US3813674A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cavity backed dipole-slot antenna for circular polarization
Assignee: UK Secretary of State for Defence
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Filing: 1973-01-04
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Granted: 1974-05-28
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Expires: 1993-01-04
Abstract
Abstract Aerial for receiving or transmitting circularly polarized electromagnetic radiation includes a dipole mounted substantially within the aperture of a slot and means for coupling the slot to the dipole asymmetrically. It may also include an electromagnetic cavity adjacent the coupled dipole and slot. In one embodiment the dipole is formed on one side of an insulating substrate and a narrow conductor is formed on the other side substantially opposite the dipole, with part of the dipole, the substrate, and the conductor together forming a stripline feed which may have a matching network formed by a further part of the dipole, the substrate, and the conductor.
Inventors
- 👤 M Sidford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:05
CPC Classifications
H; H01; H01Q; H01Q21/00; H01Q21/24; H01Q13/00; H01Q13/10; H01Q13/18; H01Q9/00; H01Q9/04; H01Q9/06; H01Q9/065
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
146 words
An aerial for receiving or transmitting circularly polarized electromagnetic radiation comprising an insulating substrate on one side of which is formed a dipole, said dipole being mounted substantially within the aperture of a slot antenna, means for coupling the slot antenna to the dipole asymmetrically with respect to a line of symmetry of the dipole, an electromagnetic cavity adjacent the coupled dipole and slot antenna, and a narrow conductor formed on the other side of said substrate substantially opposite the dipole and disposed such that part of the dipole, the substrate, and the conductor together form a stripline feed, said means for coupling the slot antenna to the dipole asymmetrically comprising another conductor formed on the same side of the substrate as the narrow conductor but insulatedly separated from it and positioned over the dipole and the slot antenna so as to couple them together capacitively.
Claim 2
Dependent Claim
146 words
An aerial for receiving or transmitting circularly polarized electromagnetic radiation comprising an insulating substrate on one side of which is formed a dipole, said dipole being mounted substantially within the aperture of a slot antenna, means for coupling the slot antenna to the dipole asymmetrically with respect to a line of symmetry of the dipole, an electromagnetic cavity adjacent the coupled dipole and slot antenna, and a narrow conductor formed on the other side of said substrate substantially opposite the dipole and disposed such that part of the dipole, the substrate, and the conductor together form a stripline feed, said means for coupling the slot antenna to the dipole asymmetrically comprising another conductor formed on the same side of the substrate as the narrow conductor but insulatedly separated from it and positioned over the dipole and the slot antenna so as to couple them together capacitively.
Claim 3
Dependent Claim
119 words
An aerial for receiving or transmitting circularly polarized electromagnetic radiation including a dipole mounted substantially within the aperture of a slot antenna, an electromagnetic cavity adjacent the coupled dipole and slot and having a depth of less than lambda /10, where lambda is the wavelength of the radiation, means for coupling the slot antenna to the dipole asymmetrically with respect to a line of symmetry of the dipole for determining the relative phase and amplitude of the responses of the slot antenna and the dipole to the radiation, and means connected to the dipole for feeding alternating electrical signals at the frequency of the radiation to the dipole and thus via the coupling means to excite the slot antenna.
Claim 4
Dependent Claim
119 words
An aerial for receiving or transmitting circularly polarized electromagnetic radiation including a dipole mounted substantially within the aperture of a slot antenna, an electromagnetic cavity adjacent the coupled dipole and slot and having a depth of less than lambda /10, where lambda is the wavelength of the radiation, means for coupling the slot antenna to the dipole asymmetrically with respect to a line of symmetry of the dipole for determining the relative phase and amplitude of the responses of the slot antenna and the dipole to the radiation, and means connected to the dipole for feeding alternating electrical signals at the frequency of the radiation to the dipole and thus via the coupling means to excite the slot antenna.
Claim 5
Dependent Claim
15 words
An aerial as claimed in claim 2, and wherein the dipole is a folded dipole.
Claim 6
Dependent Claim
55 words
An aerial as claimed in claim 2 and further including an insulating substrate on one side of which is formed the dipole, and a narrow conductor formed on the other side of said substrate substantially opposite the dipole, disposed such that part of the dipole the substrate and the conductor together form a stripline feed.
Claim 7
Dependent Claim
63 words
An aerial as claimed in claim 2 wherein the means for coupling the slot to the dipole asymmetrically with respect to a line of symmetry of the dipole is another conductor formed on the same side of the substrate as the narrow conductor but insulatedly separated from it and positioned over the dipole and the slot so as to couple them together capacitively.
Claim 8
Dependent Claim
39 words
An aerial as claimed in claim 2 wherein the means for coupling includes an electronic switch device for controlling the phase between the responses of the slot and the dipole to the radiation afforded by said means for coupling.
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) | 1977-05-27 | 1977-11-26 | 1978-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-27 | 1981-11-26 | 1982-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-27 | 1985-11-26 | 1986-05-28 | $7700.00 | Window Closed / Lapsed |