Communications: radio wave antennas – Antennas – Logarithmically periodic
Patent
1982-12-10
1986-08-26
Lieberman, Eli
Communications: radio wave antennas
Antennas
Logarithmically periodic
343846, 343895, H01Q 148, H01Q 136
Patent
active
046085726
ABSTRACT:
To optimize antenna bandwidth and efficiency in broad-band antenna elements of the planar, multiarm spiral and log periodic types, a conically shaped ground plane characterized by progressively sized circumferential chokes, is arranged on a common axis with the axial center of the spiral or log periodic elements so that the electrical spacing between the excited regions of the log periodic of spiral elements and the ground plane maintains a constant one-quarter wavelength relationship. The progressively sized circumferential chokes on the ground plane cut off the flow of excessive radial currents along the ground plane surface to achieve an improved mix of excitation and reexcitation modes. In one embodiment, the circumferential chokes on the conical ground plane are partially shunted by shunting strips that electrically or capacitively bridge the choke walls to reestablish limited radial currents along the ground plane for sustaining certain desirable antenna modes. In another disclosed embodiment, the equivalent one-quarter wavelength relationship between the driven spiral or log elements and the reflecting ground plane is maintained in an antenna structure in which the driven elements are disposed on the surface of a dielectrically shaped cone and the ground plane and progressively sized circumferential chokes are arranged in a generally planar array. In still another disclosed embodiment, the circumferential, progressively sized chokes are disposed on the interior reflective surface of a center-fed antenna horn, wherein the array of chokes has the effect of broad-banding the otherwise inherently narrow band characteristics of the horn.
REFERENCES:
patent: 2112287 (1938-03-01), Hansell et al.
patent: 2297513 (1942-09-01), Von Baeyer
patent: 2368663 (1945-02-01), Kandoian
patent: 2650985 (1953-09-01), Rust et al.
patent: 2724052 (1955-11-01), Boyer
patent: 2764757 (1956-09-01), Rust et al.
patent: 2785397 (1957-03-01), Rust et al.
patent: 2820221 (1958-01-01), Broussaud
patent: 3131394 (1964-04-01), Wheeler
patent: 3162858 (1964-12-01), Cutler
patent: 3192531 (1965-06-01), Cox et al.
patent: 3262121 (1966-07-01), Holloway
patent: 3266044 (1966-08-01), Bresler
patent: 3358288 (1967-12-01), Dubost et al.
patent: 3434146 (1969-03-01), Petrich
patent: 3555554 (1969-03-01), Kuo
patent: 3588903 (1971-06-01), Hampton
patent: 3618107 (1971-11-01), Spanos
patent: 3641578 (1972-02-01), Spanos et al.
patent: 3681772 (1972-08-01), Ingerson
patent: 3686674 (1972-08-01), Clasby et al.
patent: 3745585 (1973-07-01), Barbano
patent: 3825933 (1974-07-01), Debski et al.
patent: 3919710 (1975-11-01), Fletcher et al.
patent: 3987456 (1976-10-01), Gelin
patent: 4243993 (1981-01-01), Lamberty et al.
Grekou et al, "Plane Equiangular 4-Arm Spiral Antenna with Conical Reflector", Electronics Letters, 1-23-75, vol. 11, No. 2, pp. 38-40.
Grekou et al, "Plane Equiangular 4-Arm Spiral Antenna with Conical Reflector and Cavity, Fitted into a Structure", Electronics Letters, 1975.
Atia, "Analysis of Multiple-Arm Conical Log-Spiral Antennas", IEEE Trans. on Antennas and Prop., May 1971, pp. 320-331.
Blakney Thomas L.
Connell Douglas D.
Lamberty Bernard J.
Lee James R.
Lieberman Eli
The Boeing Company
Wimer Michael C.
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