Aligned duplex antennae with high isolation

• US 7,286,096 B2
• Filed: 03/27/2006
• Issued: 10/23/2007
• Est. Priority Date: 03/28/2005
• Status: Expired due to Fees

• Current Assignee: Radiolink Networks Incorporated
• Original Assignee: Radiolink Networks Incorporated
• Inventors: Fortier, John, Jaffer, Aubrey
• Primary Examiner(s): Nguyen; Hoang V.
• Application Number:
  US11/389,871
• Publication Number:
  US 20070057860A1
• Time in Patent Office: 575 Days
• Field of Search: 343/779, 343/781.P, 343/840, 343/912
• US Class Current: 343/779
• CPC Class Codes: H01Q 1/125 Means for positioning
• CPC Class Codes: H01Q 1/521 reducing the coupling between adjacent antennas
• CPC Class Codes: H01Q 1/525 between emitting and receiving antennas
• CPC Class Codes: H01Q 19/13 the primary radiating source being a single radiating element, e.g. a dipole, a slot, a waveguide termination H01Q19/15 takes precedence
• CPC Class Codes: H01Q 19/132 Horn reflector antennas; Off-set feeding
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• 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 25/001 Crossed polarisation dual antennas orthomode horns H01Q13/0258; cross-polarised rear feeds H01Q19/136; orthomode transducers H01P1/161
• CPC Class Codes: H01Q 3/04 for varying one co-ordinate of the orientation

Abstract

Integrating dual antennae into a single rigid assembly guarantees parallel alignment between the antennae and provides higher isolation with lower insertion loss than duplexing methods can achieve through a single antenna. The resulting higher performance at lower cost can benefit two-way communication systems using time division duplexing, frequency division duplexing, or polarization division duplexing; or combinations of these methods.

Claims

1. An antenna unit, comprising:

a substantially rigid metallic body, the body defining a first curved surface and a second curved surface, the first curved surface defining a first focal point, the second curved surface defining a second focal point, the first curved surface defining a first axis along which the first curved surface can transmit a first electromagnetic beam, the second curved surface defining a second axis along which the second curved surface can receive a second electromagnetic beam, the first axis and the second axis being substantially parallel, the first focal point and the second focal point being separated by a separation distance, the separation distance being greater than a distance between the first focal point and any point on the first curved surface;

a first feedhorn disposed proximal to the first focal point; and

a second feedhorn disposed proximal to the second focal point.

2. An antenna unit according to claim 1, the unit including a first piece of metal, the first piece of metal defining the first and second curved surfaces.

3. An antenna unit according to claim 2, the unit including a second piece of metal, the second piece being substantially rigidly attached to the first piece.

4. An antenna unit according to claim 3, the second piece forming a substantially flat backplate.

5. An antenna unit according to claim 3, the first and second feedhorns being attached to the second piece of metal.

6. An antenna unit according to claim 1, further including a first post and a second post, the first feedhorn being attached to the first post, the second feedhorn being attached to the second post.

7. An antenna unit according to claim 1, a straight line connecting the first focal point and the second focal point intersecting at least one of the first and second curved surfaces.

8. An antenna unit according to claim 1, further including a metallic baffle disposed between the first and second focal points.

9. An antenna unit according to claim 1, further including a radome, the radome enclosing the body, the first feedhorn, and the second feedhorn.

10. An antenna unit according to claim 1, the first feedhorn including a first signal launcher and a second signal launcher, the first and second signal launchers being configured to transmit electromagnetic beams characterized by orthogonal polarizations.

11. An antenna unit according to claim 1, the second feedhorn including a first signal receiver and a second signal receiver, the first and second signal receivers being configured to receive electromagnetic beams characterized by orthogonal polarizations.

12. An antenna unit according to claim 1, the first focal point being disposed within the first feedhorn, the second focal point being disposed within the second feedhorn.

13. A radio communication system, including:

(A) an antenna unit, comprising;

(i) a substantially rigid metallic body, the body defining a first curved surface and a second curved surface, the first curved surface defining a first focal point, the second curved surface defining a second focal point, the first curved surface defining a first axis along which the first curved surface can transmit a first electromagnetic beam, the second curved surface defining a second axis along which the second curved surface can receive a second electromagnetic beam, the first axis and the second axis being substantially parallel, the first focal point and the second focal point being separated by a separation distance, the separation distance being greater than a distance between the first focal point and any point on the first curved surface;

(ii) a first feedhorn disposed proximal to the first focal point; and

(iii) a second feedhorn disposed proximal to the second focal point;

(B) a transmitter coupled to the first feedhorn, the transmitter sending a first signal to the first feedhorn, the first feedhorn transmitting in response to the first signal a first feedhorn beam to the first curved surface, the first curved surface transmitting in response to the first feedhorn beam the first electromagnetic beam;

(C) a receiver coupled to the second feedhorn, the second curved surface transmitting in response to the second electromagnetic beam a second feedhorn signal to the second feedhorn, the second feedhorn transmitting in response to the second feedhorn signal a second signal to the receiver, the first and second electromagnetic beams being characterized by substantially the same frequency, the receiver and the transmitter simultaneously receiving the second signal and transmitting the first signal, respectively.

14. A system according to claim 13, the transmitter including an indoor transmitter portion and an outdoor transmitter potion, the receiver including an indoor portion and an outdoor portion, the outdoor portion of the transmitter generating the first signal, the outdoor portion of the receiver receiving the second signal from the second feedhorn.

15. An antenna unit, comprising:

a substantially rigid metallic body, the body defining a first curved surface and a second curved surface, the first curved surface defining a first focal point, the second curved surface defining a second focal point, the first curved surface defining a first axis along which the first curved surface can transmit or receive a first electromagnetic beam, the second curved surface defining a second axis along which the second curved surface can transmit or receive a second electromagnetic beam, the first axis and the second axis being substantially parallel, the first focal point and the second focal point being separated by a separation distance, the separation distance being greater than a distance between the first focal point and any point on the first curved surface;

a first feedhorn disposed proximal to the first focal point; and

a second feedhorn disposed proximal to the second focal point.

16. A radio communication system, including:

(A) a first antenna unit, comprising;

(i) a first substantially rigid metallic body, the first body defining a first curved surface and a second curved surface, the first curved surface defining a first focal point, the second curved surface defining a second focal point, the first curved surface defining a first axis along which the first curved surface can transmit a first transmitted electromagnetic beam, the second curved surface defining a second axis along which the second curved surface can receive an electromagnetic beam, the first axis and the second axis being substantially parallel, the first focal point and the second focal point being separated by a first separation distance, the first separation distance being greater than a distance between the first focal point and any point on the first curved surface;

(ii) a first feedhorn disposed proximal to the first focal point; and

(iii) a second feedhorn disposed proximal to the second focal point;

(B) a second antenna unit, comprising;

(i) a second substantially rigid metallic body, the second body defining a third curved surface and a fourth curved surface, the third curved surface defining a third focal point, the fourth curved surface defining a fourth focal point, the third curved surface defining a third axis along which the third curved surface can transmit a second transmitted electromagnetic beam, the fourth curved surface defining a fourth axis along which the fourth curved surface can receive an electromagnetic beam, the third axis and the fourth axis being substantially parallel, the third focal point and the fourth focal point being separated by a second separation distance, the second separation distance being greater than a distance between the third focal point and any point on the third curved surface;

(ii) a third feedhorn disposed proximal to the third focal point; and

(iii) a fourth feedhorn disposed proximal to the fourth focal point;

the first and second antenna units being separated from one another and aligned such that the first and third axes are substantially parallel, such that the fourth curved surface can receive the first transmitted electromagnetic beam, and such that the second curved surface can receive the second transmitted electromagnetic beam.

17. An antenna unit, comprising:

a first set of wires defining a first dish shaped surface, the first dish shaped surface defining a first focal point and a first axis along which the first set of wires can transmit a first electromagnetic beam, the first electromagnetic beam being characterized by a first polarization;

a second set of wires defining a second dish shaped surface, the second dish shaped surface defining a second focal point and a second axis along which the second set of wires can transmit a second electromagnetic beam, the first axis and the second axis being substantially parallel, the second electromagnetic beam being characterized by a second polarization, the first polarization being substantially orthogonal to the second polarization, the first and second dish shaped surfaces being disposed such that the first focal point is outside of the second electromagnetic beam and such that the second focal point is outside of the first electromagnetic beam;

a first feedhorn disposed proximal to the first focal point; and

a second feedhorn disposed proximal to the second focal point.

18. An antenna unit, comprising:

a first set of wires defining a first dish shaped surface, the first dish shaped surface defining a first focal point and a first axis along which the first set of wires can receive a first electromagnetic beam, the first electromagnetic beam being characterized by a first polarization;

a second set of wires defining a second dish shaped surface, the second dish shaped surface defining a second focal point and a second axis along which the second set of wires can receive a second electromagnetic beam, the first axis and the second axis being substantially parallel, the second electromagnetic beam being characterized by a second polarization, the first polarization being substantially orthogonal to the second polarization, the first and second dish shaped surfaces being disposed such that the first focal point is outside of the second electromagnetic beam and such that the second focal point is outside of the first electromagnetic beam;

a first feedhorn disposed proximal to the first focal point; and

a second feedhorn disposed proximal to the second focal point.

19. An antenna unit, comprising:

a first set of wires defining a first dish shaped surface, the first dish shaped surface defining a first focal point and a first axis along which the first set of wires can transmit a first electromagnetic beam, the first electromagnetic beam being characterized by a first polarization;

a second set of wires defining a second dish shaped surface, the second dish shaped surface defining a second focal point and a second axis along which the second set of wires can receive a second electromagnetic beam, the first axis and the second axis being substantially parallel, the second electromagnetic beam being characterized by a second polarization, the first polarization being substantially orthogonal to the second polarization, the first and second dish shaped surfaces being disposed such that the first focal point is outside of the second electromagnetic beam and such that the second focal point is outside of the first electromagnetic beam;

a first feedhorn disposed proximal to the first focal point; and

a second feedhorn disposed proximal to the second focal point.

20. An antenna unit, comprising:

a first feedhorn;

a second feedhorn; and

a substantially rigid metallic body, the body defining a first curved surface and a second curved surface, the first curved surface defining a first focal point, the first focal point being located within the first feedhorn, the second curved surface defining a second focal point, the second focal point being located within the second feedhorn, the first curved surface defining a transmit axis, the second curved surface defining a receive axis, the transmit axis and the receive axis being substantially parallel, the first focal point and the second focal point being separated by a separation distance, the separation distance being greater than a distance between the first focal point and any point on the first curved surface, the first curved surface being configured to reflect a beam received from the first feedhorn and thereby generate a transmitted electromagnetic beam, the second curved surface being configured to reflect a received electromagnetic beam towards the second feedhorn.