US5459781A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Selectively activated dual tone multi-frequency detector
Assignee: Dialogic Corp Canada
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Filing: 1994-01-12
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Granted: 1995-10-17
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Expires: 2014-01-12
Abstract
Abstract A technique for improved DTMF detection utilizes a speech detector, either alone or in combination with other information from a voice processing arrangement, to adjust the sensitivity of the DTMF detector. The DTMF detector is turned completely off when the voice processing application is in the record mode, and when speech is detected.
Inventors
- 👤 Jeffrey I. Kaplan
- 👤 Nicholas Zwick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:56
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/64; H04M1/65; H04M1/652; H04M1/82; H04Q; H04Q1/00; H04Q1/18; H04Q1/30; H04Q1/44; H04Q1/444; H04Q1/46; H04M3/00; H04M3/42; H04M3/50; H04M3/53; H04M3/533
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
148 words
A voice processing system comprising: a plurality of voice processing components for recording and playing back audio messages; a speech detector, arranged to analyze a signal being received over a telephone line from a remote user, and to detect whether speech is present in the signal being received; a tone detector, arranged to analyze the signal being received over the telephone line from the remote user, and for informing said one or more voice processing components when the tone detector detects any one of a plurality of predetermined tones in the signal being received; and means responsive to said speech detector detecting speech in said signal being received for preventing said tone detector from informing said one or more voice processing components when the tone detector detects at least one of the plurality of predetermined tones and only if said voice processing system is recording the audio messages.
Claim 2
Dependent Claim
148 words
A voice processing system comprising: a plurality of voice processing components for recording and playing back audio messages; a speech detector, arranged to analyze a signal being received over a telephone line from a remote user, and to detect whether speech is present in the signal being received; a tone detector, arranged to analyze the signal being received over the telephone line from the remote user, and for informing said one or more voice processing components when the tone detector detects any one of a plurality of predetermined tones in the signal being received; and means responsive to said speech detector detecting speech in said signal being received for preventing said tone detector from informing said one or more voice processing components when the tone detector detects at least one of the plurality of predetermined tones and only if said voice processing system is recording the audio messages.
Claim 3
Dependent Claim
20 words
The voice processing system of claim 1 further comprising an echo canceler for cancelling echoes received from the telephone line.
Claim 4
Dependent Claim
15 words
The voice processing system of claim 2 wherein the plurality of tones are DTMF tones.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-10-16 | 1999-04-17 | 1999-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-10-16 | 2003-04-17 | 2003-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-10-16 | 2007-04-17 | 2007-10-17 | $7700.00 | Window Closed / Lapsed |