Patent US3812494A successfully refreshed from Google Patents.
US3812494A
Expired / Lapsed
US
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Tri-frequency instrumentation antenna
Assignee: United States Department of the Army
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Filing: 1973-02-28
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Granted: 1974-05-21
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Expires: 1993-02-28
Abstract
Abstract The tri-frequency antenna is a multi-frequency antenna providing isolation between different frequency bands and an impedance match for all frequencies involved. It is ideally suited for use on spinning missiles because of its roll-symmetrical antenna pattern. It may be used as a combination transmitting and receiving antenna without danger of ionization at high altitudes with reasonable radiation power levels. In missiles, the missile outer surface serves as the antenna radiating elements. Associated matching networks and a common coupler allows both isolation and matching.
Inventors
- 👤 J Howell
- 👤 W Hudson
- 👤 H Krzyzewski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:35
CPC Classifications
H; H01; H01Q; H01Q1/00; H01Q1/27; H01Q1/28; H01Q1/281
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
195 words
A tri-frequency instrumentation antenna comprising: first and second frequency radiating and receiving members; impedance matching and isolation means having an input-output junction, an input junction, and an output junction, said input and output junctions being disposed for receiving doppler radar frequency energy for transmission and reception; coupling means connecting said input-output junction to said radiating and receiving members for coupling radiant energy therebetween; a high frequency band matching network having an input coupled to said coupling means and an output coupled to said second frequency radiating and receiving member for coupling preselected high frequency energy therebetween; and wherein said coupling means is an antenna feed pin coupled to said first and second radiating members for coupling energy thereto, and a coaxial cable formed in a coil emcomPassing said feed pin, the outer conductive shield of said coaxial cable coil being terminated across said first and second radiating members for controlling the reactance of the antenna; and the inner conductor of said coaxial coil having one end connected as said input to said band matching network and the other end disposed for carrying high frequency radiant energy thereto independent of energy coupled through said feed pin.
Claim 2
Dependent Claim
195 words
A tri-frequency instrumentation antenna comprising: first and second frequency radiating and receiving members; impedance matching and isolation means having an input-output junction, an input junction, and an output junction, said input and output junctions being disposed for receiving doppler radar frequency energy for transmission and reception; coupling means connecting said input-output junction to said radiating and receiving members for coupling radiant energy therebetween; a high frequency band matching network having an input coupled to said coupling means and an output coupled to said second frequency radiating and receiving member for coupling preselected high frequency energy therebetween; and wherein said coupling means is an antenna feed pin coupled to said first and second radiating members for coupling energy thereto, and a coaxial cable formed in a coil emcomPassing said feed pin, the outer conductive shield of said coaxial cable coil being terminated across said first and second radiating members for controlling the reactance of the antenna; and the inner conductor of said coaxial coil having one end connected as said input to said band matching network and the other end disposed for carrying high frequency radiant energy thereto independent of energy coupled through said feed pin.
Claim 3
Dependent Claim
62 words
An instrumentation antenna as set forth in claim 1 and further comprising a coil form for supporting said coaxial cable coil around the axis of said feed pin; said coil form being a cylindrical non-conductive member having first and second electrically conductive, apertured end members for terminating said coaxial cable shield conductor thereon and across said first and second radiating members respectively.
Claim 4
Dependent Claim
76 words
An instrumentation antenna as set forth in claim 2 wherein said matching and isolation means comprises first and second isolation tank circuits connected to said input-output junction; a first matching L filter section connected between said first tank circuit and said input junction for coupling input energy from said junction through said first tank circuit to said input-output junction; and a second matching L filter section connected between said second tank circuit and said output junction.
Claim 5
Dependent Claim
80 words
An instrumentation antenna as set forth in claim 3 wherein said band matching network comprises a quarter-wave transformer and coaxial cable serially connected between said second radiating member and said coaxial coil inner conductor for providing characteristic impedance matching therebetween, and a quarter-wave stub tuner connected between said quarter-wave transformer and said coaxial coil inner conductor for providing a short-circuit terminal at said doppler radar frequencies and thereby preventing said doppler frequencies from impinging on said coaxial coil inner conductor.
Claim 6
Dependent Claim
50 words
An antenna as set forth in claim 4 wherein said first and second frequency radiating and receiving members comprise a housing assembly encompassing said matching and isolation means, said coupling means, and said band matching network; said first and second radiating members being joined together by a non-conductive support member.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-05-20 | 1977-11-19 | 1978-05-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-20 | 1981-11-19 | 1982-05-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-20 | 1985-11-19 | 1986-05-21 | $7700.00 | Window Closed / Lapsed |