US3723951A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acoustical detector circuit
Assignee: United States Department of the Navy
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Filing: 1963-06-05
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Granted: 1973-03-27
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Expires: 1983-06-05
Abstract
Abstract 2. An apparatus for use in underwater active-acoustic echoranging systems to provide a measure of the variable ratio of self-noise to reverberation signals during listening intervals between successive search-pulse transmission instants, said apparatus comprising, in combination: HYDROPHONE MEANS FOR RECEPTION OF TARGET-ECHO SIGNALS IN A BACKGROUND OF REVERBERATION AND SELF-NOISE SIGNALS; A LIMITER CIRCUIT FOR CONVERSION OF SAID SIGNALS TO A RECTANGULAR-WAVEFORM SIGNAL HAVING THE SAME ZERO-AXIS CROSSING CHARACTERISTICS AS THE SIGNAL RECEIVED BY SAID HYDROPHONE MEANS; MULTI-VIBRATOR MEANS ADAPTED TO PROVIDE, IN RESPONSE TO TRIGGERING ACTION OF SAID RECTANGULAR-WAVEFORM SIGNAL WHENEVER IT CHANGES POLARITY IN PRESELECTED SENSE, A TRAIN OF SHORT PULSES OF FIXED DURATION AND AMPLITUDE; SAID TRAIN OF PULSES PRESENTING A FREQUENCY-VARIATIONAL CHARACTERISTIC EVIDENCED BY AN A.C. ripple signal which in a predetermined frequency band is of magnitude increasing with self-noise/reverberation signal ratio; MEANS INCLUDING A BAND-PASS FILTER FOR PASSING ONLY SAID PREDETERMINED FREQUENCY BAND OF A.C. ripple signal; and MEANS RESPONSIVE TO SAID A.C. ripple signal in said predetermined frequency band to provide a measure of said selfnoise/reverberation signal ratio.
Inventors
- 👤 L Kush
- 👤 W Baker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 13:35
CPC Classifications
F; F41; F41G; F41G7/00; F41G7/20; F41G7/22; F41G7/2273; F41G7/228; G; G01; G01S; G01S7/00; G01S7/52; G01S7/523; G01S7/526; G01S7/527; Y; Y10; Y10S; Y10S367/00; Y10S367/901
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
171 words
In a marine torpedo adapted to receive acoustic signals from a target and to home upon these signals, the combination comprising: a hydrophone adapted to detect acoustic signals from an aquatic environment; a hard-limiter circuit connected to the output of said hydrophone to produce a pulse of changing polarity when the signal output from said hydrophone changes polarity; a blocking oscillator multi-vibrator circuit connected to the output of said limiter and adapted to produce a short pulse of fixed duration and energy when the signal from said limiter circuit changes polarity in preselected sense; a bandpass filter circuit connected to the output of said limiter circuit tuned to allow the passage of a discrete band of frequencies; an amplifier circuit connected to the output of said filter circuit; a rectifier circuit connected to the output of said amplifier circuit; a voltage measuring means connected to the output of said rectifier circuit whereby the quality of acoustical signal impinging upon said hydrophone can be determined by reference to said voltage measuring means.
Claim 2
Dependent Claim
171 words
In a marine torpedo adapted to receive acoustic signals from a target and to home upon these signals, the combination comprising: a hydrophone adapted to detect acoustic signals from an aquatic environment; a hard-limiter circuit connected to the output of said hydrophone to produce a pulse of changing polarity when the signal output from said hydrophone changes polarity; a blocking oscillator multi-vibrator circuit connected to the output of said limiter and adapted to produce a short pulse of fixed duration and energy when the signal from said limiter circuit changes polarity in preselected sense; a bandpass filter circuit connected to the output of said limiter circuit tuned to allow the passage of a discrete band of frequencies; an amplifier circuit connected to the output of said filter circuit; a rectifier circuit connected to the output of said amplifier circuit; a voltage measuring means connected to the output of said rectifier circuit whereby the quality of acoustical signal impinging upon said hydrophone can be determined by reference to said voltage measuring means.
Claim 3
Dependent Claim
171 words
In a marine torpedo adapted to receive acoustic signals from a target and to home upon these signals, the combination comprising: a hydrophone adapted to detect acoustic signals from an aquatic environment; a hard-limiter circuit connected to the output of said hydrophone to produce a pulse of changing polarity when the signal output from said hydrophone changes polarity; a blocking oscillator multi-vibrator circuit connected to the output of said limiter and adapted to produce a short pulse of fixed duration and energy when the signal from said limiter circuit changes polarity in preselected sense; a bandpass filter circuit connected to the output of said limiter circuit tuned to allow the passage of a discrete band of frequencies; an amplifier circuit connected to the output of said filter circuit; a rectifier circuit connected to the output of said amplifier circuit; a voltage measuring means connected to the output of said rectifier circuit whereby the quality of acoustical signal impinging upon said hydrophone can be determined by reference to said voltage measuring means.
Claim 4
Dependent Claim
171 words
In a marine torpedo adapted to receive acoustic signals from a target and to home upon these signals, the combination comprising: a hydrophone adapted to detect acoustic signals from an aquatic environment; a hard-limiter circuit connected to the output of said hydrophone to produce a pulse of changing polarity when the signal output from said hydrophone changes polarity; a blocking oscillator multi-vibrator circuit connected to the output of said limiter and adapted to produce a short pulse of fixed duration and energy when the signal from said limiter circuit changes polarity in preselected sense; a bandpass filter circuit connected to the output of said limiter circuit tuned to allow the passage of a discrete band of frequencies; an amplifier circuit connected to the output of said filter circuit; a rectifier circuit connected to the output of said amplifier circuit; a voltage measuring means connected to the output of said rectifier circuit whereby the quality of acoustical signal impinging upon said hydrophone can be determined by reference to said voltage measuring means.
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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) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |