MULTI-BAND ELECTRONICALLY STEERED ANTENNA

• US 20170062928A1
• Filed: 05/09/2016
• Published: 03/02/2017
• Est. Priority Date: 08/25/2015
• Status: Active Grant

• Current Assignee: United States Air Force (Government of the United States of America)
• Original Assignee: Government of The United States As Represented By The U.S. Air Force (Government of the United States of America)
• Inventors: LEGARE, DAVID J.
• Granted Patent: US 10,103,441 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01Q 21/065 Patch antenna array
• CPC Class Codes: H01Q 25/00 Antennas or antenna systems providing at least two radiating patterns arrangements for changing or varying the orientation or the shape of the directional pattern H01Q3/00
• CPC Class Codes: H01Q 3/26 varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture H01Q3/12, H01Q3/22, H01Q3/24 take precedence
• CPC Class Codes: H01Q 3/30 varying the relative phase between the radiating elements of an array H01Q3/2605, H01Q3/2658, H01Q3/2682, H01Q3/44 take precedence
• CPC Class Codes: H01Q 5/30 Arrangements for providing operation on different wavebands
• CPC Class Codes: H01Q 5/357 using a single feed point
• CPC Class Codes: H01Q 9/0442 with particular tuning means
• CPC Class Codes: H01Q 9/0485 Dielectric resonator antennas

Abstract

Antenna system being tunable over multiple frequency bands. One planar surface of the antenna structure has metallic radiating elements of various geometries with selectable electrical interconnections between the radiating elements. An opposite side of the antenna structure has a signal transmission network with signal feedthroughs to selected metallic radiating elements. The signal transmission network also has phase shift inducing means. Depending on the frequency band of operation, metallic radiating elements are appropriately combined through the electrical interconnections to form composite radiating elements with resonant frequencies within the frequency band of operation. Induced phase shifts in the signal paths feeding selected metallic radiating elements cause a net resultant free-space directivity gain.

Claims

1. An antenna structure, comprising

a first surface and an opposing second surface having a substrate disposed therebetween;

a plurality of metallic radiating elements having various geometries and surface areas being disposed on said first surface;

a first plurality of switches selectably interconnecting said plurality of metallic radiating elements;

a radio frequency transmission network having a plurality of transmission paths being selectably interconnected to a radio frequency signal source by a second plurality of switches, all disposed on said second surface; and

fixed transmission paths through said substrate being disposed between predetermined said metallic radiating elements and said transmission paths;

wherein

selectable actuation among said second plurality of switches causes a connection of said radio frequency signal source to selected said predetermined metallic radiating elements; and

wherein

selectable actuation among said first plurality of switches causes a resultant net metallic radiating element surface area having a predetermined resonant frequency.

2. The antenna structure of claim 1, wherein said resonant frequency is within the band of said radio frequency signal.

3. The antenna structure of claim 1, wherein said first surface, said second surface and said substrate are arranged substantially parallel to each other.

4. The antenna structure of claim 1, wherein said substrate is a dielectric material.

5. The antenna structure of claim 1, wherein said first plurality of switches and said second plurality of switches are computer controlled.

6. The antenna structure of claim 1, wherein said radio frequency transmission network further comprises means for causing a relative phase difference between said transmission paths.

7. The antenna structure of claim 6, wherein said means for causing a relative phase difference is computer controlled.

8. The antenna structure of claim 1, wherein said first plurality of switches are microelectromechanical systems (MEMs).

10. The antenna structure of claim 6, wherein said means for causing a relative phase difference are microelectromechanical systems (MEMs).

9. The antenna structure of 1, wherein said second plurality of switches are microelectromechanical systems (MEMs).

11. In an antenna structure having a first surface with a plurality of metallic radiating elements having selectable interconnections therebetween and an opposing second surface having phase shift inducing signal transmission paths with selectable connections to said metallic radiating elements, a method for providing directed aperture gain over multiple frequency bands, comprising the steps of:

selectably connecting said signal paths to predetermined said metallic radiating elements;

selectably interconnecting said metallic radiating elements so as to cause said interconnected metallic radiating elements to resonate within a desired frequency band; and

imparting a phase shift within said signal paths so as to cause the combined effect of said resonant metallic radiating elements to be directed aperture gain.

12. The method of claim 11, wherein said steps of selectably connecting;

selectably interconnecting; and

imparting a phase shift are computer directed.

13. The method of claim 12, wherein said steps of selectably connecting;

selectably interconnecting; and

imparting a phase shift are microelectromechanical systems (MEMs) actuated.

14. An antenna, comprising:

a substantially planar forward surface;

a substantially planar rearward surface;

a substrate layer disposed between said forward and said rearward surfaces;

metallic radiating elements disposed on said forward surface;

electrical signal paths disposed on said rearward surface;

electrical connections between predetermined said metallic radiating elements and predetermined said electrical signal paths;

electrical switches interconnecting said metallic radiating elements to each other;

a computer processor connected to said switches; and

a non-transitory storage medium containing a stored set of electrical switch-actuating computer programming instructions.

15. The antenna of claim 14, further comprising phase shifting means disposed within said predetermined electrical signal paths.

17. The antenna of claim 15, further comprising a connection between said phase shifting means and said computer processor.

16. The antenna of clam 15, wherein said substrate is a dielectric material.