US4280127A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Range swath coverage method for synthetic aperture radar
Assignee: Northrop Grumman Corp
•
Filing: 1979-07-25
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Granted: 1981-07-21
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Expires: 1999-07-25
Abstract
Abstract A synthetic aperture radar antenna, which is mechanically scanned through the squint mode, is operated to a selected roll angle to optimize the alignment of the antenna beam axis or isogain line, and the line of constant doppler frequency or isodop line. The roll angle is selected as a function of the angular position of the antenna in azimuth and elevation.
Inventors
- 👤 Henry E. Lee
- 👤 Francisco J. Guillen
- 👤 R. Noel Longuemare, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:59
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/88; G01S13/89; G01S13/90; G01S13/904; G01S13/9041; G01S13/9043
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
99 words
A method of increasing the range swath coverage in an airborne synthetic aperture radar antenna that is operated by a gimbal drive mechanism to position the antenna about axes in elevation and azimuth and to position the antenna about a roll axis that is orthogonal to both the elevation and azimuth axes, said antenna being configured to project a beam that changes the area of illumination in accordance with its angular position about the roll axis, comprising positioning the antenna about the roll axis a selected angle effective to more closely align the isogain line and the isodop line.
Claim 2
Independent Claim
99 words
A method of increasing the range swath coverage in an airborne synthetic aperture radar antenna that is operated by a gimbal drive mechanism to position the antenna about axes in elevation and azimuth and to position the antenna about a roll axis that is orthogonal to both the elevation and azimuth axes, said antenna being configured to project a beam that changes the area of illumination in accordance with its angular position about the roll axis, comprising positioning the antenna about the roll axis a selected angle effective to more closely align the isogain line and the isodop line.
Claim 3
Dependent Claim
30 words
A method according to claim 1 wherein the selected roll angle about the roll axis is determined as a function of the antenna pointing angle both in azimuth and elevation.
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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) | 1984-07-20 | 1985-01-19 | 1985-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-07-20 | 1989-01-19 | 1989-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-07-20 | 1993-01-19 | 1993-07-21 | $7700.00 | Window Closed / Lapsed |