PHASED ARRAY FED LENS ANTENNA

• US 3,755,815 A
• Filed: 12/20/1971
• Issued: 08/28/1973
• Est. Priority Date: 12/20/1971
• Status: Expired due to Term

• Current Assignee: John J. Stangel, Pasquale A. Valentino
• Original Assignee: John J. Stangel, Pasquale A. Valentino
• Inventors: Stangel, John J., Valentino, Pasquale A.
• Primary Examiner(s): Borchelt, Benjamin A.
• Assistant Examiner(s): Buczinski, S. C.
• Application Number:
  US05/209,863
• Time in Patent Office: 617 Days
• Field of Search: 343/1SA,753,754,854,909,911R
• US Class Current: 342/371
• CPC Class Codes: H01Q 25/002 providing at least two patterns of different beamwidth; Variable beamwidth antennas
• CPC Class Codes: H01Q 3/34 by electrical means active lenses or reflecting arrays H01Q3/46
• CPC Class Codes: H01Q 3/44 varying the electric or magnetic characteristics of reflecting, refracting, or diffracting devices associated with the radiating element
• CPC Class Codes: H01Q 3/46 Active lenses or reflecting arrays
• CPC Class Codes: H04Q 3/34 for the second preselection stage

Abstract

A phased array antenna functions as a source of electromagnetic energy directed toward a non-planar lens positioned in the near field of the phased array antenna. The non-planar lens includes a plurality of modules comprised of collector elements, phase shifter elements and radiator elements. Electromagnetic energy radiated from the feed antenna to the plurality of collector elements in the non-planar lens is coupled from the collector elements through the phase shifter elements to the radiating elements. Each phase shifter has a fixed delay which acts upon the electromagnetic energy transmitting through the phase shifter so that the electromagnetic energy radiated by the associated radiating element combines with the radiated energy from the other radiating elements to produce a beam having a modified scan angle relative to the scan angle of the emitted beam from the phased array antenna.

Claims

1. An electronic scanning antenna system comprising a source of electromagnetic energy, array means including elements, said array means being coupled to said source of electromagnetic energy for producing a first beam of electromagnetic energy having a non-planar phase and controllable focal properties, and lens means responsive to said first beam of electromagnetic energy having a non-planar phase and controllable focal properties which implement a phase gradient for producing a directive second beam of electromagnetic energy having a plane wavefront, a variable range of scan and an attendant variable gain.

2. An electronic scanning antenna system as described in claim 1 in which said source of electromagnetic energy includes a radiating feed horn.

3. An electronic scanning antenna system as described in claim 1 in which said array means coupled to said source of electromagnetic energy includes means for producing a converging first beam of electromagnetic energy having a pre-determined non-planar phase, said array means being capable of producing a first beam of electromagnetic energy at a specific gain over a limited range of scan.

4. An electronic scanning antenna system as described in claim 3 in which said lens means includes means for varying said phase gradient whereby said second beam of electromagnetic energy has an increased range of scan over said limited range of scan with an attendant minimum reduction of gain from said specific gain.

5. An electronic scanning antenna system as described in claim 3 in which said lens means has a fixed phase gradient in all directions for transmitting a directive second beam of electromagnetic energy having a plane wavefront and an increased range of scan over said limited range of scan with an attendant minimum reduction in gain from said specific gain of said array means.

6. An electronic scanning antenna system as described in claim 1 in which said array means includes means for producing a diverging first beam of electromagnetic energy having a pre-determined non-planar phase, said array means being capable of producing a first beam of electromagnetic energy at a specific gain over a limited scan range.

7. An electronic scanning antenna system as described in claim 6 in which said lens means includes means for varying said phase gradient to produce a second beam of electromagnetic energy having a plane wavefront and a reduced range of scan with respect to said limited range of scan and an attendant increase in gain over said specific gain.

8. An electronic scanning antenna system as described in claim 6 in which said lens means includes a fixed phase gradient for transmitting a directive second beam of electromagnetic energy having a plane wavefront and a reduced range of scan with respect to said limited range of scan and an increase in gain over said specific gain of said array means.

9. An electronic scanning antenna system as described in claim 1 in which said array means further includes means for providing a convErging first beam in a first direction and means for providing a diverging first beam in a second direction, and said lens means includes means for varying said phase gradient for producing, in response to said converging first beam, a second beam of electromagnetic energy having a plane wavefront directed in said first direction within a first prescribed range of scan with an attendant reduction in gain from said specific gain and means for varying said phase gradient for producing, in response to said diverging first beam, a second beam of electromagnetic energy having a plane wavefront directed in said second direction within a prescribed range of scan with an attendant increase in gain over said specific gain thereby providing an antenna system having a minimum number of elements.

10. An electronic scanning antenna system as described in claim 1 in which said array means includes collector elements for receiving said electromagnetic energy provided by said source of electromagnetic energy, electronically controlled phase shifter elements coupled to said collector elements and radiator elements coupled to said electronically controlled phase shifter elements.

11. An electronic scanning antenna system as described in claim 1 in which said lens means includes collector elements for receiving said first beam of electromagnetic energy, variable phase shifter elements coupled to said collector elements for implementing said phase gradient, and radiator elements coupled to said variable phase shifter elements for transmitting said directive second beam of electromagnetic energy.

12. An electronic scanning antenna system as described in claim 1 in which said lens means includes a lens having a non-planar shape.

13. An electronic scanning antenna system as described in claim 12 in which said lens has a spherical configuration.

14. An electronic scanning antenna system as described in claim 12 in which said lens means includes a lens having a cylindrical configuration.

15. An electronic scanning antenna system as described in claim 1 in which said lens means is portable.

16. An electronic scanning antenna system as described in claim 1 in which said lens means includes a lens of dielectric material having a variable thickness and non-planar shape whereby the focal properties of said lens are controlled in accordance with said variable thickness and non-planar shape.

17. An electronic scanning antenna system as described in claim 16 in which said lens has a geometrical shape which conforms to the nose profile of a high speed vehicle.

18. An electronic scanning antenna system as described in claim 16 in which said lens is fabricated of titanium dioxide.

19. An electronic scanning antenna system as described in claim 1 in which said lens means includes dipole collector elements for receiving said first beam of electromagnetic energy, flexible cables of varying length coupled to said dipole collector elements, and dipole radiator elements coupled to said flexible cables for transmitting said directive second beam of electromagnetic energy.

20. An electronic scanning antenna system as described in claim 1 in which said lens means includes open-ended collector elements for receiving said first beam of electromagnetic energy, dielectrically loaded circular waveguides coupled to said collector elements for imparting different relative phase delays to said first beam, and open-ended radiator elements coupled to said circular waveguides for transmitting said directive second beam having a plane wavefront.