Active array lens antenna using CTS space feed for reduced antenna depth

• US 6,421,021 B1
• Filed: 04/17/2001
• Issued: 07/16/2002
• Est. Priority Date: 04/17/2001
• Status: Expired due to Term

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Fitzgerald, Patrick J., Buczek, Steven G., Rupp, Frederick C., Quan, Clifton
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): NGUYEN, HOANG V
• Application Number:
  US09/836,896
• Time in Patent Office: 455 Days
• Field of Search: 343/753, 343/754, 343/770, 343/771, 343/772, 343/776, 343/909
• US Class Current: 343/753
• CPC Class Codes: H01Q 13/085 Slot-line radiating ends
• CPC Class Codes: H01Q 21/0018 Space- fed arrays
• CPC Class Codes: H01Q 21/0025 Modular arrays
• CPC Class Codes: H01Q 21/064 using horn or slot aerials slotted waveguides arrays H01Q21/005

Abstract

A space-fed active array lens antenna system has an active array lens with a first array of radiating elements defining a front antenna aperture which transmits and receives RF energy from free space, a second array of radiating elements defining a rear antenna aperture which transmits and receives RF energy from a feed aperture, and an array of transmit/receive (T/R) modules sandwiched between the front aperture and rear aperture. The T/R modules include a phase control circuit and an amplitude control circuit which provide phase and amplitude control for RF signals passing through the modules. The feed aperture includes a wide band CTS aperture which produces a plane wave in the near field.

Claims

1. A space-fed active array lens antenna system, comprising:

an active array lens comprising a first array of radiating elements defining a front antenna aperture which transmits and receives RF energy to and from free space, a second array of radiating elements defining a rear antenna aperture which transmits and receives RF energy to and from a feed aperture, and an array of transmit/receive (T/R) modules coupled between the front aperture and rear apertures;

wherein the T/R modules include a phase control circuit and an amplitude control circuit which provide phase and amplitude control for RF signals passing between the front aperture and the rear aperture; and

wherein the feed aperture comprises a continuous transverse stub (CTS) aperture which produces a plane wave in the near field.

2. The system of claim 1, wherein the array has a frequency range of operation of between 6 Ghz and 18 Ghz.

3. The system of claim 1, wherein the first array of radiating elements is an array of flared notch radiating elements.

4. The system of claim 3, wherein the second array of radiating elements is an array of flared notch radiating elements.

5. The system of claim 4 wherein the radiating elements are arranged in rows and columns, and wherein the radiating elements for a group of radiating elements of the first array and the second array in a column are fabricated on a single printed circuit board.

6. The system of claim 1 wherein the second array of said radiating elements is positioned in the near field of the feed aperture.

7. The system of claim 1 wherein the CTS aperture is a wide band aperture capable of operation over a wide frequency band without significant scanning of a beam in near field over the frequency band of operation.

8. The system of claim 7 wherein the CTS aperture includes a feed architecture comprising a corporate parallel plate feed structure.

9. The system of claim 7 wherein the second array of said radiating elements is positioned in the near field of the feed aperture, at a gap spacing of less than one inch, and wherein the wide band aperture is for operation over a frequency range of 6 Ghz to 18 Ghz.

10. The system of claim 1 wherein the CTS aperture comprises a plurality of spaced continuous stub radiating elements, and wherein a spacing of the radiating elements of the second array does not match a spacing of the continuous stub radiating elements.

11. The system of claim 1 wherein the feeding of RF signals between the second array of radiating elements and the feed aperture is free of hard electrical interconnects.

12. The system of claim 1 wherein the CTS aperture is a wide band aperture capable of operation over a wide frequency band without significant scanning of a beam in near field over the frequency band of operation.

13. A space-fed active array lens antenna system, comprising:

a wide band feed continuous transverse stub (CTS) feed aperture which produces a plane wave in the near field; and

an active array lens comprising;

a first array of radiating elements defining a front antenna aperture which transmits and receives RF energy to and from free space,

a second array of radiating elements defining a rear antenna aperture which transmits and receives RF energy to and from said feed aperture, the second array positioned in the near field of the feed aperture, and

an array of transmit/receive (T/R) modules coupled between the front aperture and rear aperture, said T/R modules including a phase control circuit and an amplitude control circuit which provide phase and amplitude control for RF signals passing between the front aperture and the rear aperture.

14. The system of claim 13, wherein the first array of radiating elements is an array of flared notch radiating elements.

15. The system of claim 14, wherein the second array of radiating elements is an array of flared notch radiating elements.

16. The system of claim 15 wherein the radiating elements are arranged in rows and columns, and wherein the radiating elements for a group of radiating elements of the first array and the second array in a column are fabricated on a single printed circuit board.

17. The system of claim 13 wherein the CTS aperture includes a feed architecture comprising a corporate parallel plate feed structure.

18. The system of claim 13 wherein the second array of said radiating elements is positioned at a gap spacing of less than one inch from the CTS aperture, and wherein the wide band aperture is for operation over a frequency range of 6 Ghz to 18 Ghz.

19. The system of claim 13 wherein the CTS aperture comprises a plurality of spaced continuous stub radiating elements, and wherein a spacing of the radiating elements of the second array does not match a spacing of the continuous stub radiating elements.

20. The system of claim 13 wherein the feeding of RF signals between the second array of radiating elements and the feed aperture is free of hard electrical interconnects.