US3947770A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Broadband omnidirectional RF field intensity indicating device
Assignee: United States Department of the Navy
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Filing: 1974-07-12
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Granted: 1976-03-30
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Expires: 1994-07-12
Abstract
Abstract A device for indicating the intensity of the vertical component of an incnt electromagnetic field independently of the frequency or the direction of the field uses a dual-loop antenna, current transformers and a means for combining voltage signals. The two antenna loops are planar and the planes of the loops are disposed orthogonally to each other. The loops are arranged to intersect at a common central axis, and the loops are thus symmetrically disposed about the axis. When a source of electromagnetic radiation is incident on the antenna, a current is generated in the loops which is then transformed into a voltage and combined to produce an output which is independent of frequency, of the direction of the field, and is thus representative of the total vertical field intensity.
Inventors
- 👤 John F. Cavanagh
- 👤 Dennis E. Vaught
- 👤 Hugh K. Wolfe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 04:16
CPC Classifications
G; G01; G01R; G01R29/00; G01R29/08; G01R29/0864; G01R29/0878; H; H01; H01Q; H01Q21/00; H01Q21/24; H01Q21/245
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
139 words
A broadband omnidirectional electromagnetic-field intensity indicating device operating in the 2 MHz to 32 MHz frequency range comprising: an antenna having two planar conductive loops, the planes of said loops being orthogonally disposed, and said planes intersecting to form an axis about which the loops are symmetrically disposed, wherein an incident electromagnetic field will generate a current in each of the loops; two current transformers, one connected to each of the loops to convert the current therein to proportional voltage signals; a square law detector; a summing square rooter, said square law detector and said summing square rooter combining the voltage signals to provide an output signal independent of the angle of arrival of and the frequency of the incident electromagnetic field, and representative of the total resultant intensity of the field; and, means for indicating the output signal.
Claim 2
Dependent Claim
139 words
A broadband omnidirectional electromagnetic-field intensity indicating device operating in the 2 MHz to 32 MHz frequency range comprising: an antenna having two planar conductive loops, the planes of said loops being orthogonally disposed, and said planes intersecting to form an axis about which the loops are symmetrically disposed, wherein an incident electromagnetic field will generate a current in each of the loops; two current transformers, one connected to each of the loops to convert the current therein to proportional voltage signals; a square law detector; a summing square rooter, said square law detector and said summing square rooter combining the voltage signals to provide an output signal independent of the angle of arrival of and the frequency of the incident electromagnetic field, and representative of the total resultant intensity of the field; and, means for indicating the output signal.
Claim 3
Dependent Claim
126 words
A broadband omnidirectional electromagnetic-field intensity indicating device operating in the 2 MHz to 32 MHz frequency range comprising: an antenna having two planar conductive loops, the planes of said loops being orthogonally disposed, and said planes intersecting to form an axis about which the loops are symmetrically disposed, wherein an incident electromagnetic field will generate a current in each of the loops; two current transformers, one connected to each of the loops to convert the current therein to proportional voltage signals; a quad-hybrid wherein the voltage signals are combined to provide an output signal independent of the angle of arrival of and the frequency of the incident electromagnetic field, and representative of the total resultant intensity of the field; and, means for indicating the output signal.
Claim 4
Dependent Claim
126 words
A broadband omnidirectional electromagnetic-field intensity indicating device operating in the 2 MHz to 32 MHz frequency range comprising: an antenna having two planar conductive loops, the planes of said loops being orthogonally disposed, and said planes intersecting to form an axis about which the loops are symmetrically disposed, wherein an incident electromagnetic field will generate a current in each of the loops; two current transformers, one connected to each of the loops to convert the current therein to proportional voltage signals; a quad-hybrid wherein the voltage signals are combined to provide an output signal independent of the angle of arrival of and the frequency of the incident electromagnetic field, and representative of the total resultant intensity of the field; and, means for indicating the output signal.
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) | 1979-03-30 | 1979-09-29 | 1980-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-30 | 1983-09-29 | 1984-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-30 | 1987-09-29 | 1988-03-30 | $7700.00 | Window Closed / Lapsed |