EP 1121786 A4 20070530 - FAST DTMF IDENTIFICATION
Title (en)
FAST DTMF IDENTIFICATION
Title (de)
SCHNELLE DTMF-IDENTIFIZIERUNG
Title (fr)
IDENTIFICATION DE DTMF RAPIDE
Publication
Application
Priority
- US 9918401 W 19990813
- US 37420399 A 19990812
Abstract (en)
[origin: WO0113586A1] A method of detecting control tones in a digital signal by using a tone detection unit (11) (TDU) and a packet voice protocol unit (12) (PVPU) in a network over which the signal is transmitted. The TDU (11) detects the presence of a control tone in the signal within the first 5 ms of transmission and generates an alert signal (23) to the PVPU (12) to cease further transmission of the signal. Upon confirmation, the PVPU (12) may halt the transmission and buffer or delete the voice signal packets. Alternatively, if the control tones are not present in the signal, the PVPU (12) may continue transmission of any buffered packets. The method further incorporates the sending of the control tone signal to the receiving end of the transmission of the voice packets following transmission of the control tone to the receiving end.
IPC 8 full level
H04L 12/54 (2006.01); H04M 3/00 (2006.01); G05B 23/02 (2006.01); H04J 3/12 (2006.01); H04L 12/64 (2006.01); H04L 27/32 (2006.01); H04M 7/00 (2006.01); H04M 7/06 (2006.01); H04Q 1/30 (2006.01); H04Q 1/45 (2006.01)
CPC (source: EP)
H04L 12/6418 (2013.01); H04L 27/32 (2013.01); H04M 7/1295 (2013.01); H04L 2012/6475 (2013.01)
Citation (search report)
- [X] US 5666357 A 19970909 - JANGI SHRIRANG [US]
- See references of WO 0113586A1
Designated contracting state (EPC)
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE
Designated extension state (EPC)
AL LT LV MK RO SI
DOCDB simple family (publication)
WO 0113586 A1 20010222; AU 5482499 A 20010313; EP 1121786 A1 20010808; EP 1121786 A4 20070530; JP 2003507933 A 20030225
DOCDB simple family (application)
US 9918401 W 19990813; AU 5482499 A 19990813; EP 99941106 A 19990813; JP 2001517758 A 19990813