US3725940A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Horizontal vehicle mounted omnidirectional loop antenna having a shorting stub
Assignee: United States Atomic Energy Commission
•
Filing: 1972-02-08
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Granted: 1973-04-03
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Expires: 1992-02-08
Abstract
Abstract A horizontal rooftop antenna is adapted to be mounted on rolling stock or a highway truck. It is in the form of an end fed shunttype closed loop radiator tuned to frequencies between 2 and 30 MHz.
Inventors
- 👤 R Siple
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 09:34
CPC Classifications
H; H01; H01Q; H01Q7/00; H01Q7/02; H01Q1/00; H01Q1/27; H01Q1/32; H01Q1/325; H01Q1/3275
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
164 words
An end fed shunt-type radiating antenna adapted to be mounted on a vehicle roof comprising: a continuous generally rectangular open ended conductive loop, a first end of said loop being the feedpoint and connected to receive a transmitter signal through an inner conductor of a coaxial cable, an outer conductor of the coaxial cable being connected to the vehicle roof which constitutes a reflecting ground plane, a second end of said loop having a conductive stub connected thereto spaced parallel to and at a short distance from the first loop side, a conductive shorting stub positioned at substantially right angles to and joining the first side and the conductive stub at a distance from the feedpoint serving to close the loop, and an insulating supporting structure attached to the vehicle roof and to the antenna loop in the vicinity of the four corners of the loop, the supporting structure holding the antenna loop in a horizontal position at a distance above the vehicle roof.
Claim 2
Dependent Claim
164 words
An end fed shunt-type radiating antenna adapted to be mounted on a vehicle roof comprising: a continuous generally rectangular open ended conductive loop, a first end of said loop being the feedpoint and connected to receive a transmitter signal through an inner conductor of a coaxial cable, an outer conductor of the coaxial cable being connected to the vehicle roof which constitutes a reflecting ground plane, a second end of said loop having a conductive stub connected thereto spaced parallel to and at a short distance from the first loop side, a conductive shorting stub positioned at substantially right angles to and joining the first side and the conductive stub at a distance from the feedpoint serving to close the loop, and an insulating supporting structure attached to the vehicle roof and to the antenna loop in the vicinity of the four corners of the loop, the supporting structure holding the antenna loop in a horizontal position at a distance above the vehicle roof.
Claim 3
Dependent Claim
26 words
The radiating antenna structure of claim 1 wherein the loop is made of stainless steel tubing and the supporting structure is made of polyvinyl chloride tubing.
Claim 4
Dependent Claim
29 words
The radiating antenna structure of claim 2 wherein the supporting structure is hinged to the top of the vehicle so that the antenna structure may be raised and lowered.
Claim 5
Dependent Claim
23 words
The radiating antenna structure of claim 3 wherein a hydraulic cylinder Having a remote control operates to raise and lower the supporting structure.
Claim 6
Dependent Claim
23 words
The radiating antenna structure of claim 1 wherein the loop is supported at a distance of about 15 inches above the vehicle roof.
References Cited (Backward Citations)
US2221939A
Cited
US3299428A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |