Patent
1980-09-16
1982-11-02
Kemeny, Emanuel S.
179 1VC, 179 1P, G10L 104
Patent
active
043574912
ABSTRACT:
Speech signal presence is decided based on the input signal exceeding either of two thresholds: one, a fixed threshold (TF) set at an arbitrary level relatively high above anticipated noise; the other, an adaptive threshold (TL) which idles slightly above noise. If the input signal rises above the idling threshold of TL, speech presence is indicated. If the input signal continues to rise (i.e., amplitude-time slope positive), the presence indication continues. If the input signal level falls, the adaptive threshold is adjusted (TL=BT+D, where for example B=1, D=5 and T=the current signal sample average value). Hangover is controlled by the amount of time the input signal exceeds the threshold TL. Speech presence is also indicated by the input signal exceeds a third threshold (TH) which is also adaptive, and idles at a relatively high level above noise.
REFERENCES:
patent: 3712959 (1973-01-01), Farriell
patent: 3832491 (1974-08-01), Sciulli et al.
patent: 3832493 (1974-08-01), Clark
patent: 3878337 (1975-04-01), Fariello
patent: 4008375 (1977-02-01), Lanier
patent: 4028496 (1977-06-01), LaMarche et al.
patent: 4052568 (1977-10-01), Jankowski
patent: 4057690 (1977-11-01), Vagliani et al.
patent: 4277645 (1981-07-01), May
Electronics (International), "Phone Setup Doubles Channel Capacity", Mar. 17, 1977, pp. 9E, 10E.
Daaboul Fouad
Le Van Tiu
Haley R. John
Kemeny Emanuel S.
Northern Telecom Limited
LandOfFree
Method of and apparatus for detecting speech in a voice channel does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of and apparatus for detecting speech in a voice channel , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of and apparatus for detecting speech in a voice channel will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-625184