BROAD BAND HALF VIVALDI ANTENNAS AND FEED METHODS

• US 20170207546A1
• Filed: 03/31/2017
• Published: 07/20/2017
• Est. Priority Date: 08/10/2011
• Status: Active Application

• Current Assignee: Dirac Solutions Inc., Lawrence Livermore National Security LLC (Government of the United States of America)
• Original Assignee: Lawrence Livermore National Security LLC (Government of the United States of America)
• Inventors: Benzel, David M., Twogood, Richard E.
• Granted Patent: US 10,276,946 B2
• Time in Patent Office: Days
• CPC Class Codes: H01Q 1/48 Earthing means; Earth screens; Counterpoises
• CPC Class Codes: H01Q 13/085 Slot-line radiating ends
• CPC Class Codes: H01Q 15/14 Reflecting surfaces; Equivalent structures electromagnetic shields H01Q1/526
• CPC Class Codes: H01Q 21/064 using horn or slot aerials slotted waveguides arrays H01Q21/005
• CPC Class Codes: H01Q 21/08 the units being spaced along or adjacent to a rectilinear path waveguide fed H01Q21/0037

Abstract

A single Vivaldi antenna plate (half Vivaldi antenna) over a ground plane can be used to achieve a 50-ohm impedance, or two or more single plates over a ground plane to achieve other impedances. Unbalanced 50-ohm transmission lines, e.g., coaxial cables, can be used to directly feed the antenna.

Claims

1. An apparatus, comprising:

a ground plane; and

a first conductive plate supported in a spaced relationship to the ground plane, wherein the first conductive plate and the ground plane do not touch each other at any place, wherein the first conductive plate arid the ground plane have a gap therebetween that is narrowest at a throat and increases along a first curved surface of the first conductive plate to a first distal tip.

2. The apparatus of claim 1, further comprising a second conductive plate supported in a second spaced relationship to the ground plane, wherein the second conductive plate is electrically connected in parallel with the first conductive plate, wherein the second conductive plate is physically connected to the first conductive plate, wherein the second conductive plate and the ground plane do not touch each other at any place, wherein the second conductive plate and the ground plane have the same gap therebetween as between the first conductive plate and the ground plane, wherein the second conductive plate is narrowest at the first throat and increases along a second curved surface of the second conductive plate to a second distal tip.

3. The apparatus of claim 1 further comprising at least one additional conductive plate supported in at least one additional respective spaced relationship to the ground plane, wherein the at least one additional conductive plate is electrically connected in parallel with the first conductive plate, wherein the at least one additional conductive plate is physically connected to the first conductive plate, wherein the at least one additional conductive plate and the ground plane do not touch each other at any place, wherein the at least one additional conductive plate and the ground plane have the same gap therebetween as between the first conductive plate and the ground plane, wherein the at least one additional conductive plate is narrowest at a respective at least one additional throat and increases along a respective at least one additional curved surface of the respective at least one additional conductive plate to a respective at least one additional distal tip.

4. The apparatus of claim 1, further comprising an electrical feed end located at the throat, wherein the apparatus has a 50-ohm impedance and wherein a 50-ohm coaxial cable is fed directly at the feed end.

5. The apparatus of claim 1, wherein the center conductor of the coaxial cable is directly connected to the electrical feed end and wherein the outer conductor of the coaxial cable is connected to the ground plane.

6. The apparatus of claim 1, further comprising a conductive support with a non-conductive base located at the feed end, further comprising a non-conductive support located at the distal end, wherein the non-conductive base isolates the conductive support from the ground plane, wherein the conductive support together with the non-conductive support fixedly place the first conductive plate over the ground plane.

7. The apparatus of claim 1, wherein the first conductive plate is a solid piece of material.

8. The apparatus of claim 1, wherein the first conductive plate comprises a plurality of hole.

9. The apparatus of claim 1, wherein the first conductive plate comprises a wire mesh.

10. The apparatus of claim 3, wherein the first conductive plate and the at least one additional conductive plate are solid, perforated or wire mesh.

11. The apparatus of claim 3, wherein the first conductive plate and the at least one additional conductive plate are joined together at a first common edge and form a first angle of less than 90 degrees therebetween.

12. The apparatus of claim 3. wherein the first conductive plate and the at least one additional conductive plate are spaced and parallel to each other.

13. The apparatus of claim 3, wherein the first conductive plate and the at least one additional conductive plate are flat.

15. The apparatus of claim 1, further comprising director elements positioned in and extending outwardly from the gap.

16. The apparatus of claim 1, further comprising one or more reflector elements positioned behind the throat relative to the distal tip.

17. The apparatus of claim 16, wherein the one or more reflector elements comprises a plurality of parallel wires or a solid plate.

18. The apparatus of claim 16, wherein the one or more reflector elements are selected from a plurality of conductive rods of various lengths, each slightly longer than half the wavelength of a respective frequency of operation of the apparatus.

14. The apparatus of claim wherein the first conductive plate and the at least one additional conductive plate are curved.