US4983987A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Antenna
Assignee: The General Electric Company PLC
•
Filing: 1988-12-20
•
Granted: 1991-01-08
•
Expires: 2008-12-20
Abstract
Abstract An antenna capable of producing circularly polarized radiation is formed by two non-coaxial cross dipoles.
Inventors
- 👤 Edmund W. Woloszczuk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 06:44
CPC Classifications
H; H01; H01Q; H01Q21/00; H01Q21/24
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
145 words
An antenna comprising: a pair of crossed dipoles, each dipole having a center axis and a pair of dipole arms disposed about its center axis, the pair of crossed dipoles being arranged such that the center axes are separated by a distance less than the length of the dipole arm; two three conductor feed structures, each feed structure being connected to a respective one of said pair of dipoles and having two outer conductors and a central conductor, the central conductor extending along the center axis of the respective dipole; wherein each arm of said pair of dipole arms of each dipole is formed from an extension of one of the two outer conductors of the feed structure connected to the respective dipole and one arm of each dipole is electrically connected to the central conductor of the feed structure connected to the respective dipole.
Claim 2
Dependent Claim
145 words
An antenna comprising: a pair of crossed dipoles, each dipole having a center axis and a pair of dipole arms disposed about its center axis, the pair of crossed dipoles being arranged such that the center axes are separated by a distance less than the length of the dipole arm; two three conductor feed structures, each feed structure being connected to a respective one of said pair of dipoles and having two outer conductors and a central conductor, the central conductor extending along the center axis of the respective dipole; wherein each arm of said pair of dipole arms of each dipole is formed from an extension of one of the two outer conductors of the feed structure connected to the respective dipole and one arm of each dipole is electrically connected to the central conductor of the feed structure connected to the respective dipole.
Claim 3
Dependent Claim
72 words
An antenna as defined in claim 1, wherein the two three conductor feed structures are parallel to one another and the dipole arms of a first one of the pair of dipoles are co-planer with the two outer conductors of its respective feed structure and the dipole arms of a second one of the pair of dipoles are perpendicular to the plane of the two outer conductors of its respective feed structure.
Claim 4
Dependent Claim
32 words
An antenna as defined in claim 1, wherein the pair of crossed dipoles are perpendicular to one another and are supplied with signals 90° out of phase to transmit circularly polarized radiation.
Claim 5
Dependent Claim
32 words
An antenna as defined in claim 1, wherein signals transmitted along one of the central conductors are delayed 90° in phase relative to signals transmitted along the other of said central conductors.
Claim 6
Dependent Claim
41 words
An antenna as defined in claim 4, wherein the phase difference between signals is provided by the signal path length of said one of the central conductors being longer than the signal path length of the other of the central conductors.
References Cited (Backward Citations)
US3742510A
Cited
GB1480377A
Cited
GB2048571A
Cited
EP0156684A1
Cited
GB2191044A
Cited
GB2207005A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-01-07 | 1994-07-09 | 1995-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-01-07 | 1998-07-09 | 1999-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-01-07 | 2002-07-09 | 2003-01-08 | $7700.00 | Window Closed / Lapsed |