Patent US3683390A successfully refreshed from Google Patents.
US3683390A
Expired / Lapsed
US
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Hf broadband omnidirectional antenna
Assignee: Collins Radio Co
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Filing: 1971-04-26
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Granted: 1972-08-08
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Expires: 1991-04-26
Abstract
Abstract An HF antenna providing high-angle skywave radiation at the lower end of the 2 MHz to 30 MHz band and low-angle skywave radiation at the upper frequencies with substantially gapless coverage in range from 0 to 1,000 miles with pattern characteristics optimized for propagation conditions. It utilizes predominantly horizontal polarization in minimizing ground losses in a log-periodic dipole array with elements lying in two orthogonal vertical planes with the apex substantially at ground level. It is an array with the phase center approximately a quarter-wavelength above ground at the lower frequencies and thereby near-vertical radiation for the short path circuits. Then as the frequency increases from 2 MHz to 6 MHz, the phase center increases from a quarter-wavelength above ground to near a halfwavelength above ground, providing lower angle radiation with omnidirectional characteristics. Antenna input impedance is from 50 ohms unbalanced coax line through an impedance transforming balun to 200 ohms balanced having VSWR with respect to the 50 ohm input line of less than 2.5 to 1. A single supporting tower occupying a near-minimum space volume is employed with phase controlled not only between orthogonal element bays but also between elements in each bay with one quarter phase spacing of elements so as to attain a desired elliptical polarization propagation characteristic.
Inventors
- 👤 Terry S Cory
- 👤 William A Kennedy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 20:09
CPC Classifications
H; H01; H01Q; H01Q11/00; H01Q11/02; H01Q11/10
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
276 words
In an HF antenna operational through a substantial portion of a 2 MHz to 30 MHz frequency range; a log-periodic dipole array with elements lying in orthogonal vertical planes with the apex approaching ground; a single structural fabricated mast tower vertically mounted over a ground plane with the tower base resting on a tower mounting pad at the ground; four equally spaced guy assemblies connected to an upper portion of the tower and extended to and tensioned to four individual outer guy anchor means in the ground; four individual catenary rope assemblies one connected to each of said guy assemblies and connected to individual catenary rope anchor means adjacent said tower mounting pad; signal feed means for said antenna including a vertically extended two sided balanced transmission line mounted by said tower mast; log periodic radiating elements mounted in pairs with inner ends mounted by individual interconnect means at the tower center and extended to outer end connection with oppositely extended catenary rope assemblies; with said pairs of log periodic radiating elements being alternated between vertical orthogonal planes defined generally by said opposite guy assemblies and opposite catenary rope assemblies and the radiating elements connected to the opposite pairs of catenary rope assemblies; and with feed connection from the two sides of said balanced transmission line being a 180* phase related feed to the opposite sides of each pair of radiating elements and with the feed spacing along said balanced transmission line of successively higher radiating element pairs in the antenna being approximately a 90* phase shift successively resulting in a spiral feed up the antenna to successively higher and higher element pairs in the antenna.
Claim 2
Dependent Claim
276 words
In an HF antenna operational through a substantial portion of a 2 MHz to 30 MHz frequency range; a log-periodic dipole array with elements lying in orthogonal vertical planes with the apex approaching ground; a single structural fabricated mast tower vertically mounted over a ground plane with the tower base resting on a tower mounting pad at the ground; four equally spaced guy assemblies connected to an upper portion of the tower and extended to and tensioned to four individual outer guy anchor means in the ground; four individual catenary rope assemblies one connected to each of said guy assemblies and connected to individual catenary rope anchor means adjacent said tower mounting pad; signal feed means for said antenna including a vertically extended two sided balanced transmission line mounted by said tower mast; log periodic radiating elements mounted in pairs with inner ends mounted by individual interconnect means at the tower center and extended to outer end connection with oppositely extended catenary rope assemblies; with said pairs of log periodic radiating elements being alternated between vertical orthogonal planes defined generally by said opposite guy assemblies and opposite catenary rope assemblies and the radiating elements connected to the opposite pairs of catenary rope assemblies; and with feed connection from the two sides of said balanced transmission line being a 180* phase related feed to the opposite sides of each pair of radiating elements and with the feed spacing along said balanced transmission line of successively higher radiating element pairs in the antenna being approximately a 90* phase shift successively resulting in a spiral feed up the antenna to successively higher and higher element pairs in the antenna.
Claim 3
Dependent Claim
58 words
The HF antenna of claim 1, wherein the antenna radiation elements are predominantly horizontally polarized and use the ground to form the radiation patterns that vary in take off angle from overhead high-angle skywave radiation at the lower end of the 2 MHz to 30 MHz frequency range of operation to low-angle skywave radiation at the upper frequencies.
Claim 4
Dependent Claim
70 words
The HF antenna of claim 2, wherein the log periOdic radiating elements are positioned by pairs with the highest frequency shortest radiating element pair the lowest element pair adjacent the antenna lower apex ground end with the radiating element pairs progressively being longer in their successive spacings higher and higher through the antenna to the lowest frequency longest radiating element pair as the top radiating element pair in the antenna.
Claim 5
Dependent Claim
48 words
The HF antenna of claim 3, wherein the log periodic radiating element pairs are proportioned and positioned to insure phase center shift from approximately a quarter-wavelength above ground at the lower frequencies to a half-wavelength above ground with frequency increase from approximately 2 MHz to approximately 6 MHz.
Claim 6
Dependent Claim
45 words
The HF antenna of claim 4, wherein said log periodic radiating element pairs include a plurality of said radiating element pairs with single wire radiating elements extended to outer end connection with insulating interconnect means at their outer ends mounted on respective catenary rope assemblies.
Claim 7
Dependent Claim
70 words
The HF antenna of claim 5, wherein said log periodic radiating element pairs also include a plurality of broad radiating elements with a plurality of radiating element wires included in each broad radiating element; said broad radiating element pairs being larger lower frequency radiating elements than the longest single wire radiating element; and with said broad radiating element pairs positioned above the highest single wire radiating element in the antenna.
Claim 8
Dependent Claim
80 words
The HF antenna of claim 6, wherein the topmost pair of radiating elements, as the longest, lowest frequency pair of radiating elements, are canted at a downward angle from their common interconnect at the antenna center to outer end connection with respective catenary rope assemblies closely adjacent the connection of said catenary rope assemblies with the respective guy assemblies; and with the catenary rope assembly to guy assembly interconnect connections being at the mid region of the respective guy assemblies.
Claim 9
Dependent Claim
56 words
The HF antenna of claim 7, wherein the pairs of radiating elements vary in the rate of downward canted angle from a maximum with the topmost pair progressively less and less successively from radiating element pair to pair down the antenna to substantially horizontal radiating elements as the lowermost highest frequency radiating element pair is approached.
Claim 10
Dependent Claim
31 words
The HF antenna of claim 6, wherein outer ends of radiating element wires in individual units of a plurality of said broad radiating elements are electrically interconnected by conductive material means.
Claim 11
Dependent Claim
27 words
The HF antenna of claim 9, wherein a plurality of said broad radiating elements are two wire elements having said conductive material interconnect at their outer ends.
Claim 12
Dependent Claim
54 words
The HF antenna of claim 6, wherein the plurality of radiating element wires in each side of at least one pair of said broad radiating elements are sufficiently long and so spaced as to be so inductively coupled as to appear to have conductive material interconnect between element wire ends in each respective side.
Claim 13
Dependent Claim
44 words
The HF antenna of claim 11, wherein the pair of broad radiating elements having inductive interconnect between element wires in each respective side is the topmost pair of broad radiating elements in the antenna; and with each side having three inductively coupled element wires.
Claim 14
Dependent Claim
122 words
The HF antenna of claim 7, wherein said individual interconnect means is in the form of an interconnect structure having a center structure fastened to a structural support member vertically extended substantially along the vertical epicenter of the antenna, and opposite side insulating material arms pivotally connected by individual side pivot mount means to said interconnect means center structure; radiating element wire inner end fastening means mounted on the outer end of each of said insulating material arms; and said individual fastening means electrically interconnecting jumper feed lines from respeCtive sides of said balanced transmission line and the inner ends of respective radiating wires structurally supported by said wire inner end fastening means on the outer ends of said insulating material arms.
Claim 15
Dependent Claim
50 words
The HF antenna of claim 13, wherein the said structural support member is a support cable tautly vertically extended through the antenna mast from a mast bottom plate through the position range of said radiating elements from bottom to top to connection in the top portion of the antenna mast.
Claim 16
Dependent Claim
53 words
The HF antenna of claim 14, wherein each side of said balanced transmission line is a three parallel wire side with conductive electrical interconnect through a feed jumper lead connective clamp in the transmission line to radiating element wire inner end jumper interconnect feed for all radiating elements up and down the antenna.
Claim 17
Dependent Claim
66 words
The HF antenna of claim 15, wherein said two three wire sides of the balanced transmission line are supported in vertical spaced apart relation extended between an upper yoke assembly and a lower yoke assembly; and a balun fed by an unbalanced coaxial transmission line, and with the balun having a balanced two wire output electrically connected respectively to opposite sides of said balanced transmission line.
References Cited (Backward Citations)
US3221332A
Cited
US3181161A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-08 | 1976-02-07 | 1976-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-08 | 1980-02-07 | 1980-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-08 | 1984-02-07 | 1984-08-08 | $7700.00 | Window Closed / Lapsed |