Scalable Wireless Mesh Networks

• US 20070297371A1
• Filed: 05/01/2007
• Published: 12/27/2007
• Est. Priority Date: 05/01/2006
• Status: Active Grant

• Current Assignee: Hong Kong University of Science and Technology
• Original Assignee: Hong Kong University of Science and Technology
• Inventors: Lea, Chin Tau
• Granted Patent: US 8,761,125 B2
• Time in Patent Office: Days
• US Class Current: 370/334
• CPC Class Codes: H04L 45/20 Hop count for routing purposes, e.g. TTL
• CPC Class Codes: H04W 40/20 based on geographic position or location
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

Multi-hop architectures of a wireless mesh network (MWN) compatible with the existing WiFi devices and potentially offering a much larger total capacity than a single-hop WiFi cell. The proposed architectures are scalable and do not have the hidden-terminal and the exposed-terminal problems intrinsic in a multi-hop environment that limited the space reuse efficiency of a WMN. The various disclosed architectures also support a fast and efficient location tracking scheme and can overcome the low space reuse efficiency in many of the existing WMN architectures.

Claims

1. Wireless network, comprising:

a plurality of access points;

individual ones of said access points being configured to communicate

(a) with any compatible mobile station which may be in proximity thereto, and also

(b) with adjacent other ones of said access points,

using a common wireless channel allocation for both (a) and (b).

2. The network of claim 1, wherein said access points use directional antenna of 120 degree.

3. The network of claim 1, wherein said user client terminal is an IEEE 802.11 physical-layer compatible device.

4. The network of claim 1, wherein said wireless network is IEEE 802.11 (WI-FI) compatible.

5. The network of claim 1, wherein said network is an infrastructure-mode wireless mesh network.

6. The network of claim 1, wherein, at any time, said mobile station is associated with only one of said access points.

7. The network of claim 1, wherein the transmit range of said client terminal is set to no more than the distance between said access points.

8. The network of claim 1, wherein said client terminal and said access points deploy RTS/CTS scheme before communicating with each other.

9. A wireless network, comprising:

a plurality of assigned-channel zones, each formed by an access point with directional antenna located at a corner of said zone; and

at least one cell covered by multiple ones of said zones with access point corners of said zones spaced around the borders of said cell;

wherein all said multiple zones within a single cell use a common channel allocation;

and wherein all cells adjacent to said cell use a different channel allocation.

10. The network of claim 9, wherein said access points use directional antenna of approximately 120 degrees.

11. The network of claim 9, wherein said channel allocations are IEEE 802.11 (WI-FI) compatible.

12. The network of claim 9, wherein said cell includes exactly three said zones.

13. A wireless network, comprising:

at least two adjacent access points,

at least one client terminal, and

an additional access point, identified in dependent on the address information of said client terminal, which is designated as an anchor access point for said client terminal;

wherein said adjacent access points use a common channel for communicating with each other and with said client terminal;

wherein at least one said access point updates the current location information of said client to said anchor access point;

and wherein said anchor access point provides routing for data packets destined for said client terminal;

whereby the frequency plans deployed in the network generate no hidden terminal and exposed terminal problems.

14. The network of claim 13, wherein said access points use directional antennae.

15. The network of claim 13, wherein said client terminal is an IEEE 802.11 physical-layer compatible device.

16. The network of claim 13, wherein said access points are configures as an infrastructure-mode wireless mesh network.

17. The network of claim 13, wherein ones of said two access points are located at two non-adjacent corners of a cell of an approximate hexagon shape and, at any time, said client is associated with only one of said APs with an association process defined in IEEE 802.11

18. The network of claim 13, wherein said client terminal and said access points deploy RTS/CTS scheme before communicating with each other.

19. The network of claim 13, wherein said additional access point is normally not within direct radio communications range of said client.

20. The network of claim 13, wherein said additional access point deploys a hashing table to maintain location information.

21-43. -43. (canceled)