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Publication numberUS3221333 A
Publication typeGrant
Publication dateNov 30, 1965
Filing dateMar 5, 1962
Priority dateMar 5, 1962
Publication numberUS 3221333 A, US 3221333A, US-A-3221333, US3221333 A, US3221333A
InventorsMacartney Brown Desmond
Original AssigneeUltra Electronics Ltd
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Inflatable bag aerial
US 3221333 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

Nov. 30, 1965 D. M. BROWN 3,221,333


United States Patent "ice 3,221,333 INFLATABLE BAG AERIAL Desmond Macartney Brown, Hounslow, Middlesex, England, assignor to Ultra Electronics Limited, London, England, a corporation of Great Britain Filed Mar. 5, 1962, Ser. No. 177,529 1 Claim. (Cl. 343-872) This invention relates to an inflatable bag aerial which may be rolled or folded when not in use, such as may be used, for example, in a parachute pack for a crash position indicator radio beacon, in meteorological balloons, and in the radio kit of a man engaged in active service.

In accordance with the invention, a radio aerial is provided that comprises two webs of wire so supported by a flexible bag that when the bag is inflated, the two webs of wire lie in substantially parallel spaced apart planes to provide a tuned radio aerial operating on the capacity plate principle. Each web of wire may be directly secured, as by sewing, to a flexible sheet of nonelectrically conductive material. The two sheets may be secured to the interior of the inflatable bag, or they may form part of the exterior walls of the inflatable bag.

The following description relates to the accompanying drawings and showing by way of example only two embodiments of the invention.

In the drawings:

FIGURE 1 is a view of one web of wire supported on a flexibble sheet of nonelectrically conductive material;

FIGURE 2 is a section through an inflated bag and showing the two webs of wire therein in a parallel spaced apart condition, each web being on a sheet of nonelectrically conductive material; and

FIGURE 3 is a section through an inflated bag, of which the walls themselves carry the two webs of wire in a parallel spaced apart condition.

As shown in FIGURE 1, a circular sheet 11 of plastic material has an aerial in the form of a framework of wire 12 sewn upon one surface. The wire used for the web 12 may be of the type used for telephone headset cable. All joints and crossings of the web or frame- 3,221,333 Patented Nov. 30, 1965 work of wire are soldered together. at its centre 13.

As shown in FIGURE 2, the circular sheets 11 are secured to the interior of an inflatable bag 14. As shown, there are two such sheets 11, each with its aerial web 12, so that the two webs together co-operate to form the well-known capacity plate aerial. Being inflated as shown, the bag 14 has the shape of an oblate spheroid.

In FIGURE 3, on the other hand, two circular sheets 11 of nonelectrically conductive material are used to form two parallel spaced apart and opposite 'faces of an inflatable bag 15, each sheet 11 carrying an aerial web.

The dimensions of the webs 12 and the spacing between the two webs, is, of course, determined by the desired operating frequency. It has been shown that for a reasonable size of aerial, the invention has been most useful over a band of frequency of mc./s. to 400 mc./s.

What is claimed is:

A radio antenna comprising an inflatable flexible bag in the shape of an oblate spheroid when inflated, including when inflated, a pair of spaced parallel insulating planar surfaces connected to a medial portion of said spheroid; a first conductive antenna element mounted on one of said planar surfaces and a second conductive antenna element mounted on the other of said planar surfaces, said elements being mounted in opposing relation in such a manner as to define a capacitive plate antenna when said bag is inflated.

The aerial is fed References Cited by the Examiner UNITED STATES PATENTS 2,814,038 11/ 1957 Miller 343-872 2,888,675 5/1959 Pratt et al 343-880 2,996,212 8/1961 OSullivan 343-18 3,047,860 7/19612 Swallow et al 343-915 3,056,131 9/ 1962 McCreary 343-872 3,138,798 6/1964 Greenwood 343-18 FOREIGN PATENTS 758,090 9/ 1956 Great Britain.


Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2814038 *Jul 29, 1953Nov 19, 1957Westinghouse Electric CorpLightweight antennas
US2888675 *Feb 7, 1956May 26, 1959Martin CoWater borne inflatable radar reflector unit
US2996212 *Aug 20, 1959Aug 15, 1961Jr William John O'sullivanSelf supporting space vehicle
US3047860 *Nov 27, 1957Jul 31, 1962Swallow Austin BTwo ply electromagnetic energy reflecting fabric
US3056131 *Oct 1, 1956Sep 25, 1962Collins Radio CoInflatable antenna
US3138798 *Jul 18, 1957Jun 23, 1964Anderson Greenwood & CoOpposed corner radar reflector assembly
GB758090A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3413645 *Apr 7, 1966Nov 26, 1968Navy UsaElongated inflatable parabolic antenna
US3546706 *Oct 31, 1966Dec 8, 1970Hughes Aircraft CoLightweight reflecting structures utilizing electrostatic inflation
US4901081 *Aug 22, 1988Feb 13, 1990Lifeball International CorporationElliptical inflatable radar reflector
US6897832May 30, 2002May 24, 2005John R. Essig, Jr.Inflatable multi-function parabolic reflector apparatus and methods of manufacture
US7365703 *Feb 16, 2006Apr 29, 2008Saab AbRadar reflector
US7382332Dec 4, 2003Jun 3, 2008Essig Jr John RaymondModular inflatable multifunction field-deployable apparatus and methods of manufacture
US20030020667 *May 30, 2002Jan 30, 2003Essig John R.Inflatable multi-function parabolic reflector apparatus and methods of manufacture
US20040207566 *Dec 4, 2003Oct 21, 2004Essig John RaymondModular inflatable multifunction field-deployable apparatus and methods of manufacture
US20050103329 *Nov 30, 2004May 19, 2005Essig John R.Jr.Inflatable multi-function parabolic reflector apparatus and methods of manufacture
US20060187110 *Feb 16, 2006Aug 24, 2006Saab AbRadar reflector
US20100108057 *Aug 26, 2009May 6, 2010Coolearth SolarInflatable solar concentrator balloon method and apparatus
WO2002097917A1 *May 30, 2002Dec 5, 2002Essig John R JrInflatable multi-function parabolic reflector apparatus and methods of manufacture
U.S. Classification343/872, 343/915, 343/881
International ClassificationH01Q1/08
Cooperative ClassificationH01Q1/082
European ClassificationH01Q1/08B1