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Publication numberUS3787871 A
Publication typeGrant
Publication dateJan 22, 1974
Filing dateMar 3, 1971
Priority dateMar 3, 1971
Publication numberUS 3787871 A, US 3787871A, US-A-3787871, US3787871 A, US3787871A
InventorsReese J
Original AssigneeUs Navy
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Terminator for spiral antenna
US 3787871 A
A spiral antenna wherein its radiating elements terminate in Archimedean spirals.
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Description  (OCR text may contain errors)

United States Patent 1 1 1111 3,787,871

Reese v Jan. 22, 1974 [54] TERMINATOR FOR SPIRAL ANTENNA 3,618,114 11/1971 343/895 2,863,145 12/ 43/895 [75] Inventor: Joe Reese, China Lake, Calif. v

[73] Assignee: The United States of America as 1 represented y h Secretary of the Primary Examiner-Eli Lieberman Navy, Washington, DC Attorney, Agent, or Firm-R. S. Sciascia; Roy Miller; 221 Filed: Mar. 3, 1971 Adams [21] Appl. No.: 121,606

[52] US. Cl. 343/895 57 ABSTRACT [51] Int. Cl. H0111 H36 [58] Field of Search 343/895 A spu'al antenna wherem lts radlatlng elements terml- 5 Referenc'es Cited nate in Archimedean spirals.

UNITED STATES PATENTS l 5/1962 343/895 Claims, 1 Drawing Figure INVENTOR.


TERMINATOR FOR SPIRAL ANTENNA STATEMENT OF GOVERNMENT INTEREST The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

BACKGROUND OF THE INVENTION In order to achieve an equiangular spiral direction finding antenna which is frequency independent and will operate for any polarization, the antenna radiating elements must be so loaded as to simulate an infinite radiating plane. In prior devices loading is accomplished by physically mounting radio frequency resistive material to the radiating surface of the antenna.

The material is often ferrite filled epoxy, machined to close tolerances in an annular shape, and attached to the antenna at its outermost part. Viewed in cross section, the material is seen as attached at the full diameter of the antenna substrate, and sloping away from the surface of the antenna, in a covering relationship, toward its center. That is, the material is a ferrite loaded epoxy washer having a wedge shaped cross section, wherein the thickest portion of the wedge is attached to the antenna substrate at its outer edge and the thinnest portion of the wedge extends toward the center of the antenna in covering relationship to the radiators, in order to provide gradual resistive coupling to the antenna.

As a result, the antennas physical dimension and weight are increased. Its depth is increased by the thickness of the material. Its diameter by the surface outside the radiating area required for mounting the material; and its weight by the weight of the resistive material, which is primarily iron. Additionally, because of the proximity of the material to the radiating surface the antenna frequency band is limited and its sensitivity is reduced.

SUMMARY OF THE INVENTION The present invention is a means for loading the antenna by encircling the radiating elements with a plurality of interlocking spirals, wherein each of the spirals is attached to a radiating element. These spirals are, in general, Archimedean spirals consisting of elements having constant width, and spacing between adjacent element equal to the elements width.

BRIEF DESCRIPTION OF THE DRAWING The FIGURE is a diagrammatical view of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention which is a means for terminating the radiating elements of a spiral antenna is shown in the FIGURE. Although the spiral antenna shown is composed of two radiating elements 10 and 12, the present invention can be used with spiral antennas having any number of radiators.

is equal to the width of arm 16, and the spacing between adjacent arms 14 and 16 is equal to the arm width. By interlocking, arms 14 and 16 couple and provide resistive loading for radiators l0 and 12, which simulates an infinite radiating plane.

The present invention is implemented as follows: at the radius determined by the parameters defining the intended use (frequency range, etc.), the width of radiating elements 10 and 12 are decreased and converted into interlocking Archimedean spirals 14 and 16, wherein the spacing between adjacent arms 14 and 16 equal the arm width. Although the arms may be of any length, approximately four revolutions by each arm provides satisfactory results'for at least some applications.

The spiral antenna and terminating means may be produced by etching copper clad epoxy glass board. The negative used for etching may be a photocopy of a spiral drawing wherein the design is determined by the antennas intended use. In the alternative, as an example, the terminating means may be constructed from wires wound in the preferred spirals and soldered to the ends of radiators 10 and 12.

As mentioned above, the present invention is not limited to the embodiment shown, but may be utilized with spiral antennas having any number of radiating elements.

What is claimed is:

1. An antenna array comprising;

a plurality of interwound spiral radiators, and

radiator termination means having at least a separate spiral member coupled to each said radiator and encircling said plurality of radiators for simulating an infinite radiating plane.

2. The antenna of claim I wherein each said member is an electrically conductive material in the shape of an Archimedean spiral fixedly attached to each said radiator, such that each said radiator has one electrically conductive Archimedean spiral arm attached thereto.

3. The antenna of claim 2 wherein the Archimedean spiral arms interlock such that the spiral arms attached to adjacent radiators are adjacent.

4. The antenna of claim 3 wherein the width of each said spiral arm is equal to the width of the separation between adjacent spiral arms.

5. The antenna of claim 4 wherein said antenna comprises a copper clad epoxy glass board wherein said radiators and said spiral arms are etched.

6. The antenna of claim 4 wherein said antenna comprises a copper clad epoxy glass board wherein said radiators are etched, and electrically conductive wire in the shape of an Archimedean spiral attached to each radiator.

7. The antenna of claim 4 wherein the length of said arms is such that each said arm encircles said radiators four times.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2863145 *Oct 19, 1955Dec 2, 1958Turner Edwin MSpiral slot antenna
US3034121 *Dec 23, 1959May 8, 1962Riblet Henry BBroad band spherical antenna
US3618114 *Dec 16, 1968Nov 2, 1971Univ Ohio State Res FoundConical logarithmic-spiral antenna
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3969732 *Apr 24, 1975Jul 13, 1976Holloway Albert LSpiral antenna circuit
US4012744 *Oct 20, 1975Mar 15, 1977Itek CorporationHelix-loaded spiral antenna
US4243993 *Nov 13, 1979Jan 6, 1981The Boeing CompanyBroadband center-fed spiral antenna
US4287603 *Aug 23, 1979Sep 1, 1981The Bendix CorporationRadiated input mixer
US4559539 *Jul 18, 1983Dec 17, 1985American Electronic Laboratories, Inc.Spiral antenna deformed to receive another antenna
US4605934 *Aug 2, 1984Aug 12, 1986The Boeing CompanyBroad band spiral antenna with tapered arm width modulation
US4823145 *Sep 12, 1986Apr 18, 1989University Patents, Inc.Curved microstrip antennas
US5619218 *Jun 6, 1995Apr 8, 1997Hughes Missile Systems CompanyCommon aperture isolated dual frequency band antenna
US5640170 *Jun 5, 1995Jun 17, 1997Polhemus IncorporatedPosition and orientation measuring system having anti-distortion source configuration
US5712647 *Apr 17, 1996Jan 27, 1998The United States Of America As Represented By The Administrator Of The National Aeronautics And Space AdministrationSpiral microstrip antenna with resistance
US6166708 *Sep 3, 1992Dec 26, 2000Dassault ElectroniqueApparatus perfected arrangement of spiral antennas
US6300918 *Dec 22, 1999Oct 9, 2001Trw Inc.Conformal, low RCS, wideband, phased array antenna for satellite communications applications
USD731349 *Aug 22, 2013Jun 9, 2015Peter J EricksonRing
DE2642013A1 *Sep 17, 1976May 5, 1977Itek CorpAntennenanordnung
DE4032891A1 *Oct 17, 1990May 28, 1998Dassault ElectroniqueSpiralantennenanordnung
DE4032891C2 *Oct 17, 1990Apr 22, 1999Dassault ElectroniqueBreitband-Antennenanordnung
DE4310070A1 *Mar 27, 1993Sep 29, 1994Deutsches KrebsforschHyperthermy applicator
EP0747992A2 *May 17, 1996Dec 11, 1996Hughes Missile Systems CompanyCommon aperture isolated dual frequency band antenna
U.S. Classification343/895
International ClassificationH01Q9/04, H01Q9/27
Cooperative ClassificationH01Q9/27
European ClassificationH01Q9/27