US3603738A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Time-domain pitch detector and circuits for extracting a signal representative of pitch-pulse spacing regularity in a speech wave
Assignee: Lanteris Space LLC
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Filing: 1969-07-07
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Granted: 1971-09-07
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Expires: 1989-07-07
Abstract
Abstract A time-domain detector circuit for producing a signal representative of the pitch pulses of a speech wave. The circuit comprises two peak detectors having two different time constants to which the input speech wave is supplied. The output of the shorter-time-constant detector is supplied to an isolating stage (e.g., an emitter follower network). The output of the longertime-constant peak detector is connected, via a zener diode, to the output terminal of the emitter-follower network. A differentiator circuit is connected to the output terminal of the longer-time-constant detector. When the potential difference across the zener diode rises to a sufficiently high value, the zener-diode conducts, enabling the emitter follower network to load the longer-time-constant peak detector. The shorter-timeconstant peak detector detects the pitch pulses and supplies them to the output terminal of the longer-time-constant detector. When the amplitude level of the speech wave is relatively constant, the zener diode isolates the output of the shorter-time-constant detector from the output terminal of the other detector and only the long-time-constant detector supplies an output signal thereto. One circuit includes an input speech wave, a clipper, ramp generator, peak detector and low-pass filter connected in series. Another circuit includes pitch pulses, a pulse width-to-amplitude converter, a sample-and-hold circuit, a differentiator and a second sample-hold circuit connected in series with delayed pitch pulses timing each sample and hold circuit.
Inventors
- 👤 Louis R Focht
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:26
CPC Classifications
G; G10; G10L; G10L25/00; G10L25/90
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
75 words
In a circuit for extracting a signal representative of the pitch pulse spacing regularity of a speech wave, a signal representative of a speech wave, first means for generating a signal representative of the low frequency components of said signal when said signal is supplied to said first means, and second means coupled to said first means for generating a signal proportional to the peak voltage points of the output signal from said first means.
Claim 2
Dependent Claim
75 words
In a circuit for extracting a signal representative of the pitch pulse spacing regularity of a speech wave, a signal representative of a speech wave, first means for generating a signal representative of the low frequency components of said signal when said signal is supplied to said first means, and second means coupled to said first means for generating a signal proportional to the peak voltage points of the output signal from said first means.
Claim 3
Dependent Claim
33 words
The circuit of claim 1 in which said first means comprises a peak clipping network and a pulse length to pulse amplitude converter network and said second means is a peak detector network.
Claim 4
Dependent Claim
19 words
The circuit of claim 2 in which a low pass filter network is coupled to said peak detector network.
Claim 5
Dependent Claim
60 words
In a circuit for extracting a signal representative of the pitch pulse spacing regularity of a speech wave, a source of pitch pulses, a first sample and hold circuit coupled to said source, a differentiator network, a second sample and hold circuit, and means for coupling said differentiator network in cascade with said first and second sample and hold networks.
Claim 6
Dependent Claim
60 words
In a circuit for extracting a signal representative of the pitch pulse spacing regularity of a speech wave, a source of pitch pulses, a first sample and hold circuit coupled to said source, a differentiator network, a second sample and hold circuit, and means for coupling said differentiator network in cascade with said first and second sample and hold networks.
Claim 7
Dependent Claim
22 words
The circuit of claim 4 in which said sample and hold circuits sample the maximum amplitude points of their respective input signals.
Claim 8
Dependent Claim
175 words
In a circuit for producing a signal representative of the pitch pulses of a speech wave, a source of a signal representative of said speech wave, a first peak detector stage and a second peak detector stage, each of said stages having an input terminal and an output terminal, means for supplying said signal representative of said speech wave to said input terminal of each of said stages, an emitter follower network having an input terminal and an output terminal, means connecting said output terminal of said second peak detector stage to said input terminal of said emitter follower netwoRk, a voltage threshold conduction device, means connecting said device between said output terminal of said emitter follower network and said output terminal of said first peak detector stage, and means, coupled to said output terminal of said first peak detector stage, for preferentially transmitting the high frequency components of the signal produced by said circuit at said output terminal of said first peak detector stage in response to said signal representative of said speech wave.
Claim 9
Dependent Claim
175 words
In a circuit for producing a signal representative of the pitch pulses of a speech wave, a source of a signal representative of said speech wave, a first peak detector stage and a second peak detector stage, each of said stages having an input terminal and an output terminal, means for supplying said signal representative of said speech wave to said input terminal of each of said stages, an emitter follower network having an input terminal and an output terminal, means connecting said output terminal of said second peak detector stage to said input terminal of said emitter follower netwoRk, a voltage threshold conduction device, means connecting said device between said output terminal of said emitter follower network and said output terminal of said first peak detector stage, and means, coupled to said output terminal of said first peak detector stage, for preferentially transmitting the high frequency components of the signal produced by said circuit at said output terminal of said first peak detector stage in response to said signal representative of said speech wave.
Claim 10
Dependent Claim
62 words
The circuit of claim 6 in which said first peak detector stage has a longer time constant than said second peak detector stage and said voltage threshold conduction device is a zener diode poled to conduct when the potential difference between said output terminal of said first peak detector stage and said output terminal of said emitter-follower stage exceeds a given amount.
Claim 11
Dependent Claim
233 words
A circuit according to claim 7, wherein said first peak detector stage comprises a first transistor having an emitter, a collector and a base of given conductivity type, a first time-constant network comprising first resistive means and first capacitive means connected in parallel relationship, said first network having a given time constant, means including said first network for applying a first operating voltage to said emitter, and means for applying a second operating voltage to said collector, said second peak detector stage comprises a second transistor having an emitter, a collector and a base of said given conductivity type, a second time-constant network comprising second resistive means and second capacitive means connected in parallel relationship, said second network having a time constant shorter than said given time constant, means including said second network for applying said first operating voltage to said emitter of said second transistor, and means for applying said second operating voltage to said collector of said second transistor, said emitter-follower stage comprises a third transistor having an emitter, a collector and a base of said given conductivity type, means connecting said emitter of said second transistor to said base of said third transistor, and third resistive means for applying said first operating voltage to said emitter of said third transistor, and means connecting said zener diode between said emitter of said first transistor and said emitter of said third transistor.
Claim 12
Dependent Claim
45 words
A circuit according to claim 8, wherein each of said first, second and third transistors has an N-type base and said zener diode has its anode connected to said emitter of said first transistor and its cathode connected to said emitter of said third transistor.
References Cited (Backward Citations)
US3463885A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-06 | 1975-03-08 | 1975-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-06 | 1979-03-08 | 1979-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-06 | 1983-03-08 | 1983-09-07 | $7700.00 | Window Closed / Lapsed |