Patent US3750181A successfully refreshed from Google Patents.
US3750181A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ground independent antenna
Assignee: Radionics Inc
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Filing: 1971-09-07
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Granted: 1973-07-31
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Expires: 1991-09-07
Abstract
Abstract A ground independent UHF antenna is described which has upper and lower coaxial radiators. The upper radiator provides a coaxial feed cavity presenting both inductance and capacitance so as to provide a broad bandwidth of operation. The lower radiator defines a choke cavity which affords ground independent operation.
Inventors
- 👤 J Kuecken
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:21
CPC Classifications
H; H01; H01Q; H01Q1/00; H01Q1/50; H01Q9/00; H01Q9/04; H01Q9/16; H01Q9/28
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
132 words
In a ground independent UHF antenna, the combination comprising: a. a conductive pipe; b. upper and lower radiators disposed around said pipe and spaced from each other to form upper and lower coaxial cavities and defining upper radiator inductance and lower radiator inductance Lr respectively; c. a line for carrying signals, said line being disposed inside said pipe and extending upwardly along said pipe into said upper cavity, said line also extending across said upper cavity and being connected to said upper radiator and defining an unbalance inductor Lc said line connection being selected to obtain a desired characteristic impedance for the antenna and d. a capacitor disposed in said line and coupling said upper cavity and having a capacitance selected to substantially tune out said unbalance inductance Lc of said line.
Claim 2
Dependent Claim
132 words
In a ground independent UHF antenna, the combination comprising: a. a conductive pipe; b. upper and lower radiators disposed around said pipe and spaced from each other to form upper and lower coaxial cavities and defining upper radiator inductance and lower radiator inductance Lr respectively; c. a line for carrying signals, said line being disposed inside said pipe and extending upwardly along said pipe into said upper cavity, said line also extending across said upper cavity and being connected to said upper radiator and defining an unbalance inductor Lc said line connection being selected to obtain a desired characteristic impedance for the antenna and d. a capacitor disposed in said line and coupling said upper cavity and having a capacitance selected to substantially tune out said unbalance inductance Lc of said line.
Claim 3
Dependent Claim
66 words
The invention as set forth in claim 1 wherein the connection to said upper radiator is at a point along the length of said upper radiator such that the ratio of the distance between said point and the upper end of said upper radiator and the length of said upper radiator corresponds to the desired impedance of said antenna at the center of its operating band.
Claim 4
Dependent Claim
15 words
The invention as set forth in cLaim 1 wherein said line is a coaxial cable.
Claim 5
Dependent Claim
47 words
The invention as set forth in claim 3 wherein said cable has an inner and outer conductor, and opening in said pipe out of which the center conductor of said cable extends across said cavity to said upper radiator, said outer conductor being connected to said pipe.
Claim 6
Dependent Claim
25 words
The invention as set forth in claim 4 wherein the connection between said outer conductor of said cable and said pipe is at said opening.
Claim 7
Dependent Claim
31 words
The invention as set forth in claim 1 wherein said radiators are sleeves of conductive material coaxial with said pipe and having a disc shaped upper ends connected to said pipe.
Claim 8
Dependent Claim
24 words
The invention as set forth in claim 6 wherein said pipe extends through the disc at the upper end of said upper radiator sleeve.
Claim 9
Dependent Claim
24 words
The invention as set forth in claim 1 wherein the spacing between said upper and lower radiator defines a feed gap for said antenna.
Claim 10
Dependent Claim
21 words
The invention as set forth in claim 8 wherein said feed gap is approximately one-fifth the length of said individual radiators.
Claim 11
Dependent Claim
15 words
The invention as set forth in claim 9 wherein said radiators are of equal length.
Claim 12
Dependent Claim
17 words
The invention as set forth in claim 1 wherein the diameter of said radiators is relatively large.
Claim 13
Dependent Claim
33 words
The invention as set forth in claim 11 wherein said radiator diameter is approximately 0.035 times the wave length at the lower end of the band of frequency over which the antenna operates.
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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) | 1976-07-30 | 1977-01-29 | 1977-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-30 | 1981-01-29 | 1981-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-30 | 1985-01-29 | 1985-07-31 | $7700.00 | Window Closed / Lapsed |