FOLDABLE ANTENNA FOR RECONFIGURABLE RADAR SYSTEM

• US 20090267835A1
• Filed: 04/25/2008
• Published: 10/29/2009
• Est. Priority Date: 04/25/2008
• Status: Active Grant

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Tietjen, Byron W.
• Granted Patent: US 8,446,326 B2
• Time in Patent Office: Days
• US Class Current: 342/368
• CPC Class Codes: H01Q 1/084 Pivotable antennas
• CPC Class Codes: H01Q 1/3233 particular used as part of a sensor or in a security system, e.g. for automotive radar, navigation systems
• CPC Class Codes: H01Q 3/02 using mechanical movement of antenna or antenna system as a whole
• CPC Class Codes: H01Q 9/12 adapted for adjustment of angle between elements

Abstract

The invention provides for phased array radar system that mechanically reconfigures its antenna array from a single faced aperture into two geometrically opposed arrays.

Claims

1. A reconfigurable phased array radar system, comprising:

a given plurality of antenna radiating elements positioned on a foldable frame in a main array, said main array having a given aperture when said frame is positioned in a single plane,

an assembly positioned on said frame to mechanically fold and separate said frame into first and second frame portions wherein said plurality of antenna elements are separated into first and second pluralities mechanically positioned on said first and second frame portions defining back-to-back arrays, wherein said first frame portion provides a first aperture less than said given aperture to enable antenna radiation in a first direction and said second frame portion provides a second aperture also less than said given aperture to enable radiation in a second direction.

2. The reconfigurable phased array radar system according to claim 1, wherein,

said first and second pluralities of antenna elements are equal in number with each plurality being one half of said given plurality, with said first and second apertures being one-half of said given aperture.

3. The reconfigurable phased array radar system according to claim 1, wherein said assembly comprises a hinge member positioned centrally on said frame to fold said frame into an inverted “

V”

shape, wherein said first and second apertures face opposite directions.

4. The reconfigurable phased array radar system according to claim 3, further including means coupled to said frame to lock said frame in said folded position.

5. The reconfigurable phased array radar system according to claim 1, wherein said first and second pluralities of antenna elements are unequal in number, providing first and second unequal antenna apertures.

6. The reconfigurable phased array radar system according to claim 1, wherein said first and second apertures are coupled to electronic means for independently steering said sub-apertures.

7. The reconfigurable phased array radar system according to claim 1, further comprising a rotating assembly coupled to said frame for rotating said foldable frame.

8. The reconfigurable phased array radar system according to claim 1, wherein said back-to-back arrays are adapted for short range target detection.

9. The reconfigurable phased array radar system according to claim 1, wherein said main array is adapted for long range target detection.

10. A reconfigurable phased array radar system comprising:

a latchably secured hinged antenna frame having an assembly for varying the elevation and directional orientation of one or more array apertures contained therein and which apertures are electronically combined and independently steered for detecting one or more targets, said antenna frame operative in a first mode as a single face antenna array aperture, and in a second mode as a dual faced multi-aperture antenna array.

11. The system of claim 10, wherein the at least two apertures are geometrically opposed.

12. The system of claim 10, wherein the system is rotable through 360°

degrees.

13. The system of claim 10, wherein in said second mode, said frame is operated to fold at a hinge when a latch is operated to cause said frame to be positioned in an inverted “

V”

configuration, wherein one array associated with one folded portion of said frame provides an aperture which is one half of said single faced aperture and with said other folded portion providing another aperture which is also one half of said single faced aperture.

14. A method for reconfiguring a phased array radar system, comprising the steps of:

placing a plurality of antenna elements on a frame having a hinge which enables said frame to fold,

positioning said frame in a vertical direction,

energizing said elements to cause said array to emit a radiation pattern for tracking long range targets, said vertical antenna array being a full aperture array,

folding said frame about said hinge to cause said frame to assume an inverted “

V”

configuration with a first plurality of said elements located on a first folded frame portion and a second plurality of elements located on a second folded frame portion,

energizing said first and second plurality of elements to cause said elements to emit at least a radiation pattern from said first folded portion and a second radiation pattern from said second folded portion for tracking short range targets.

15. The method according to claim 14, further including the step of placing said hinge on said frame relatively at the center of said frame to separate said frame into relatively equal first and second portions, each portion having the same number of antenna elements to thereby provide two geometrically opposed arrays, each of which is one half the full array aperture.

16. A reconfigurable phased array antenna system comprising:

a foldable frame having positioned thereon a plurality of radiating elements which when energized when said frame is not folded provide a radiation pattern with said radiating elements forming a single face aperture antenna,

means coupled to said frame to reconfigure said array from a single face aperture into two geometrically opposed arrays, each array having a smaller aperture than said single face aperture.

17. The reconfigurable phased array radar system according to claim 16, wherein said means includes a fold line positioned near the center of said frame to separate said frame into a first and a second portion, a hinge joining said first and second portions at said fold line to enable said frame to assume a generally inverted “

V”

configuration.

18. The array according to claim 16, further including means coupled to said frame for rotating the same about a vertical axis.

19. A reconfigurable antenna comprising:

a base;

a radar array having a single faced aperture and a mechanical assembly coupled to said array to reconfigure said array into two geometrically opposed arrays.

20. The reconfigurable phased array radar system according to claim 19, wherein each geometrically opposed array has an aperture which is one half said single faced aperture in size.