US4933678A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of detecting oil spills at sea using a shipborne navigational radar
Assignee: United States Department of the Interior
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Filing: 1989-05-30
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Granted: 1990-06-12
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Expires: 2009-05-30
Abstract
Abstract A method is provided wherein standard shipborne navigational radar is used for the purpose of detecting oil-spills on the sea. A homogenous sea-return image is obtained by selectively reducing the sea-clutter, rain, and haze filters of the radar while selectively increasing the gain of the radar. Because oil-spills on the surface of the water minimize the backscatter of radar waves, the location of an oil-spill may be determined by identifying characteristic distortions in the form of zones of diminished sea-return in the homogenous sea-return image. A moving oil spill may be tracked with repeated observations.
Inventors
- 👤 Edward J. Tennyson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 04:21
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/88
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
192 words
A method for relatively long range tracking of the location of petroleum and petroleum products on a body of water using a radar apparatus including filter means, including a sea-return filter, and haze and rain filters, for filtering radar return signals, gain control means for varying the amplification of the radar return signals, and a viewing scope for viewing said radar return signals, said method comprising: transmitting radar signals onto the surface of a body of water; receiving return radar signals backscattered from the body of water; imaging said radar return signals on said radar scope to enable viewing of wave patterns corresponding to said return signals; selectively reducing the filtering of said return signals provided by said sea-return filter and said haze and rain filters while selectively controlling said gain control mains to vary the amplitude of said radar return signals so to produce a homogeneous wave pattern at least throughout the central region of said radar scope while preventing the image on the scope from becoming bright throughout; and detecting any distortions in said homogenous wave pattern caused by the presence of petroleum products on the rough body of water.
Claim 2
Independent Claim
192 words
A method for relatively long range tracking of the location of petroleum and petroleum products on a body of water using a radar apparatus including filter means, including a sea-return filter, and haze and rain filters, for filtering radar return signals, gain control means for varying the amplification of the radar return signals, and a viewing scope for viewing said radar return signals, said method comprising: transmitting radar signals onto the surface of a body of water; receiving return radar signals backscattered from the body of water; imaging said radar return signals on said radar scope to enable viewing of wave patterns corresponding to said return signals; selectively reducing the filtering of said return signals provided by said sea-return filter and said haze and rain filters while selectively controlling said gain control mains to vary the amplitude of said radar return signals so to produce a homogeneous wave pattern at least throughout the central region of said radar scope while preventing the image on the scope from becoming bright throughout; and detecting any distortions in said homogenous wave pattern caused by the presence of petroleum products on the rough body of water.
Claim 3
Independent Claim
91 words
A method of tracking an oil-spill at sea, said method comprising: positioning a radar, having variable gain and having a sea-clutter filter, in the vicinity of the oil-spill; transmitting radar signals from said radar onto the sea; receiving return signals from the sea in response to the transmitted radar signals; selectively controlling said sea clutter filter while selectively increasing said gain of the radar so to provide a homogenous radar return from the sea; and detecting any distortions in the homogenous return caused by the presence of oil on the sea.
Claim 4
Independent Claim
91 words
A method of tracking an oil-spill at sea, said method comprising: positioning a radar, having variable gain and having a sea-clutter filter, in the vicinity of the oil-spill; transmitting radar signals from said radar onto the sea; receiving return signals from the sea in response to the transmitted radar signals; selectively controlling said sea clutter filter while selectively increasing said gain of the radar so to provide a homogenous radar return from the sea; and detecting any distortions in the homogenous return caused by the presence of oil on the sea.
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) | 1993-06-11 | 1993-12-11 | 1994-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-11 | 1997-12-11 | 1998-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-11 | 2001-12-11 | 2002-06-12 | $7700.00 | Window Closed / Lapsed |