EP 0047589 A1 19820317 - Method and apparatus for detecting speech in a voice channel signal.
Title (en)
Method and apparatus for detecting speech in a voice channel signal.
Title (de)
Verfahren und Vorrichtung für die Anzeige von Sprachsignalen in einem Übertragungskanal.
Title (fr)
Procédé et dispositif de détection de la parole sur une voie téléphonique.
Publication
Application
Priority
CA 359968 A 19800909
Abstract (en)
In a digital speech detector, a first detector (601) produces an output signal if any sample of a voice channel signal has a magnitude (T) exceeding a fixed threshold (TF) above noise levels. A second detector (602) produces a second threshold (TL) which is adaptively adjusted to noise levels on the channel by being set to a level above the current sample magnitude (T) each time that this does not exceed the preceding sample's magnitude (TP). When the sample magnitude (T) rises above the second threshold (TL), and for each subsequent sample of successively increasing magnitude, the second detector (602) produces an output signal. A speech decision for the voice channel is reached if either detector (601, 602) produces its output signal. The output signals of the first and second detectors (601,602) are maintained for fixed and variable, respectively, hangover periods to maintain the speech decision during intersyllabic pauses in speech. The samples are supplied to the speech detector by an offset remover and averaging circuit.
IPC 1-7
IPC 8 full level
G10L 11/00 (2006.01); G10L 11/02 (2006.01); G10L 15/04 (2006.01); G10L 25/78 (2013.01); H04B 3/20 (2006.01); H04B 14/04 (2006.01); H04J 3/17 (2006.01)
CPC (source: EP)
G10L 25/78 (2013.01)
Citation (search report)
- US 3712959 A 19730123 - FARIELLO E
- US 4052568 A 19771004 - JANKOWSKI JOSEPH ALBIN
- Electronics International, Vol. 50, No. 6, March 17, 1977, New York, US "Phone Setup Doubles Channel Capacity with Digital Help", pages 9E, 10E * page 9E, right-hand column, lines 44-46 *
Designated contracting state (EPC)
DE FR GB IT NL SE
DOCDB simple family (publication)
EP 0047589 A1 19820317; EP 0047589 B1 19840613; CA 1147071 A 19830524; DE 3164171 D1 19840719; JP H0311139 B2 19910215; JP S5781733 A 19820521
DOCDB simple family (application)
EP 81303695 A 19810813; CA 359968 A 19800909; DE 3164171 T 19810813; JP 14044981 A 19810908