US4223180A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Human speech envelope tracker
Assignee: United States Department of the Army
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Filing: 1978-12-22
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Granted: 1980-09-16
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Expires: 1998-12-22
Abstract
Abstract This invention recovers the time waveform envelope of a human voice signalithout the loss of subtleties providing speaker recognition cues and voice quality. This is accomplished by rectifying the voice envelope and then obtaining slope information about the original time waveform to detect peaks which are successively held by sample and hold circuitry.
Inventors
- 👤 Thomas L. Eckels
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:27
CPC Classifications
G; G10; G10L; G10L17/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
64 words
A method of accurate human speech envelope recovery comprising: amplifying an audio signal of said human speech, rectifying said amplified audio signal to derive a series of peak values of said audio signal, differentiating said rectified audio signal to obtain slope information about each of said peak values, and sampling and holding the rectified audio signal for an interval determined by said differentiated signal.
Claim 2
Independent Claim
64 words
A method of accurate human speech envelope recovery comprising: amplifying an audio signal of said human speech, rectifying said amplified audio signal to derive a series of peak values of said audio signal, differentiating said rectified audio signal to obtain slope information about each of said peak values, and sampling and holding the rectified audio signal for an interval determined by said differentiated signal.
Claim 3
Dependent Claim
33 words
The method of claim 1, wherein the differentiating is such that a slight negative slope after any peak of said rectified signal is sufficient to cause that peak to be sampled and stored.
Claim 4
Dependent Claim
195 words
A human speech envelope tracker comprising: an audio signal representative of human speech, a preamplifier means having an input and an output for preamplifying said audio signal, a rectifier means having an input and an output for rectifying the output of said preamplifier, a differentiator means having an input and an output for differentiating the output of said rectifier means, an amplifier-limiter means having an input and an output for amplifying and limiting the output of said differentiator means, a pulse shaped means having an input and an output for shaping the output of said amplifier-limiter means, a pulse generator means having an input and an output for generating a pulse upon receipt of the output of said pulse shaper means, a sample and hold means having a first and second input and one output for sampling and holding the output of said rectifier means received at the first input means and outputing said rectifier means output upon receipt of the output of said pulse generator means at said second input, and a follower means having an input and an output for receiving the output of said sample and hold means and providing an output.
Claim 5
Dependent Claim
195 words
A human speech envelope tracker comprising: an audio signal representative of human speech, a preamplifier means having an input and an output for preamplifying said audio signal, a rectifier means having an input and an output for rectifying the output of said preamplifier, a differentiator means having an input and an output for differentiating the output of said rectifier means, an amplifier-limiter means having an input and an output for amplifying and limiting the output of said differentiator means, a pulse shaped means having an input and an output for shaping the output of said amplifier-limiter means, a pulse generator means having an input and an output for generating a pulse upon receipt of the output of said pulse shaper means, a sample and hold means having a first and second input and one output for sampling and holding the output of said rectifier means received at the first input means and outputing said rectifier means output upon receipt of the output of said pulse generator means at said second input, and a follower means having an input and an output for receiving the output of said sample and hold means and providing an output.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-09-16 | 1984-03-17 | 1984-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-16 | 1988-03-17 | 1988-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-16 | 1992-03-17 | 1992-09-16 | $7700.00 | Window Closed / Lapsed |