Planar antenna for a wireless mesh network

• US 20040263390A1
• Filed: 06/26/2003
• Published: 12/30/2004
• Est. Priority Date: 06/26/2003
• Status: Active Grant

• Current Assignee: Trilliant Networks Incorporated
• Original Assignee: SkyPilot Networks Incorporated (Trilliant Networks Incorporated)
• Inventors: Rich, Mark J., Merenda, Joseph
• Granted Patent: US 7,053,853 B2
• Time in Patent Office: Days
• US Class Current: 343/700.0MS
• CPC Class Codes: H01Q 1/241 used in mobile communications, e.g. GSM H01Q1/247, H01Q1/248 take precedence
• CPC Class Codes: H01Q 21/065 Patch antenna array

Abstract

A planar antenna that facilitates directional communication to a mesh network. The antenna is housed in a relatively small, planar package that can easily be attached to a window pane to enable the antenna to communicate with a neighboring rooftop mounted node of the mesh network. The package contains an M by N element phased array, where M and N are integers greater than one. The array is driven by microwave signals supplied from a P-angle phase shifting circuit, where P is an integer greater than one. Thus, the antenna synthesizes a single main beam and the antenna'"'"'s main beam can be electrically “pointed” in one of P directions. In one embodiment of the invention, the array comprises 40 physical elements (8×5 elements) and has three selectable directions (i.e., the phase shifters provide +90, 0 and −90 degree shifts that move the beam left 45 degrees, center and right 45 degrees).

Claims

1. An antenna for communicating with a mesh network comprising:

a plurality of phased array elements configured in an M×

N array, where M and N are integers greater than 1, said plurality of phased array elements adapted to selectively synthesize one or more radiation patterns for communicating with neighboring nodes of a mesh network; and

a drive circuit for supplying microwave power to the plurality of phased array elements and for controlling a directionality of the radiation pattern.

2. The antenna of claim 1 further comprising:

an enclosure for housing the plurality of phased array elements and the drive circuit, where said enclosure is approximately 3 cm thick.

3. The antenna of claim 1 wherein the plurality of phased array elements are positioned upon a substrate having dimensions of about 25 cm by about 20 cm.

4. The antenna of claim 1 wherein the directionality is switched in P discrete directions, where P is an integer greater than 1.

5. The antenna of claim 4 wherein P is three corresponding to +45 degrees, center, and −

45 degrees.

6. The antenna of claim 1 wherein the elevation of the radiation pattern is fixed.

7. The antenna of claim 1 wherein the elevation of the radiation pattern is fixed at an incline from horizontal.

8. The antenna of claim 1 wherein the drive circuit is coupled to a transceiver and modem circuit.

9. The antenna of claim 1 further comprising an enclosure for the drive circuit and plurality of phased array elements, where the enclosure comprises an adhesive element.

10. The antenna of claim 9 wherein the adhesive element is adapted for attaching the enclosure to a flat surface.

11. The antenna of claim 1 further comprising a multi-layer circuit board that support the plurality of antenna elements, a ground plane, and the driver circuit.

12. The antenna of claim 1 further comprising a foam core substrate for supporting the plurality of phased array elements.

15. The antenna of claim 12 wherein the power divider comprises attenuation in each of the M signal paths.

13. An antenna for communicating with a mesh network comprising:

a multi-layer circuit board having a first side and a second side, with a ground plane formed within the multi-layer circuit board;

an antenna array, affixed to the first side of the multi-layer circuit board, having M×

N array of antenna elements, where M and N are integers greater than 1, said antenna array adapted to selectively synthesize one or more radiation patterns for communicating with neighboring nodes of said mesh network;

a driver circuit, affixed to the second side of the multi-layer circuit board, having a power divider that divides an input microwave signal into M signal paths, a plurality of phase shift circuits are coupled to M−

1 paths and the output of each phase shift circuit is coupled to an antenna element, one of the M signal paths is coupled directly to an antenna element.

14. The antenna of claim 13 wherein M is 5 and N is 8.

16. The antenna of claim 13 wherein the phase sift circuits comprise switched hybrid couplers that, in response to a control signal, phase shift the signals on the M−

1 paths by a discrete phase amount.

17. The antenna of claim 16 wherein the discrete phase shift is at least one of −

90 degrees, 0 degrees and +90 degrees.

18. The antenna of claim 17 wherein the discrete phase shifts cause a main beam of a radiation pattern formed by the array to be directed 0 degrees, +45 degrees and −

45 degrees.

19. The antenna of claim 13 further comprising a modem circuit and a transceiver circuit.