Electrical audio signal processing systems and devices – Noise or distortion suppression – Interpolation
Patent
1992-03-31
1994-02-08
Isen, Forester W.
Electrical audio signal processing systems and devices
Noise or distortion suppression
Interpolation
H04B 1500
Patent
active
052855023
ABSTRACT:
A signal processing circuit is incorporated into an audio reproducing device for suppressing noise while preserving distinctive features of speech. A noise detecting circuit includes a low pass filtering circuit (12) and a level detector (14). An output signal (C) from the detecting circuit controls a variable high pass filtering circuit (20) to attenuate a range of low frequencies of an input signal (A) proportional to the detected level of noise. The variable high pass filtering circuit exhibits a family of variable response curves (22, 24, and 26) that vary in slope below a common cut-off frequency (28) that is below a range of frequencies that convey a majority of second formant transitions between consonants and vowels.
REFERENCES:
patent: 3209083 (1965-09-01), Posen
patent: 3764745 (1973-10-01), Bottcher et al.
patent: 3792367 (1974-02-01), Fleischer et al.
patent: 3920931 (1975-11-01), Yanick, Jr.
patent: 3927279 (1975-12-01), Nakamura et al.
patent: 4025721 (1977-05-01), Graupe et al.
patent: 4061875 (1977-12-01), Freifeld et al.
patent: 4119814 (1978-10-01), Harless
patent: 4405831 (1983-09-01), Michelson
patent: 4490585 (1984-12-01), Tanaka
patent: 4718099 (1988-01-01), Hotvet
patent: 4750207 (1988-06-01), Gebert et al.
patent: 4792977 (1988-12-01), Anderson et al.
patent: 4837832 (1989-06-01), Fanshel
patent: 5001441 (1991-03-01), Gen-Kuong
"Designing with the Adaptive High Pass Filter", Gennum Corporation, Oct. 1989.
"Sound Field Audiometry and Hearing Aid Selection", pp. 204-207, Hearing Instrument Selection and Evaluation, Ernest Zelnick, Editor, published by Natl. Institute for Hearing Instruments Studies, 1987.
"Review of Suggested Hearing Aid Procedures," pp. 20-25, Ibid.
"Hearing Aid Assessment and Use in Audiologic Habilitation", Wm. R. Hodgson, Ed., publ. by Wms. & Wilkins., Chapters 5 (pp. 109-125) & 6 (pp. 128-144), 1981.
"Active Filter Design Using Operational Transconductance Amplifiers: A Tutorial", by. R. A. Geiger & E. Sanchez-Sinencio, pp. 20-32, IEEE Circuits and Devices, Mar. 1985.
Frisina Robert D.
Fuller Lynn F.
Miller Kenneth R.
Taylor James C.
Walton Joseph P.
Auditory System Technologies, Inc.
Isen Forester W.
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