Adaptive rate and reach optimization for wireless access networks

• US 8,503,419 B2
• Filed: 10/11/2011
• Issued: 08/06/2013
• Est. Priority Date: 05/12/2006
• Status: Active Grant

• Current Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Original Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Inventors: Savoor, Raj, Ou, Canhui, Wang, Jin
• Primary Examiner(s): Kasraian, Allahyar
• Application Number:
  US13/270,542
• Publication Number:
  US 20120087268A1
• Time in Patent Office: 665 Days
• Field of Search: 370/338, 455450-454, 455/127.1, 455/127.2, 455/452.1
• US Class Current: 370/338
• CPC Class Codes: H04L 41/22 comprising specially adapted graphical user interfaces [GUI]
• CPC Class Codes: H04L 41/5019 Ensuring fulfilment of SLA
• CPC Class Codes: H04W 16/18 Network planning tools
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 28/04 Error control
• CPC Class Codes: H04W 28/22 Negotiating communication rate
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 52/24 using SIR [Signal to Interference Ratio] or other wireless path parameters
• CPC Class Codes: H04W 72/54 based on quality criteria
• CPC Class Codes: H04W 72/541 using the level of interference
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A method controls a wireless local area network, which includes a centralized performance management controller and a plurality of network elements. The method includes determining interference between each network element and every other network element of the plurality of network elements, and populating an interference matrix identifying the interference between each combination of two network elements of the plurality of network elements. The method also includes generating an adjacency matrix based on the interference matrix indicating each combination of the two network elements of the plurality of network elements that has an unacceptable level of interference. The method further includes improving overall performance of the wireless local area network by reducing the unacceptable levels of interference indicated by the adjacency matrix.

Claims

1. A method for controlling a wireless local area network, which includes a centralized performance management controller and a plurality of network elements, the method comprising:

determining interference between each network element and every other network element of the plurality of network elements;

populating an interference matrix identifying the interference between each combination of two network elements of the plurality of network elements;

generating an adjacency matrix based on the interference matrix indicating each combination of the two network elements of the plurality of network elements that has an unacceptable level of interference; and

improving overall performance of the wireless local area network by reducing the unacceptable levels of interference indicated by the adjacency matrix,

wherein the method is performed both repetitively at predetermined fixed intervals to account for interference changes in the wireless local area network and at predetermined events, including when a new network element is added to the wireless local area network, and

wherein the generating an adjacency matrix includes modeling the adjacency matrix as a graph by creating a vertex for each network element, coloring the graph such that no adjacent vertices have the same color, and pruning most recently added nodes from the graph in a sequential order starting at the newest added node when a predetermined number of colors are insufficient to color the graph.

2. The method according to claim 1,

wherein at least one of the plurality of network elements is a mobile device.

3. The method according to claim 1,

wherein the plurality of network elements include a plurality of access points and a plurality of clients, with each access point serving at least one client.

4. The method according to claim 3,

wherein reducing the unacceptable levels of interference is performed by changing channel frequency allocation and transmit power for at least one pair of access point and client.

5. The method according to claim 4,

wherein transmit power is increased for at least one pair of access point and client when the at least one pair of access point and client is of sufficient distance away from other access point and client pairs such that unacceptable interference is not determined.

6. The method according to claim 3,

wherein at least one of the plurality of access points and at least one client served by the at least one of the plurality of access points are mobile devices.

7. The method according to claim 1,

wherein the graph is colored such that no adjacent vertices have the same color, each color representing a communication channel.

8. The method according to claim 7,

wherein each color represents one communication channel of a predetermined number of available communication channels.

9. The method according to claim 8, further comprising:

pruning at least one edge of the graph of the adjacency matrix so that the graph does not exceed the predetermined number of available communication channels when at least one additional network element is added to the local area network.

10. The method according to claim 9,

wherein the pruning includes reducing power to at least one vertex.

11. The method according to claim 10,

wherein at least one newly added network element has power reduced by the pruning.

12. The method according to claim 1,

wherein performance data relating to overall performance includes signal attenuation between network elements.

13. The method according to claim 1,

wherein performance data relating to overall performance includes signal to noise ratios.

14. The method according to claim 1,

wherein the determining interference includes determining interference with sources outside of the wireless local area network.

15. The method according to claim 1,

wherein the interference is determined by a radio link measurement.

16. A non-transitory tangible computer-readable storage medium encoded with an executable computer program for controlling a wireless local area network, which includes a centralized performance management controller and a plurality of network elements, and that when executed by a processor, causes the processor to perform operations comprising:

determining interference between each network element and every other network element of the plurality of network elements;

populating an interference matrix identifying the interference between each combination of two network elements of the plurality of network elements;

generating an adjacency matrix based on the interference matrix indicating each combination of the two network elements of the plurality of network elements that has an unacceptable level of interference; and

improving overall performance of the wireless local area network by reducing the unacceptable levels of interference indicated by the adjacency matrix,

wherein the operations are performed both repetitively at predetermined fixed intervals to account for interference changes in the wireless local area network and at predetermined events, including when a new network element is added to the wireless local area network, and

wherein the generating an adjacency matrix includes modeling the adjacency matrix as a graph by creating a vertex for each network element, coloring the graph such that no adjacent vertices have the same color, and pruning most recently added nodes from the graph in a sequential order starting at the newest added node when a predetermined number of colors are insufficient to color the graph.

17. A centralized performance management server for controlling a wireless local area network, which includes a plurality of network elements, the server comprising:

a processor for determining interference between each network element and every other network element of the plurality of network elements,

wherein the processor populates an interference matrix identifying the interference between each combination of two network elements of the plurality of network elements, and

wherein the processor generates an adjacency matrix based on the interference matrix indicating each combination of the two network elements of the plurality of network elements that has an unacceptable level of interference;

a storage for storing the interference matrix and the adjacency matrix; and

a controller for reducing the unacceptable levels of interference indicated by the adjacency matrix, thereby improving overall performance of the wireless local area network,

wherein the determining interference, the populating an interference matrix, the generating an adjacency matrix, and the improving overall performance are performed both repetitively at predetermined fixed intervals to account for interference changes in the wireless local area network and at predetermined events, including when a new network element is added to the wireless local area network, and

wherein generating an adjacency matrix includes modeling the adjacency matrix as a graph by creating a vertex for each network element, coloring the graph such that no adjacent vertices have the same color, and pruning most recently added nodes from the graph in a sequential order starting at the newest added node when a predetermined number of colors are insufficient to color the graph.