Patent US4531128A successfully refreshed from Google Patents.
US4531128A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Buoyant radar reflector
Assignee: United States Department of the Navy
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Filing: 1982-07-26
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Granted: 1985-07-23
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Expires: 2002-07-26
Abstract
Abstract A radar reflective target consisting of a cluster of square corner reflecs configured in a cubical shape. The reflector is comprised of eight smaller blocks of lightweight radar-transparent material, such as plastic foam, with planar reflective surfaces, such as metal foil embedded between the interior faces of the individual blocks. A radar-transparent waterproof covering can be provided to protect the assembled unit.
Inventors
- 👤 Dean L. Mensa
- 👤 Dale C. Moss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:39
CPC Classifications
H; H01; H01Q; H01Q15/00; H01Q15/14; H01Q15/18
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
179 words
A lightweight, buoyant and omnidirectional radar augmentation device which prevents degradation of cross-section caused by lack of flatness and orthogonality of the reflecting surfaces, comprising: a. a solid cubical assembly formed from eight individual equal sized cubes of rigid, lightweight, buoyant, radar-transparent material; b. at least one thin planar layer of highly radar reflective material between each adjoining internal surface of said eight cubes of radar-transparent material forming said solid cubical assembly; said radar reflective material between the adjoining surfaces forming an internal assembly of eight square corner radar reflectors operable to produce a relatively larger radar echo in comparison to its size; said rigid cubes of radar-transparent material preventing warp and distortion of the flat radar reflective material surfaces while maintaining the internal corner radar reflector surfaces flat and orthogonal; c. means for retaining said eight individual cubes of radar-transparent material and said thin planar layers of highly radar reflective material together in said solid cubical assembly; each side of said cubical assembly being twice the length of a single one of said eight cubes of radar-transparent material.
Claim 2
Dependent Claim
179 words
A lightweight, buoyant and omnidirectional radar augmentation device which prevents degradation of cross-section caused by lack of flatness and orthogonality of the reflecting surfaces, comprising: a. a solid cubical assembly formed from eight individual equal sized cubes of rigid, lightweight, buoyant, radar-transparent material; b. at least one thin planar layer of highly radar reflective material between each adjoining internal surface of said eight cubes of radar-transparent material forming said solid cubical assembly; said radar reflective material between the adjoining surfaces forming an internal assembly of eight square corner radar reflectors operable to produce a relatively larger radar echo in comparison to its size; said rigid cubes of radar-transparent material preventing warp and distortion of the flat radar reflective material surfaces while maintaining the internal corner radar reflector surfaces flat and orthogonal; c. means for retaining said eight individual cubes of radar-transparent material and said thin planar layers of highly radar reflective material together in said solid cubical assembly; each side of said cubical assembly being twice the length of a single one of said eight cubes of radar-transparent material.
Claim 3
Dependent Claim
24 words
A radar augmentation device as in claim 1 wherein said cubes of rigid radar-transparent material are made from low density, low dielectric foamed plastic.
Claim 4
Dependent Claim
17 words
A radar augmentation device as in claim 1 wherein said cubes of rigid radar-transparent material are waterproof.
Claim 5
Dependent Claim
43 words
A radar augmentation device as in claim 1 wherein said at least one thin layer of radar reflective material between each adjoining internal surface of said individual cubes of rigid radar-transparent material forming said solid cubical assembly is comprised of thin metallic foil.
Claim 6
Dependent Claim
44 words
A radar augmentation device as in claim 1 wherein said at least one thin layer of radar reflective material between each adjoining internal surface of said individual cubes of rigid radar-transparent material forming said solid cubical assembly is comprised of a thin metallic paint.
Claim 7
Dependent Claim
42 words
A radar augmentation device as in claim 1 wherein said at least one thin layer of radar reflective material between each adjoining internal surface of said individual cubes of rigid radar-transparent material forming said solid cubical assembly is a thin metallic coating.
Claim 8
Dependent Claim
37 words
A radar augmentation device as in claim 1 wherein said means for retaining said radar-transparent cubes and said radar reflective surfaces together in a larger said solid cubical assembly is a thin layer of adhesive cement material.
Claim 9
Dependent Claim
25 words
A radar augmentation device as in claim 1 wherein the outer surface of said solid cubical assembly is coated with a radar transparent waterproof coating.
Claim 10
Dependent Claim
33 words
A radar augmentation device as in claim 1 wherein said solid cubical assembly is buoyant and operable to be floated in the sea as a surface target with constant orientation, giving hemispherical coverage.
Claim 11
Dependent Claim
31 words
A radar augmentation device as in claim 1 wherein all opposing corner reflectors of said solid cubical assembly together provide virtually spherical response thus rendering the device effective over all angles.
Claim 12
Dependent Claim
24 words
A radar augmentation device as in claim 1 wherein said solid cubical assembly is buoyant and operable as a radar reflective personnel flotation device.
Claim 13
Dependent Claim
41 words
A radar augmentation device as in claim 1 wherein physical deformation of the outer radar-transparent material surfaces of said solid cubical assembly will not degrade the performance of the reflective surfaces internal to the solid cubical assembly beyond said outer surfaces.
Claim 14
Independent Claim
112 words
The method of making a lightweight, buoyant and omnidirectional radar augmentation device, comprising: a. preparing eight individual equal-sized solid cubes of rigid, lightweight, buoyant and waterproof radar-transparent material; b. preparing at least eight planar radar reflective surfaces of highly radar reflective material; c. assembling said eight cubes of radar transparent material into a larger cubical assembly with at least one of said eight planar highly radar-reflective surfaces between each adjoining internal surface of said larger cubical assembly to form a solid cubical assembly with flat internal corner radar reflective surfaces which do not warp or distort and thus prevents signal degradation caused by lack of flatness and orthogonally of the reflective surfaces.
Claim 15
Independent Claim
112 words
The method of making a lightweight, buoyant and omnidirectional radar augmentation device, comprising: a. preparing eight individual equal-sized solid cubes of rigid, lightweight, buoyant and waterproof radar-transparent material; b. preparing at least eight planar radar reflective surfaces of highly radar reflective material; c. assembling said eight cubes of radar transparent material into a larger cubical assembly with at least one of said eight planar highly radar-reflective surfaces between each adjoining internal surface of said larger cubical assembly to form a solid cubical assembly with flat internal corner radar reflective surfaces which do not warp or distort and thus prevents signal degradation caused by lack of flatness and orthogonally of the reflective surfaces.
Claim 16
Dependent Claim
28 words
A method as in claim 13 wherein said planar radar reflective surfaces are each equal in size to one side of one of said eight equal sized cubes.
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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) | 1988-07-22 | 1989-01-21 | 1989-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-22 | 1993-01-21 | 1993-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-22 | 1997-01-21 | 1997-07-23 | $7700.00 | Window Closed / Lapsed |