band divider (18) computes the spectral components on a sample-by-sample basis, and circuitry (50, 52) for determining the individual gains can therefore update them on a sample-by-sample basis, too.
REFERENCES:
patent: 4628529 (1986-12-01), Borth et al.
patent: 4630304 (1986-12-01), Borth et al.
patent: 4630305 (1986-12-01), Borth et al.
patent: 4811404 (1989-03-01), Vilmur et al.
patent: 4837832 (1989-06-01), Fanshel
patent: 5012519 (1991-04-01), Adlersberg et al.
patent: 5023906 (1991-06-01), Novas
patent: 5133013 (1992-07-01), Munday
patent: 5251263 (1993-10-01), Andrea et al.
McAulay, Robert J., "Speech Enhancement Using a Soft-Decision Noise Suppression Filter," IEEE Transactions on Acoustics, Speech, and Signal Processing, vol. ASSP-28, No. 2, Apr. 1980.
Lim, Jae S. and Oppenheim, Alan V., "Enhancement and Bandwidth Compression of Noisy Speech," Proceedings of the IEEE, vol 67 No. 12, Dec. 1979.
Chan, Wai-Yip and Falconer, David D., "Speech Detection for a Voice/Data Mobile Radio Terminal", 1988 IEEE, pp. 1650-1654.
Narayan, S. Shankar; Peterson, Allen M.; Narasimha, Madihally, "Transform Domain LMS Algorithm," IEEE Transactions on Acoustics, Speech, and Signal Processing, vol. ASSP-31, No. 3 Jun. 1983.
Shynk, John J., "Frequency-Domain and Multirate Adaptive Filtering," IEEE SP Magazine, Jan. 1992.
Sendyk Andrew
Yang Jin
Kuntz Curtis
Lee Ping W.
NovAtel Communications Ltd.
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