Adaptive rate and reach optimization for wireless access networks

• US 8,064,413 B2
• Filed: 05/12/2006
• Issued: 11/22/2011
• Est. Priority Date: 05/12/2006
• Status: Expired due to Fees

• Current Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Original Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Inventors: Wang, Jin, Savoor, Raj, Ou, Canhui
• Primary Examiner(s): Pérez-Gutiérrez; Rafael
• Assistant Examiner(s): Kasraian; Allahyar
• Application Number:
  US11/432,490
• Publication Number:
  US 20070263587A1
• Time in Patent Office: 2,020 Days
• Field of Search: 455450-454, 455/127.1, 455/127.2, 370/338
• 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 wireless local area network (WLAN) control system includes network elements (such as access points and clients) and a centralized dynamic performance management system. The network elements measure signal attenuation in communications with other WLAN network elements. The dynamic performance management system receives signal attenuation data from the network elements, and determines a frequency and/or transmission power level for each of the network elements to reduce interference with the other WLAN network elements. The dynamic performance management system also transmits instructions to each network element to control the frequency and/or transmission power level of the network elements.

Claims

1. A tangible computer readable medium storing a program for controlling a plurality of wireless local area network elements of a plurality of wireless local area networks, comprising:

a defining segment that defines the plurality of wireless local area network elements and the plurality of wireless local area networks;

a network initiation segment that instructs each wireless local network element to attempt to communicate with each other wireless local network element in each of the plurality of wireless local area networks to generate interference data;

a wireless local area network element polling code segment that receives the interference data from the plurality of wireless local area network elements, the interference data indicating network elements that interfere with the other wireless local area network elements;

an interference matrix segment that, based upon the interference data, generates an interference matrix that corresponds to a representation of network interference, and includes determined interference data for each set of wireless local area networks;

a frequency/power determination code segment that determines a frequency and/or transmission power level for each wireless local area network element to reduce interference with the interfering network elements, the frequency/power determination code segment determining the power level to be an increased power level when a signal attenuation value between an access point and a client is above a threshold value; and

a transmitting code segment that transmits instructions to each wireless local area network element to control the frequency and/or transmission power level of the wireless local area network elements,

wherein the frequency/power determination code segment determines the frequency and/or the transmission power level by generating an adjacency matrix, showing the acceptable and unacceptable levels of interference between each set of two wireless local network elements, based upon the interference matrix, and by coloring a graph, using a predetermined maximum number of colors, based upon the generated adjacency matrix,

wherein the frequency/power determination code segment prunes most recently added nodes from the graph in a sequential order starting with a newest added node, when the predetermined maximum number of colors are insufficient to color the graph, and continues pruning until the predetermined maximum number of colors are sufficient to color the graph, and

wherein the interference data includes determined interference data between every possible combination of two wireless local area network elements that are included in the plurality of wireless local area networks, and wherein each combination of two wireless local area network elements is designated as a set of wireless local area networks.

2. The medium of claim 1, in which each of the wireless local area networks comprises an 802.11 network.

3. The medium of claim 2, in which the instructions comprise a dynamic frequency selection instruction.

4. The medium of claim 2, in which the instructions comprise a transmit power control instruction.

5. The medium of claim 1, in which each of the wireless local area networks comprises an 802.16 network.

6. The medium of claim 1, in which the predetermined maximum number of colors is 14, which is equal to a number of channels available in the wireless local area networks.

7. The medium of claim 1, in which the transmission power level is a reduced power level for at least one of the plurality of wireless local area network elements when the graph coloring requires more than the predetermined maximum number of colors, which is equal to the number of channels available in the wireless local area networks, in order to reduce interference.

8. A dynamic performance management system for controlling wireless networks, comprising:

a plurality of defined wireless local area network elements that attempt to communicate with each other wireless local area network elements during an initiation phase to generate interference data, wherein each wireless local area network element is included in at least one of a plurality of wireless local area networks;

a receiver that receives the interference data from the plurality of wireless local area network elements, the interference data indicating network elements that interfere with the other wireless local area network elements;

an interference matrix system that generates an interference matrix based upon the interference data that corresponds to a representation of network interference, and includes determined interference data for each set of wireless local area networks;

a frequency/power determination system that determines a frequency and/or transmission power level for each wireless local area network element to reduce interference with the interfering network elements, the frequency/power determination system determining the power level to be an increased power level when a signal attenuation value between an access point and a client is above a threshold value; and

a transmitter that transmits instructions to each wireless local area network element to control the frequency and/or transmission power level of the wireless local area network elements,

wherein the frequency/power determination system determines the frequency and/or the transmission power level by generating an adjacency matrix, showing the acceptable and unacceptable levels of interference between each set of two wireless local network elements, based upon the interference matrix, and by coloring a graph, using a predetermined maximum number of colors, based upon the generated adjacency matrix,

wherein the frequency/power determination system prunes most recently added nodes from the graph in a sequential order starting with a newest added node, when the predetermined maximum number of colors are insufficient to color the graph, and continues pruning until the predetermined maximum number of colors are sufficient to color the graph, and

wherein the interference data includes determined interference data between every possible combination of two wireless local area network elements that are included in the plurality of wireless local area networks, and wherein each combination of two wireless local area network elements is designated as a set of wireless local area networks.

9. The system of claim 8, in which at least one of the wireless local area network elements comprises an access point.

10. The system of claim 9, in which each of the wireless local area networks comprises an 802.11 network.

11. The system of claim 10, in which the instructions comprise a dynamic frequency selection instruction.

12. The system of claim 10, in which the instructions comprise a transmit power control instruction.

13. The system of claim 9, in which each of the wireless local area networks comprises an 802.16 network.

14. A wireless local area network control system comprising:

a plurality of defined access points that measure signal attenuation in communications with a plurality of defined other wireless local area network elements, wherein the plurality of access points and the plurality of other wireless local area network elements attempt to communicate with each other to generate signal attenuation data, wherein the signal attenuation data includes determined interference data between every possible combination of two access points, two wireless local area network elements, and one access point and one wireless local area network element, and wherein each combination is designated as an attenuation data set;

a dynamic performance management system that receives the signal attenuation data from the plurality of access points, generates an interference matrix based upon the signal attenuation data that corresponds to a representation of network interference and that includes information representing each attenuation data set, determines a frequency and/or transmission power level for each of the plurality of access points to reduce interference with the other wireless local area network elements, and transmits instructions to each access point to control the frequency and/or transmission power level of the access points,

wherein the dynamic performance management system determines the power level to be an increased power level when a signal attenuation value between an access point and a client is above a threshold value,

wherein the dynamic performance management system determines the frequency and/or the transmission power level by generating an adjacency matrix, showing the acceptable and unacceptable levels of interference between each set of two wireless local network elements, based upon the interference matrix, and by coloring a graph, using a predetermined maximum number of colors, based upon the generated adjacency matrix, and

wherein the dynamic performance management system prunes most recently added nodes from the graph in a sequential order starting with a newest added node, when the predetermined maximum number of colors are insufficient to color the graph, and continues pruning until the predetermined maximum number of colors are sufficient to color the graph.

15. A method for controlling a plurality of wireless local area network elements of a plurality of wireless local area networks, comprising:

defining the plurality of wireless local area network elements and the plurality wireless local area networks;

generating interference data through an initiation phase that instructs each wireless local network element in each of the plurality of wireless local area networks to attempt to communicate with each other wireless local network element to generate interference data, wherein each combination of two wireless local area network elements is designated as a set of wireless local area networks;

receiving the interference data from the plurality of wireless local area network elements, the interference data indicating network elements that interfere with the other wireless local area network elements;

generating an interference matrix based upon the interference data that corresponds to a representation of network interference, and includes determined interference data for each set of wireless local area networks;

determining a frequency and/or transmission power level for each wireless local area network element to reduce interference with the interfering network elements, including determining the power level to be an increased power level when a signal attenuation value between an access point and a client is above a threshold value, in which determining the frequency and/or transmission power level is by generating an adjacency matrix based upon the interference matrix, wherein the adjacency matrix shows the acceptable and unacceptable levels of interference between each set of two wireless local network elements; and

transmitting instructions to each wireless local area network element to control the frequency and/or transmission power level of the wireless local area network elements,

wherein determining the frequency and/or the transmission power level includes generating an adjacency matrix, showing the acceptable and unacceptable levels of interference between each set of two wireless local network elements, based upon the interference matrix, and by coloring a graph, using a predetermined maximum number of colors, based upon the generated adjacency matrix,

wherein determining the frequency and/or the transmission power level includes pruning most recently added nodes from the graph in a sequential order starting with a newest added node, when the predetermined maximum number of colors are insufficient to color the graph, and continues pruning until the predetermined maximum number of colors are sufficient to color the graph, and

wherein the interference data includes determined interference data between every possible combination of two wireless local area network elements that are included in the plurality of wireless local area networks.