MIMO antenna system

• US 8,482,478 B2
• Filed: 11/12/2008
• Issued: 07/09/2013
• Est. Priority Date: 11/12/2008
• Status: Active Grant

• Current Assignee: Cambium Networks Limited (Cambium Networks Corporation)
• Original Assignee: Xirrus Incorporated
• Inventors: Hartenstein, Abraham
• Primary Examiner(s): LE, HOANGANH T
• Application Number:
  US12/269,567
• Publication Number:
  US 20100119002A1
• Time in Patent Office: 1,700 Days
• Field of Search: 343/893, 343/702, 375/267, 375/299
• US Class Current: 343/893
• CPC Class Codes: H01Q 21/205 providing an omnidirectional coverage turnstile aerials H01Q21/26
• CPC Class Codes: H01Q 21/24 Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001

Abstract

A wireless local area network (“WLAN”) antenna array (“WLANAA”) includes a circular housing having a plurality of radial sectors and a plurality of primary antenna elements configured as Multiple-Input, Multiple-Output (MIMO) antennas. Each primary antenna element, which includes multiple antennas connected to a single radio, being positioned within a radial sector of the plurality of radial sectors.

Claims

1. A wireless local area network (“

WLAN”

) antenna array (“

WLANAA”

) comprising;

a circular housing having a plurality of radial sectors; and

at least one radio in each radial sector, each of the at least one radio having;

a plurality of transceivers configured to send and receive wireless communications via a plurality of antenna elements configured as Mulitple-Input, Multiple-Output (“

MIMO”

) antennas wherein each of the plurality of antenna elements are positioned within an individual radial sector of the plurality of radial sectors; and

a baseband processor configured to process baseband signals to be sent or received by the plurality of transceivers.

2. The WLANAA of claim 1 further including at least one absorber element between each radial sector.

3. The WLANAA of claim 2 further including a plurality of absorber elements where each absorber element of the plurality of the absorber elements is located between an adjacent pair of primary antenna elements.

4. The WLANN of claim 1 where the plurality of radios are coupled to MIMO antennas that are of:

a first type of MIMO antennas for communicating signals that conform to the IEEE 802.11bg standard;

or

a second type of MIMO antennas for communicating signals that conform to the IEEE 802.11a standard.

5. The WLANAA of claim 4 where the first type of MIMO antennas include three dual-monopole antennas substantially evenly spaced along a perimeter of the radial sector of the radio connected to the first type of MIMO antennas.

6. The WLANAA of claim 4 where the second type of MIMO antennas include two dual-polarized antennas configured at the +45°

and −

45°

polarizations and one two-element dipole antenna orthogonal to the dual-polarized antennas.

7. The WLANAA of claim 6 where the two-element dipole antenna is embedded on a main RF printed circuit board (“

PCB”

) and the two dual-polarized antennas are printed on an antenna printed circuit board (“

antenna PCB”

) mounted substantially vertical relative to the main RF PCB.

8. The WLANAA of claim 7 where the two dual-polarized antennas are two element patch antenna sub-arrays configured at the +45°

and −

45°

polarizations.

9. The WLANAA of claim 4 where the second type of MIMO antennas include two linearly polarized antennas and one two-element dipole antenna orthogonal to the two linearly polarized antennas.

10. The WLANAA of claim 9 where the two-element dipole antenna is embedded on a main RF printed circuit board (“

PCB”

) and the two dual-polarized antennas are printed on an antenna printed circuit board (“

antenna PCB”

) mounted substantially vertical relative to the main RF PCB.

11. The WLANAA of claim 9 where the two linearly polarized antennas are two 1×

2 dipole element sub-arrays.

12. The WLANAA of claim 9 further comprising a reflector between the two 1×

2 dipole element sub-arrays.

13. The WLANAA of claim 1 where the at least one radio in each radial sector communicates over a first type of MIMO antennas for communicating signals that conform to the IEEE 802.11bg standard, the WLANAA further including:

a second plurality of radial sectors within the same circular housing, each of the second plurality of radial sectors including a second type of radio for communicating via a second plurality of antenna elements configured as second-type MIMO antennas for communicating signals that conform to the IEEE 802.11a standard.