US3891960A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Doppler sonar system
Assignee: United States Department of the Navy
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Filing: 1970-02-24
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Granted: 1975-06-24
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Expires: 1990-02-24
Abstract
Abstract A system of acoustic echo ranging for the measurement of bearing and range to an underwater object which is in motion toward or away from the detection system located at a selected position. A signal design which results in a very high ability to select only the moving objects and reject any signals which return from the surface or bottom of an ocean, river, or lake.
Inventors
- 👤 Maurice W Widener
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:33
CPC Classifications
G; G01; G01S; G01S15/00; G01S15/02; G01S15/50; G01S15/52
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
176 words
A system for acoustic echo ranging capable of measuring bearing range and velocity of moving targets; comprising: a. a first sound transducer rotatably mounted; b. a second transducer rotatably mounted, said first and second transducers forming a rotating directional acoustic array; c. a signal source for generating a first substantially pure sine wave signal coupled to said first sound transducer; d. a means for receiving and amplifying signal echoes of a given frequency above or below said first signal received from a moving target coupled to said second sound transducer; e. means for comparing the frequencies of the transmitted signal and the echo signal and converting the difference to target velocity, said means coupled to said signal source and said receiving means; f. means of measuring range on the said received signal by measuring the delay of the signal related to the rotation speed and position of said first rotating sound transducer; and g. means for producing a signal capable of both frequency resolution and time resolution using as a reference the rotating directional acoustic array.
Claim 2
Independent Claim
176 words
A system for acoustic echo ranging capable of measuring bearing range and velocity of moving targets; comprising: a. a first sound transducer rotatably mounted; b. a second transducer rotatably mounted, said first and second transducers forming a rotating directional acoustic array; c. a signal source for generating a first substantially pure sine wave signal coupled to said first sound transducer; d. a means for receiving and amplifying signal echoes of a given frequency above or below said first signal received from a moving target coupled to said second sound transducer; e. means for comparing the frequencies of the transmitted signal and the echo signal and converting the difference to target velocity, said means coupled to said signal source and said receiving means; f. means of measuring range on the said received signal by measuring the delay of the signal related to the rotation speed and position of said first rotating sound transducer; and g. means for producing a signal capable of both frequency resolution and time resolution using as a reference the rotating directional acoustic array.
Claim 3
Dependent Claim
27 words
The system of claim 1 wherein said first sound transducer is rotated at fixed selected speeds and the second sound transducer is directed toward a desired target.
Claim 4
Dependent Claim
36 words
The system of claim 2 wherein there is provided means coupled to said receiving sound transducer for displaying the returned echoes for maximum signal strength indicating the bearing, velocity and the range of the moving target.
Claim 5
Dependent Claim
29 words
The system of claim 1 wherein there is provided means coupled to said first and second rotatably mounted sound transducers for mounting them with a fixed angular displacement therebetween.
Claim 6
Dependent Claim
34 words
The system of claim 4 wherein there is provided means coupled to said receiving sound transducer for displaying the returned echoes for maximum signal strength indicating the bearing and velocity for a selected range.
Claim 7
Dependent Claim
39 words
The system of claim 4 wherein the means for receiving the signal echoes includes at least two channels having pass bands of a given width and of a given frequency individually above and below the generated sine wave frequency.
Claim 8
Dependent Claim
27 words
The system of claim 6 wherein said pass bands are adjustable with respect to said sine wave frequency and pass band having an extremely sharp cut-off points.
Claim 9
Dependent Claim
340 words
An improved moving target echo ranging system; comprising; a. first, second and third sound transducers co-axially mounted: b. first, second and third means for rotating said sound transducers coupled respectively to said first, second and third sound transducers; c. An oscillator for generating a substantially pure sine wave at a given frequency coupled to first of said sound transducers; d. A first receiver having first and second receiving channels individually having selected pass bands above and below said generated sine wave signal frequency said pass bands variable with respect to said generated sine wave signal, said receiver connected to said second sound transducer means; e. a second receiver having third and fourth receiving channels individually having selected pass bands above and below said generated signal said pass bands variable with respect to said generated signal, said second receiver connected to said third sound transducers; f. a first display means connected to said oscillator and to said first receiver to display the time of travel of the generated signal in water from said first sound transducer to a moving target and the reflected signal to said second sound transducer; g. a second display means connected to said oscillator and to said second receiver to display the echo signal intensity of a moving target received at said first sound transducer; h. means coupled to the rotating means for rotating said first and second sound transducer with a fixed angular displacement therebetween to receive at said second sound transducer reflected signals from a moving target between a minimum and maximum distance from said co-axial sound transducer array; and i. means for positioning said sound transducer on a given bearing towards a moving target coupled to said third rotating means, said target adding or subtracting a velocity component to the generated signal so that the reflected signal is at a higher or lower frequency by an amount relative to the motion of said target said reflected signal frequency being in the pass band of said first and third or second and fourth receiving channels.
Claim 10
Dependent Claim
340 words
An improved moving target echo ranging system; comprising; a. first, second and third sound transducers co-axially mounted: b. first, second and third means for rotating said sound transducers coupled respectively to said first, second and third sound transducers; c. An oscillator for generating a substantially pure sine wave at a given frequency coupled to first of said sound transducers; d. A first receiver having first and second receiving channels individually having selected pass bands above and below said generated sine wave signal frequency said pass bands variable with respect to said generated sine wave signal, said receiver connected to said second sound transducer means; e. a second receiver having third and fourth receiving channels individually having selected pass bands above and below said generated signal said pass bands variable with respect to said generated signal, said second receiver connected to said third sound transducers; f. a first display means connected to said oscillator and to said first receiver to display the time of travel of the generated signal in water from said first sound transducer to a moving target and the reflected signal to said second sound transducer; g. a second display means connected to said oscillator and to said second receiver to display the echo signal intensity of a moving target received at said first sound transducer; h. means coupled to the rotating means for rotating said first and second sound transducer with a fixed angular displacement therebetween to receive at said second sound transducer reflected signals from a moving target between a minimum and maximum distance from said co-axial sound transducer array; and i. means for positioning said sound transducer on a given bearing towards a moving target coupled to said third rotating means, said target adding or subtracting a velocity component to the generated signal so that the reflected signal is at a higher or lower frequency by an amount relative to the motion of said target said reflected signal frequency being in the pass band of said first and third or second and fourth receiving channels.
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) | 1978-06-23 | 1978-12-23 | 1979-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-23 | 1982-12-23 | 1983-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-23 | 1986-12-23 | 1987-06-24 | $7700.00 | Window Closed / Lapsed |