Reflect array antennas having monolithic sub-arrays with improved DC bias current paths

• US 20070090997A1
• Filed: 10/20/2005
• Published: 04/26/2007
• Est. Priority Date: 10/20/2005
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Brown, Andrew, Brown, Kenneth, Jones, George, Dolash, William
• Granted Patent: US 7,423,601 B2
• Time in Patent Office: Days
• US Class Current: 343/700.0MS
• CPC Class Codes: H01Q 21/0018 Space- fed arrays
• CPC Class Codes: H01Q 21/0093 Monolithic arrays
• CPC Class Codes: H01Q 21/061 Two dimensional planar arrays
• CPC Class Codes: H01Q 3/46 Active lenses or reflecting arrays

Abstract

Embodiments of active array antennas are generally described herein. Other embodiments may be described and claimed. In some embodiments, a reflect array antenna includes an array of rectangular monolithic sub-array modules arranged in a non-uniform pattern to leave a plurality of rectangular gaps in the pattern. A DC feed pin located within each gap may provide DC bias current to the sub-array modules. The sub-array modules may be mounted on a heat sink in the non-uniform pattern. The heat sink may have holes aligned with the gaps to allow passage of the DC feed pins. In some embodiments, an array cooling assembly may be coupled to the back of the heat sink to cool the reflect array antenna with a coolant.

Claims

1. A reflect array antenna comprising:

an array of rectangular monolithic sub-array modules arranged in a non-uniform pattern to leave a plurality of rectangular gaps in the pattern, the gaps being smaller in size than a size of the sub-array modules; and

a DC feed pin located within each gap to provide DC bias current to the sub-array modules.

2. The reflect array antenna of claim 1 further comprising a heat sink, wherein the sub-array modules are mounted on the heat sink in the non-uniform pattern, and

wherein the heat sink has holes aligned with the gaps to allow passage of the DC feed pins.

3. The reflect array antenna of claim 2 wherein the heat sink has a substantially paraboloidal surface, and

wherein the sub-array modules are mounted on the substantially paraboloidal surface in the non-uniform pattern.

4. The reflect array antenna of claim 2 wherein each sub-array module comprises a number of sub-array elements,

wherein the sub-array modules include a bias grid separating the sub-array elements, the DC bias grid to receive the DC bias current from the DC feed pins, and

wherein the reflect array antenna further comprises a plurality DC feed lines coupling each of the DC feed pins to the bias grids of the sub-array elements adjacent to the gaps.

5. The reflect array antenna of claim 4 wherein the sub-array elements include an amplifier element that receives some of the DC bias current that is supplied at a bias voltage between two and three volts.

6. The reflect array antenna of claim 4 further comprising wire bonds coupling the bias grids of adjacent sub-array modules.

7. The reflect array antenna of claim 4 wherein the DC feed pin within each gap is a first DC feed pin to provide drain current to amplifier elements of the sub-array modules, and

wherein the reflect array antenna further comprises a second feed pin within each gap, the second feed pin to provide gate current to amplifier elements of the sub-array modules.

8. The reflect array antenna of claim 4 wherein each sub-array element comprises:

a receive antenna to receive a spatially-fed radio-frequency (RF) input signal;

an amplifier element to amplify the received RF input signal; and

a transmit antenna to transmit an amplified version of the RF input signal.

9. The reflect array antenna of claim 8 wherein the RF input signal is a W-band signal, and

wherein the receive antenna and transmit antennas have orthogonal polarizations.

10. The reflect array antenna of claim 8 wherein each sub-array module comprises a single monolithic substrate,

wherein the sub-array elements of each sub-array module are fabricated on the single monolithic substrate,

wherein the receive antennas and the transmit antennas are cavity-backed antennas, and

wherein the single integrated substrate includes cavities adjacent to the receive and transmit antennas.

11. The reflect array antenna of claim 2 further comprising an array cooling assembly coupled to the heat sink to cool the reflect array antenna,

wherein the array cooling assembly has holes aligned with the gaps to allow passage of the DC feed pins, and

wherein the array cooling assembly is cooled by a coolant that flows through the array cooling assembly.

12. The reflect array of claim 11 wherein the coolant is a phase-change fluid.

13. The reflect array antenna of claim 11 further comprising a bias current layer to provide the DC bias current to the sub-array modules,

wherein the array cooling assembly is located between the heat sink and the bias current layer.

14. The reflect array antenna of claim 13 further comprising a temperature sensor to monitor a temperature of the reflect array antenna,

wherein at least one of pressure and flow-rate of the coolant is controlled based on the monitored temperature.

15. The reflect array antenna of claim 1 wherein the sub-array modules are substantially square and wherein the gaps are substantially square,

wherein the sub-array modules has exactly a perfect square number of active array elements, and

wherein an area of each of the gaps in the pattern is substantially a square area equal to approximately a perfect square number of active array elements that is lower than the perfect square number of active array elements of each sub-array module.

16. The reflect array antenna of claim 15 wherein the perfect square number of active array elements of each sub-array module comprises one of either 4, 9, 16, 25, 36, 49.

17. The reflect array antenna of claim 16 wherein each sub-array module comprises nine active array elements, and

wherein the area of the gap is approximately equal to an area of either one or four of the active array elements.

18. The reflect array of claim 17 wherein the pattern includes one gap for approximately every twelve sub-array modules.

19. The reflect array of claim 17 wherein the pattern includes one gap for approximately every twenty-four sub-array modules.

20. A reflect array antenna comprising:

an array of groups of monolithic sub-array modules, each group adhered to a circuit board,

wherein each circuit board includes DC bias current bonding pads along at least one of its edges, and

wherein the outer sub-array modules of a group receive DC bias current directly from the bonding pads.

21. The reflect array antenna of claim 20 wherein bond wires couple the bonding pads to bias grids of the monolithic sub-array modules along a perimeter of the circuit board.

22. The reflect array antenna of claim 21 wherein additional wire bonds convey the DC bias current among one or more adjacent sub-array modules within each group.

23. The reflect array of claim 21 wherein each monolithic sub-array module comprises a number of sub-array elements, and

wherein the monolithic sub-array modules include the bias grid separating the sub-array elements,

wherein the bias grid receives the DC bias current from the bonding pads.

24. The reflect array of claim 21 further comprising a heat sink,

wherein the groups of the array are arranged in a substantially uniform pattern without gaps in the pattern, and

wherein the circuit board associated with each group is adhered to the heat sink.

25. The reflect array antenna of claim 21 wherein the monolithic sub-array modules are substantially square in shape, and

wherein the circuit boards that include the groups of monolithic sub-array modules are substantially square in shape.

26. The reflect array antenna of claim 21 wherein each group has exactly a perfect square number of monolithic sub-array modules, and

wherein each monolithic sub-array module has exactly a perfect square number of sub-array elements.

27. The reflect array antenna of claim 26 wherein the perfect square number of monolithic sub-array modules of each group comprises one of either 4, 9, 16, 25, 36,49, and

wherein the perfect square number of array elements of each monolithic sub-array module comprises one of 4, 9, 16, 25, 36, 49.

28. The reflect array antenna of claim 23 wherein each sub-array element comprises:

a receive antenna to receive a spatially-fed radio-frequency (RF) input signal;

an amplifier element to amplify the received RF input signal; and

a transmit antenna to transmit an amplified version of the RF input signal.

29. The reflect array antenna of claim 28 wherein the RF input signal is a W-band signal,

wherein the receive antenna and transmit antennas have orthogonal polarizations.

30. The reflect array antenna of claim 28 wherein each sub-array module comprises a single monolithic substrate,

wherein the sub-array elements of each sub-array module are also fabricated on the single monolithic substrate,

wherein the receive antennas and the transmit antennas are cavity-backed antennas, and

wherein the single integrated substrate includes cavities adjacent to the receive and transmit antennas.

31. The reflect array antenna of claim 30 wherein the circuit board further includes cavities aligned with the receive and transmit antennas of the sub-array elements, the cavities of the circuit board being portions on the circuit board without ground conductive material.

32. The reflect array antenna of claim 24 further comprising an array cooling assembly coupled to the heat sink to cool the reflect array antenna,

wherein the array cooling assembly is cooled by a coolant that flows through the array cooling assembly.

33. The reflect array antenna of claim 32 further comprising a bias current layer to provide the DC bias current to the groups,

wherein the array cooling assembly is located between the heat sink and the bias current layer.

34. The reflect array antenna of claim 33 further comprising a temperature sensor to monitor a temperature of the reflect array antenna,

wherein at least one of pressure and flow-rate of the coolant is controlled based on the monitored temperature.

35. A reflect array antenna comprising;

a plurality of active sub-array elements arranged in a uniform pattern on a circuit board,

wherein the circuit board includes a plurality of DC bias feeds through the circuit board to couple with bias pads of the sub-array elements.

36. The reflect array antenna of claim 35 wherein a plurality of the active sub-array elements are fabricated on a single monolithic substrate to comprise a sub-array module, wherein the active array antenna comprises a plurality of the sub-array modules,

wherein the reflect array antenna comprises a plurality of the circuit boards are arranged in a uniform pattern, and

wherein a group of the sub-array modules are adhered to each circuit board.

37. The reflect array antenna of claim 36 wherein the plurality of circuit boards are arranged in a uniform pattern on a heat sink, and

wherein the circuit boards further comprise thermal vias to thermally couple the sub-array elements with the heat sink.

38. The reflect array antenna of claim 37 wherein the DC bias feeds include a drain bias feed and a gate bias feed for each active sub-array element, the drain bias feeds and gate bias feed being provided through the circuit board,

wherein each active sub-array element includes a drain bias pad to couple with the drain bias feed of the circuit board, and

wherein each active sub-array element includes a gate bias pad to couple with the gate bias feed of the circuit board.

39. The reflect array antenna of claim 35 wherein each sub-array element comprises a receive antenna, an amplifier element, and a transmit antenna, and

wherein the circuit board includes cavities aligned with receive and transmit antennas of the active sub-array elements.

40. The reflect array antenna of claim 39 wherein the receive antenna, amplifier and transmit antenna receive and re-transmit a spatially fed W-band RF input signal, and

wherein the receive antenna and transmit antennas have orthogonal polarizations.

41. A millimeter wave deterring device comprising:

an active reflect array antenna; and

a W-band RF source to generate a substantially spherical wavefront for incident on the active reflect array antenna, the active reflect array antenna to amplify the incident wavefront and generate a high-power wavefront, the high-power wavefront is to produce a deterring effect on a target,

wherein the active reflect array antenna comprises;

an array of rectangular monolithic sub-array modules arranged in a non-uniform pattern to leave a plurality of rectangular gaps in the pattern, the gaps being smaller in size than a size of the sub-array modules; and

a DC feed pin located within each gap to provide DC bias current to the sub-array modules.

42. The weapon of claim 41 further comprising a heat sink, wherein the sub-array modules are mounted on the heat sink in the non-uniform pattern, and

wherein the heat sink has holes aligned with the gaps to allow passage of the DC feed pins.

43. The weapon of claim 42 wherein the heat sink has a substantially paraboloidal surface, and

wherein the sub-array modules are mounted on the substantially paraboloidal surface in the non-uniform pattern to generate either a collimated or converging wavefront.

44. The weapon of claim 42 wherein each sub-array module comprises a number of sub-array elements,

wherein the sub-array modules include a bias grid separating the sub-array elements, the DC bias grid to receive the DC bias current from the DC feed pins, and

wherein the reflect array antenna further comprises a plurality DC feed lines coupling each of the DC feed pins to the bias grids of the sub-array elements adjacent to the gaps.

45. The weapon of claim 44 wherein each sub-array element comprises:

a receive antenna to receive a spatially-fed radio-frequency (RF) input signal;

an amplifier element to amplify the received RF input signal; and

a transmit antenna to transmit an amplified version of the RF input signal.

46. The weapon of claim 45 wherein the RF input signal is a W-band signal.

47. The weapon of claim 45 w wherein the receive antenna and transmit antennas have orthogonal polarizations.

48. The weapon of claim 45 wherein each sub-array module comprises a single monolithic substrate, and

wherein the sub-array elements of each sub-array module are fabricated on the single monolithic substrate.

49. The weapon of claim 45 wherein the RF input signal is a W-band signal.

50. The weapon of claim 45 wherein the receive antennas and the transmit antennas are cavity-backed antennas, and

wherein the single integrated substrate includes cavities adjacent to the receive and transmit antennas.

51. The weapon of claim 42 further comprising an array cooling assembly coupled to the heat sink to cool the reflect array antenna,

wherein the array cooling assembly has holes aligned with the gaps to allow passage of the DC feed pins, and

wherein the array cooling assembly is cooled by a coolant that flows through the array cooling assembly.