US4244036A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic stabilization for displaced phase center systems
Assignee: Northrop Grumman Corp
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Filing: 1978-12-21
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Granted: 1981-01-06
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Expires: 1998-12-21
Abstract
Abstract In moving target indication or synthetic aperture systems, double pairs of measurements of returned energy are made from displaced spatial locations to enable computation of side and angular deviation from the flight path, without the requirement for inertial navigational measuring instruments.
Inventors
- 👤 Robert S. Raven
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:45
CPC Classifications
G; G01; G01S; G01S15/00; G01S15/88; G01S15/89; G01S15/8902; G01S15/8904; G01S13/00; G01S13/88; G01S13/89; G01S13/90; G01S13/9021; G01S13/9023; G01S13/9029
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
147 words
Data correction apparatus for sensor systems adapted to travel over a target area, on a carrier vehicle, comprising: (a) an array of linearly arranged active elements, at least one of which is adapted to both transmit and receive energy; (b) means for periodically transmitting energy from said one element toward said target area during travel of said carrier and for receiving energy returns on all said elements to derive, as a result of each said transmission at least two signals corresponding to two spatial sample locations along the path of said travel; (c) said signals from one transmission nominally corresponding to the same spatial location as said signals from a subsequent transmission, but subject to relative lateral and angular deviation; and (d) means for comparing said two signals from said one transmission with said two signals from said subsequent transmission to generate at least one correction signal.
Claim 2
Dependent Claim
147 words
Data correction apparatus for sensor systems adapted to travel over a target area, on a carrier vehicle, comprising: (a) an array of linearly arranged active elements, at least one of which is adapted to both transmit and receive energy; (b) means for periodically transmitting energy from said one element toward said target area during travel of said carrier and for receiving energy returns on all said elements to derive, as a result of each said transmission at least two signals corresponding to two spatial sample locations along the path of said travel; (c) said signals from one transmission nominally corresponding to the same spatial location as said signals from a subsequent transmission, but subject to relative lateral and angular deviation; and (d) means for comparing said two signals from said one transmission with said two signals from said subsequent transmission to generate at least one correction signal.
Claim 3
Dependent Claim
52 words
Apparatus according to claim 1, wherein said means for comparing includes: (a) circuit means responsive to said comparison for generating a first signal proportional to lateral deviation of said array from a prescribed path of travel and a second signal proportional to angular deviation of said array relative to a prescribed orientation.
Claim 4
Dependent Claim
46 words
Apparatus according to claim 2 which includes (a) circuit means responsive to said first and second signals for generating a plurality of signals and for applying said plurality of signals to respective signals provided by said elements in response to said energy returns to modify same.
Claim 5
Dependent Claim
88 words
Apparatus according to claim 1 wherein: (a) said detection system is a moving target detection system; and wherein (b) said means for transmitting and receiving derives at least three signals corresponding to three spatial sample locations along said path; (c) said means for comparing being operable to compare at least one of said three signals from one transmission with one of said three signals from the subsequent transmission to generate an output signal indicative of the difference between said compared signals, said difference being indicative of target movement.
Claim 6
Dependent Claim
17 words
Apparatus according to claim 4 wherein: (a) said array is comprised of four of said active elements.
Claim 7
Dependent Claim
17 words
Apparatus according to claim 4 wherein: (a) said array is comprised of three of said active elements.
Claim 8
Dependent Claim
49 words
Apparatus according to claim 6 wherein: (a) the middle one of said three active elements is adapted to transmit a pulse of energy on a first transmission; and (b) an end one of said three active elements is adapted to transmit a pulse of energy on the subsequent transmission.
Claim 9
Dependent Claim
100 words
Apparatus according to claim 1 wherein: (a) said detection system is an acoustic synthetic aperture sonar system; and wherein (b) an end element of said array is adapted to transmit acoustic energy; (c) said array being of length L and said subsequent transmission being made when said array has traveled L/2 from said first transmission; (d) said means for transmitting and receiving derives a number of spatial samples equal to the number of said active elements; (e) the last two spatial sample signals of said one transmission being compared with the first two spatial sample signals of said subsequent transmission.
Claim 10
Dependent Claim
101 words
Apparatus according to claim 1 wherein: (a) said detection system is an acoustic synthetic aperture sonar system; and wherein (b) two end ones of said active elements are alternately adapted to transmit acoustic energy on alternate transmissions; (c) said array being of length L and said subsequent transmission being made when said array has traveled L/2 from said first transmission; (d) said means for transmitting and receiving derives a number of spatial samples equal to the number of said active elements; (e) all spatial sample signals of said one transmission being compared with all spatial sample signals of said subsequent transmission.
References Cited (Backward Citations)
GB1454368A
Cited
US3993994A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-01-06 | 1984-07-07 | 1985-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-06 | 1988-07-07 | 1989-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-06 | 1992-07-07 | 1993-01-06 | $7700.00 | Window Closed / Lapsed |