US4680591A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Helical antenna array with resonant cavity and impedance matching means
Assignee: QED Intellectual Property Ltd
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Filing: 1984-06-27
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Granted: 1987-07-14
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Expires: 2004-06-27
Abstract
Abstract An antenna is formed of four arrays each having sixteen helical antenna elements with probes located within a common resonant cavity. Thus cavity is used to combine all the outputs of elements. The elements of array are arranged over the surface of box such that the probes are located at the voltage antinodes of the resonance field patterns in order to maximize the coupling efficiency. Likewise the output probe for each cavity 6 is also located at a voltage antinode; output probe enables the signal combined in cavity to pass into a waveguide, also connected to other arrays and, for passage to the television receiver.
Inventors
- 👤 Walter J. Axford
- 👤 Francis R. Trumble
- 👤 Charles W. Turner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:04
CPC Classifications
H; H01; H01Q; H01Q1/00; H01Q1/40; H01Q21/00; H01Q21/0006; H01Q21/06; H01Q21/061; H01Q21/067
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
167 words
An antenna array comprising: a plurality of helical antenna elements, each having a straight stem end portion; means to combine signals received at the respective helical antenna elements; means to define a single resonant cavity, the single resonant cavity constituting signal-combining means; a wall member defining a surface of the single resonant cavity, said wall member having a number of apertures which communicate with the single resonant cavity and said wall member providing support for the helical antenna elements; each said helical antenna element being mounted over said wall member such that the straight stem extends through a respective aperture with the free end of the stem within the single resonant cavity, thereby to provide coupling between the elements and the cavity; electrically-conductive material, of the wall member, forming the cavity-defining surface of that wall member; means to control impedance between the helical antenna elements and the cavity; the impedance-control means being constituted by a predetermined value of thickness of the electrically-conductive material of the wall member.
Claim 2
Dependent Claim
167 words
An antenna array comprising: a plurality of helical antenna elements, each having a straight stem end portion; means to combine signals received at the respective helical antenna elements; means to define a single resonant cavity, the single resonant cavity constituting signal-combining means; a wall member defining a surface of the single resonant cavity, said wall member having a number of apertures which communicate with the single resonant cavity and said wall member providing support for the helical antenna elements; each said helical antenna element being mounted over said wall member such that the straight stem extends through a respective aperture with the free end of the stem within the single resonant cavity, thereby to provide coupling between the elements and the cavity; electrically-conductive material, of the wall member, forming the cavity-defining surface of that wall member; means to control impedance between the helical antenna elements and the cavity; the impedance-control means being constituted by a predetermined value of thickness of the electrically-conductive material of the wall member.
Claim 3
Dependent Claim
31 words
An antenna array according to claim 1, wherein the impedance-control means is contituted by an electrically-conducting lining deposited on a substrate of electrically insulating material which substrate defines said wall member.
Claim 4
Dependent Claim
36 words
An antenna array according to claim 1, wherein the impedance-control means is constituted by an electrically-conductive plate having a thickness corresponding approxiomately to one half the wavelength of microwave radiation for which the array is designed.
Claim 5
Dependent Claim
21 words
An antenna array according to claim 1, wherein the impedance-control means is constituted by an electrically-conductive plate of 8 mm thickness.
Claim 6
Dependent Claim
36 words
An antenna array according to claim 1, wherein the impedance-control means is constituted by an electrically-conductive plate having a thickness corresponding approximately to one quarter the wavelength of microwave radiation for which the array is designed.
References Cited (Backward Citations)
US2863148A
Cited
US2847672A
Cited
GB1234751A
Cited
US3509572A
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US3623118A
Cited
US4197545A
Cited
US4322731A
Cited
US4400703A
Cited
US4356497A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-07-13 | 1991-01-12 | 1991-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-13 | 1995-01-12 | 1995-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-13 | 1999-01-12 | 1999-07-14 | $7700.00 | Window Closed / Lapsed |