Method of coordinating fault detection responses by access nodes of a network

• US 9,204,315 B2
• Filed: 06/20/2011
• Issued: 12/01/2015
• Est. Priority Date: 06/20/2011
• Status: Active Grant

• Current Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Original Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Inventors: Sridhar, Kamakshi
• Primary Examiner(s): Sam, Phirin
• Application Number:
  US13/163,814
• Publication Number:
  US 20120320766A1
• Time in Patent Office: 1,625 Days
• US Class Current: 1/1
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 52/0206 in access points, e.g. base stations access point devices per se H04W88/08
• CPC Class Codes: H04W 72/52 based on load
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

The present invention provides a method of coordinating access nodes when a sleeping cell is detected. The method may include modifying a coverage area of an access node to compensate for lost coverage in a sleeping cell detected by the access node. The access node implements resource allocation algorithms and a cell identification algorithm. The method may also include instructing the resource allocation algorithms and/or the cell identification algorithm to perform a predetermined action concurrently with the modification.

Claims

1. A method, comprising:

detecting a sleeping cell at an access node;

modifying at least one coverage area of the access node to compensate for lost coverage in the sleeping cell, wherein the access node implements resource allocation algorithms; and

instructing the resource allocation algorithms to perform one of a plurality of predetermined actions concurrently with said modification depending on whether at least one quality of experience (QoE) is being met for at least one user.

2. The method of claim 1, wherein modifying said at least one coverage area comprises changing at least one tilt of at least one antenna used by the access node.

3. The method of claim 1, further comprising initiating a physical cell identifier algorithm to allocate collision-free and confusion-free physical cell identifiers to the access node and one or more neighboring access nodes.

4. The method of claim 1, comprising measuring the at least one QoE for the at least one user being served by the access node concurrently with modifying said at least one coverage area.

5. The method of claim 4, wherein measuring said at least one QoE comprises measuring at least one of an uplink bit rate, a downlink bit rate, an estimated air interface delay, or a packet loss rate for said at least one user.

6. The method of claim 1, wherein the access node concurrently modifies said at least one coverage area and instructs the resource allocation algorithms to perform the one of the plurality of predetermined actions substantially continuously until a convergence criterion is satisfied.

7. The method of claim 1, comprising:

determining that the sleeping cell has awakened;

modifying said at least one coverage area of the access node to account for resumed coverage in the previously sleeping cell; and

instructing the resource allocation algorithms to perform another one of the plurality of predetermined actions concurrently with said modification.

8. The method of claim 7, wherein the access node concurrently modifies said at least one coverage area and instructs the resource allocation algorithms to perform the another one of the plurality of predetermined actions substantially continuously until a convergence criterion is satisfied.

9. The method of claim 1, further comprising instructing a load-balancing algorithm to load balance traffic away from the access node in response to said modification, wherein instructing the load-balancing algorithm to load balance traffic away from the access node comprises determining whether to perform load balancing on at least one user based on the at least one QoE for said at least one user and at least one likelihood that a target QoE for said at least one user will be met after load-balancing.

10. A method, comprising:

modifying at least one coverage area of an access node to compensate for lost coverage in a sleeping cell detected by the access node, wherein the access node implements resource allocation algorithms and a cell identification algorithm; and

instructing at least one of the resource allocation algorithms or the cell identification algorithm to perform a predetermined action concurrently with said modification, wherein instructing said at least one of the resource allocation algorithms to perform the predetermined action comprises instructing a call admission control algorithms to admit new guaranteed bit rate users when [said] at least one QoE is being met for said at least one user and instructing the call admission control algorithm to deny new guaranteed bit rate users when said at least one QoE is not being met for said at least one user.

11. The method of claim 10, wherein instructing the call admission control algorithms to admit or deny new guaranteed bit rate users comprises reconfiguring the call admission control algorithm using a first set of admission thresholds when said at least one QoE is being met for said at least one user and a second set of admission thresholds when said at least one QoE is not being met for said at least one user.

12. A method, comprising:

detecting a sleeping cell at an access node, wherein the access node implements a load-balancing algorithm;

modifying at least one coverage area of the access node to compensate for lost coverage in the sleeping cell; and

instructing the load-balancing algorithm to load balance traffic away from the access node concurrently with said modification, wherein instructing the load-balancing algorithm to load balance traffic away from the access node comprises determining whether to perform load balancing on at least one user based on at least one measured quality of experience (QoE) for said at least one user and at least one likelihood that a target QoE for said at least one user will be met after load-balancing.

13. The method of claim 12, wherein determining whether to perform load balancing on said at least one user comprises load-balancing more traffic when a degradation in said at least one measured QoE is relatively large and load-balancing less traffic when the degradation is relatively small.

14. The method of claim 12, wherein detecting the sleeping cell comprises detecting a sleeping cell condition on at least one carrier or radio access technology supported by the sleeping cell.

15. The method of claim 14, wherein instructing the load-balancing algorithm to load balance traffic away from the access node comprises instructing the load-balancing algorithm to load balance traffic away from said at least one carrier or radio access technology that is experiencing the sleeping cell condition.

16. A method, comprising:

detecting a sleeping cell at an access node, wherein the access node implements a cell identification algorithm;

modifying at least one coverage area of the access node to compensate for lost coverage in the sleeping cell; and

executing the cell identification algorithm in response to said modification.

17. The method of claim 16, wherein modifying said at least one coverage area comprises changing at least one tilt of at least one antenna used by the access node.

18. The method of claim 16, wherein executing the cell identification algorithm comprises executing the cell identification algorithm at the access node concurrently with executing cell identification algorithms at one or more neighboring access nodes to allocate collision-free and confusion-free cell identifiers to the access node and the one or more neighboring access node.

19. The method of claim 16, further comprising instructing at least one resource allocation algorithm to perform one of a plurality of predetermined actions concurrently with said modification depending on whether at least one quality of experience (QoE) is being met for at least one user.

20. The method of claim 19, further comprising instructing a load-balancing algorithm to load balance traffic away from the access node concurrently with said modification, wherein instructing the load-balancing algorithm to load balance traffic away from the access node comprises determining whether to perform load balancing on at least one user based on the at least one QoE for said at least one user and at least one likelihood that a target QoE for said at least one user will be met after load-balancing.

21. An access node, comprising:

a computer system configured to detect a sleeping cell and modify at least one coverage area of the access node to compensate for lost coverage in the sleeping cell, wherein the computer system implements a resource allocation algorithm, and wherein the resource allocation algorithm performs one of a plurality of predetermined actions concurrently with the modification depending on whether at least one quality of experience (QoE) is being met for at least one user.

22. The access node of claim 21, further comprising:

at least one antenna, wherein the computer system is configured to change at least one tilt of the at least one antenna to modify the at least one coverage area of the access node.

23. The access node of claim 21, wherein the computer system implements a physical cell identifier algorithm to allocate collision-free and confusion-free physical cell identifiers to the access node and one or more neighboring access nodes in response to modifying the at least one coverage area of the access node.

24. The access node of claim 21, wherein the computer system implements a call admission control algorithm to admit new guaranteed bit rate users when the at least one QoE is being met for the at least one user and deny new guaranteed bit rate users when the at least one QoE is not being met for the at least one user.

25. The access node of claim 24, wherein the computer system is configured to reconfigure the call admission control algorithm using a first set of admission thresholds when the at least one QoE is being met for the at least one user and a second set of admission thresholds when the at least one QoE is not being met for the at least one user.

26. The access node of claim 21, wherein the computer system is configured to determine that the sleeping cell has awakened, modify the at least one coverage area of the access node to account for resumed coverage in the previously sleeping cell, and instruct the resource allocation algorithm to perform another one of the plurality of predetermined actions concurrently with the modification performed in response to the sleeping cell awakening.

27. The access node of claim 21, wherein the computer system implements a load-balancing algorithm to load balance traffic away from the access node in response to the modification, and wherein the computer system is configured to instruct the load-balancing algorithm to determine whether to perform load balancing on at least one user based on the at least one QoE for the at least one user and at least one likelihood that a target QoE for the at least one user will be met after load-balancing.

28. An access node, comprising:

a computer system that implements a cell identification algorithm, wherein the computer system is configured to detect a sleeping cell, modify at least one coverage area of the access node to compensate for lost coverage in the sleeping cell, and execute the cell identification algorithm in response to the modification.

29. The access node of claim 28, further comprising:

at least one antenna, and wherein the computer system is configured to change at least one tilt of at least one antenna used by the access node.

30. An access node, comprising:

a computer system that implements a load-balancing algorithm, wherein the computer system is configured to detect a sleeping cell, modify at least one coverage area of the access node to compensate for lost coverage in the sleeping cell, and instruct the load-balancing algorithm to load balance traffic away from the access node concurrently with the modification, wherein instructing the load-balancing algorithm to load balance traffic away from the access node comprises determining whether to perform load balancing on at least one user based on at least one measured quality of experience (QoE) for the at least one user and at least one likelihood that a target QoE for the at least one user will be met after load-balancing.