Continuous transverse stub element device antenna array configurations

• US 5,412,394 A
• Filed: 08/10/1993
• Issued: 05/02/1995
• Est. Priority Date: 08/29/1991
• Status: Expired due to Term

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Hughes Aircraft Company (Rtx Corporation)
• Inventors: Milroy, William W.
• Primary Examiner(s): Hajec, Donald
• Assistant Examiner(s): Ho, Tan
• Application Number:
  US08/104,467
• Time in Patent Office: 630 Days
• Field of Search: 343/771, 343/772, 343/767, 343/770, 343/785, 343/786, 29/600, 333/237, 333/239, 333/248
• US Class Current: 343/785
• CPC Class Codes: H01Q 13/20 Non-resonant leaky-waveguide or transmission-line antennas; Equivalent structures causing radiation along the transmission path of a guided wave
• CPC Class Codes: H01Q 13/28 comprising elements constituting electric discontinuities and spaced in direction of wave propagation, e.g. dielectric elements or conductive elements forming artificial dielectric

Abstract

A dielectric material is formed into a structure having two parallel broad surfaces with one or more raised integral portions extending transversely across at least one of the broad surfaces. The exterior is uniformly conductively coated resulting in a parallel plate waveguide having a continuous transverse stub element disposed adjacent one plate thereof. Purely reactive elements are formed by leaving the conductive coating on the terminus of the stub element, or by narrowing the terminus of the stub element. Radiating elements are formed when stub elements of moderate height are opened to free space. Radiating, coupling and/or reactive continuous transverse stub elements may be combined in a common parallel plate structure in order to form a variety of microwave, millimeter wave and quasi-optical components including integrated filters, couplers and antenna arrays. Fabrication of the dielectrically-loaded continuous transverse stub element can be efficiently accomplished by machining, extruding or molding the dielectric structure, followed by uniform conductive plating in order to form the parallel plate transmission line. In the case of antenna applications, machining or grinding is performed on the stub terminus to expose the dielectric material at the end of the stub element.

Claims

1. A shaped-beam antenna array employing continuous transverse stubs as radiating elements comprising:

a planar sheet of dielectric material having two generally parallel broad surfaces separated by a predetermined distance and having a plurality of elongated, raised, relatively thin, rectangular dielectric members formed along a broad surface of the sheet of dielectric material that extend across one dimension of the broad surface and that extend away from the broad surface, and wherein the plurality of thin rectangular dielectric members are spaced apart from each other by a predetermined distance and wherein the rectangular dielectric members vary in length; and

a conductive material disposed on the broad surfaces of the sheet of dielectric material and on transversely extending edgewalls formed by the plurality of thin rectangular dielecteric members so as to define a parallel plate waveguide having a plurality of continuous variable length transverse stubs disposed on one plate thereof, and wherein distal ends of the plurality of thin rectangular dielectric members are free of the conductive material so as to define a plurality of radiating elements, and wherein an edge of the sheet of dielectric material is free of conductive coating so as to define a feed for the shaped-beam antenna array,

whereby precise control of individual phase elements result from the variable length transverse stubs.

2. The squinted-beam antenna array of claim 1 wherein line-feed phase velocity variation with respect to the antenna array is used to scan the squinted-beam antenna array.

3. The squinted-beam antenna array of claim 1 wherein parallel plate phase velocity variation is used to scan the squinted-beam antenna array.

4. The squinted-beam antenna array of claim 1 wherein parallel plate phase velocity variation is used to tune the squinted-beam antenna array.

5. The squinted-beam antenna array of claim 1 wherein scanning by frequency is used to scan the squinted-beam antenna array.

6. A squinted-beam antenna array employing continuous transverse stubs as radiating elements comprising:

a planar sheet of dielectric material having two generally parallel broad surfaces separated by a predetermined distance and having a plurality of elongated, raised, relatively thin, rectangular dielectric members formed along a broad surface of the sheet of dielectric material that extend across one dimension of the broad surface and that extend away from the broad surface, and wherein the plurality of thin rectangular dielectric members are spaced apart from each other in a predetermined selection of spacing; and

a conductive material disposed on the broad surfaces of the sheet of constituent material dielectric constant and on transversely extending edgewalls formed by the plurality of thin rectangular dielectric members so as to define a parallel plate waveguide having a plurality of continuous transerse stubs disposed on one plate thereof, and wherein distal ends of the plurality of thin rectangular dielectric members are free of the conductive material so as to define a plurality of radiating elements, and wherein an edge of the sheet of dielectric material is free of conductive coating so as to define a feed for the squinted-beam antenna array, whereby a predetermined beam squint is realized.

7. A conformal antenna array employing continuous transverse stubs as radiating elements comprising:

a planar sheet of dielectric material having two generally parallel broad surfaces separated by a predetermined distance and having a plurality of elongated, raised, relatively thin, rectangular dielectric members formed along a broad surface of the sheet of dielectric material that extend across one dimension of the broad surface and that extend away from the broad surface, and wherein the plurality of thin rectangular dielectric members are spaced apart from each other by a predetermined distance and inter-member troughs are formed between each of the members of the plurality of thin rectangular dielectric members; and

a conductive material disposed on the broad surfaces to the sheet of dielectric material and on transversely extending edgewalls formed by the plurality of thin rectangular dielectric members so as to define a parallel plate waveguide having a plurality of continous transverse stubs disposed on one plate thereof, and wherein distal ends of the plurality of thin rectangular dielectric members are free of the conductive material so as to define a plurality of radiating elements, and wherein an edge of the sheet of dielectric material is free of conductive coating so as to define a feed for the antenna array,

whereby the inter-member troughs provide a means of suppressing surface wave phenomena.

8. A method of making a continuous transverse stub antenna element which comprises the following steps:

molding a sheet of dielectric material to form an integral dielectric member having two generally parallel broad surfaces and at least one elongated raised relatively thin rectangular dielectric portion extending transversely across one of the broad surfaces;

metalizing the exterior surfaces of the dielectric member to define a parallel plate waveguide having at least one continous transverse stub disposed on one plate thereof; and

trimming from predetermined surfaces of the exterior of the parallel plate waveguide to permit coupling of energy into and out of the antenna element.