US5182155A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radome structure providing high ballistic protection with low signal loss
Assignee: ITT Inc
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Filing: 1991-04-15
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Granted: 1993-01-26
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Expires: 2011-04-15
Abstract
Abstract A radome (12) has a composite wall structure including alternating layers of extended chain polyethylene (ECPE) fiber laminate material (26,30) which provides high ballistic protection with low RF signal loss, and fiberglass honeycomb core material (28) which provides high structural rigidity. An electronics assembly (18) and antenna elements (20) are mounted inside the radome (12), with the antenna elements (20) spaced between the electronics assembly (18) and the radome wall structure. A backing plate (24) including a layer of the laminate material (32) and an electrically conductive ground plane (34) are spaced between the electronics assembly (18) and the antenna elements (20). The numbers and thicknesses of the layers of laminate material (26,30) and core material (28) in the wall structure are selected such that the combined thickness of the layers of laminate material (26,30) has a maximum value at which the RF signal loss through the wall structure at a predetermined frequency is below an acceptable value. The backing plate (24) provides even greater ballistic protection for the electronics assembly (18).
Inventors
- 👤 Bob J. Roe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:29
CPC Classifications
B; B32; B32B; B32B3/00; B32B3/10; B32B3/12; B32B17/00; B32B17/02; B32B7/00; B32B7/04; B32B7/12; F; F41; F41H; F41H5/00; F41H5/02; F41H5/04; F41H5/0471; F41H5/0485; F42; F42B; F42B15/00; F42B15/08; H; H01; H01Q; H01Q1/00; H01Q1/42; B32B2250/00; B32B2250/40; B32B2262/00; B32B2262/02; B32B2262/0253; B32B2262/10; B32B2262/101; B32B2571/00; Y; Y10; Y10S; Y10S428/00; Y10S428/911; Y10T; Y10T428/00; Y10T428/24; Y10T428/24149
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
101 words
A ballistic protection structure for a radar system including an electronic unit and an antenna element, comprising: a radome including a composite wall structure having alternating layers of extended chain polyethylene fiber laminate material and honeycomb core material, the electronic unit and antenna element being disposed inside the radome such that the antenna element is spaced between the electronic unit and the wall structure; and a backing plate disposed inside the radome between the electronic unit and the antenna element, the backing plate in combination with the wall structure providing a predetermined limit value of ballistic protection for the electronic unit.
Claim 2
Dependent Claim
101 words
A ballistic protection structure for a radar system including an electronic unit and an antenna element, comprising: a radome including a composite wall structure having alternating layers of extended chain polyethylene fiber laminate material and honeycomb core material, the electronic unit and antenna element being disposed inside the radome such that the antenna element is spaced between the electronic unit and the wall structure; and a backing plate disposed inside the radome between the electronic unit and the antenna element, the backing plate in combination with the wall structure providing a predetermined limit value of ballistic protection for the electronic unit.
Claim 3
Dependent Claim
80 words
A ballistic protection structure as in claim 1, in which: said laminate material has a dielectric constant which is higher than a dielectric constant of said core material; and numbers and thicknesses of the layers of said laminate material and said core material are selected such that a combined thickness of the layers of said laminate material has a maximum value at which the electromagnetic signal loss through the wall structure at a predetermined frequency is below a predetermined value.
Claim 4
Dependent Claim
38 words
A ballistic protection structure as in claim 2, in which said laminate material is selected such that the dielectric constant thereof is no greater than approximately 2.5 and the loss tangent thereof is no greater than approximately 0.002.
Claim 5
Dependent Claim
15 words
A ballistic protection structure as in claim 2, in which said core material comprises fiberglass.
Claim 6
Dependent Claim
61 words
A ballistic protection structure as in claim 2, in which the wall structure comprises: a center layer of said laminate material; first and second core layers of said core material adhered to opposite surfaces of the center layer respectively; and first and second outer layers of said laminate material adhered to outer surfaces of the first and second core layers respectively.
Claim 7
Dependent Claim
31 words
A ballistic protection structure as in claim 5, in which the first and second core layers each have a thickness which is equal to approximately 1/4 wavelength at said predetermined frequency.
Claim 8
Dependent Claim
30 words
A ballistic protection structure as in claim 5, in which said thickness of the center layer is approximately twice said thickness of each of the first and second outer layers.
Claim 9
Dependent Claim
41 words
A ballistic protection structure as in claim 5, in which said thickness of the center layer is approximately 1.04 cm, said thickness of the core layers is approximately 0.63 cm, and said thickness of the outer layers is approximately 0.30 cm.
Claim 10
Dependent Claim
49 words
A ballistic protection structure as in claim 1, in which the backing plate comprises: a ballistic protection layer of said laminate material; and a ground plane layer formed of an electrically conductive material adhered to a surface of the ballistic protection layer which faces away from the electronic unit.
Claim 11
Dependent Claim
32 words
A ballistic protection structure as in claim 9, in which: the ballistic protection layer is approximately 1.27 cm thick; and the ground plane layer comprises aluminum and is approximately 0.10 cm thick.
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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) | 1996-01-26 | 1996-07-27 | 1997-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-01-26 | 2000-07-27 | 2001-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-01-26 | 2004-07-27 | 2005-01-26 | $7700.00 | Window Closed / Lapsed |