System and method for faulty mobile unit isolation

• US 5,812,636 A
• Filed: 09/06/1996
• Issued: 09/22/1998
• Est. Priority Date: 09/06/1996
• Status: Expired due to Term

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Northern Telecom Limited (Nortel Networks Corporation)
• Inventors: Tseng, Stone, Basu, Kalyan
• Primary Examiner(s): LOOMIS, PAUL A
• Application Number:
  US08/711,633
• Time in Patent Office: 746 Days
• Field of Search: 379/2, 379/10, 379/15, 379/22, 379/24, 379/26, 379/27, 379/29, 379/30, 379/32, 379/34, 379/113, 379/133, 379/134, 455/423, 455/424, 455/425, 455/67.1, 455/67.3, 455/226.1, 455/226.2, 455/226.3, 370/242, 370/250, 370/251, 375/224, 375/227
• US Class Current: 455/423
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements

Abstract

A wireless network, having a plurality of mobile units operating in a cell of the wireless network, isolates a faulty mobile unit that jams the control channel thereby preventing communication by the other mobile units in the cell. A system and method for isolating the faulty mobile unit monitors the cell traffic pattern among the mobile units in the cell to detect an abnormality, determines whether the abnormality is due to the faulty mobile unit or a problem with the wireless network, and if the abnormality is due to the faulty mobile unit, communicates with the mobile units operating within the cell to isolate the faulty mobile unit.

Claims

1. A method for isolating a faulty mobile unit from a plurality of mobile units operating in a cell of a wireless network, comprising the steps of:

monitoring traffic among the mobile units in the cell to detect an abnormality in a cell traffic pattern;

determining whether the abnormality is due to the faulty mobile unit; and

communicating with the plurality of mobile units in the cell, if the abnormality is due to the faulty mobile unit, to isolate the faulty mobile unit.

2. The method of claim 1, wherein the determining step includes the step of

determining the presence of a control channel signal detection failure when the cell traffic pattern exhibits an abnormality.

3. The method of claim 2, wherein the determining step further includes the step of

checking signal reception on the control channel for an abnormal condition when a control channel signal detection failure is present.

4. The method of claim 3, wherein the determining step further includes the step of

performing closed-loop control channel diagnostics analysis to determine a source of the control channel signal detection failure and the cell traffic pattern abnormality when the control channel signal reception indicates an abnormal condition.

5. The method of claim 4, wherein the communicating step includes the step of

requesting registration from the mobile units in the cell when the closed-loop control channel diagnostics analysis indicates that the faulty mobile unit is the source of the control channel signal detection failure and the abnormality in the cell traffic pattern.

6. The method of claim 5, wherein the communicating step further includes the steps of

generating a list of potentially faulty mobile units from mobile units responding to the registration request;

and

isolating the faulty mobile unit from the list of potentially faulty mobile units.

7. The method of claim 6, wherein the list generating step includes the step of

querying respective home location registers of the mobile units on the list of potentially faulty mobile units.

8. The method of claim 7, wherein the isolating step includes the step of

examining contents of the home location registers queried.

9. The method of claim 5, wherein the requesting step includes the step of

requesting registration only from mobile units in the cell that meet predetermined criteria.

10. The method of claim 1, wherein the communicating step includes the step of

requesting registration from the mobile units in the cell when the abnormality in the cell traffic pattern is due to the faulty mobile unit.

11. The method of claim 10, wherein the communicating step further includes the steps of

generating a list of potentially faulty mobile units from mobile units responding to the registration request;

and

isolating the faulty mobile unit from the list of potentially faulty mobile units.

12. The method of claim 11, wherein the list generating step includes the step of

querying respective home location registers of the mobile units on the list of potentially faulty mobile units.

13. The method of claim 12, wherein the isolating step includes the step of

examining contents of the home location registers queried.

14. The method of claim 10, wherein the requesting step includes the step of

requesting registration only from mobile units in the cell that meet predetermined criteria.

15. The method of claim 1, further including the step of

recommending actions to be taken to compensate for the faulty mobile unit.

16. A method for isolating a faulty mobile unit from a plurality of mobile units operating in a cell of a wireless network, comprising the steps of:

monitoring traffic among the mobile units in the cell;

determining the presence of a control channel signal detection failure when the monitored traffic pattern exhibits a decrease in cell traffic that exceeds predetermined criteria;

checking signal reception on the control channel for an abnormal condition when a control channel signal detection failure is present;

performing closed-loop control channel diagnostics analysis to determine a source of the cell traffic pattern decrease when the control channel signal reception indicates an abnormal condition; and

communicating with the plurality of mobile units in the cell, if the cell traffic pattern decrease is due to the faulty mobile unit, to isolate the faulty mobile unit.

17. The method of claim 16, wherein the communicating step includes the step of

requesting registration from the mobile units in the cell when the decrease in the cell traffic pattern is due to the faulty mobile unit.

18. The method of claim 17, wherein the communicating step further includes the steps of

generating a list of potentially faulty mobile units from mobile units responding to the registration request;

and

isolating the faulty mobile unit from the list of potentially faulty mobile units.

19. The method of claim 18, wherein the list generating step includes the step of

querying respective home location registers of the mobile units on the list of potentially faulty mobile units.

20. The method of claim 19, wherein the isolating step includes the step of

examining contents of the home location registers queried.

21. The method of claim 17, wherein the requesting step includes the step of

requesting registration only from mobile units in the cell that meet predetermined criteria.

22. The method of claim 16, further including the step of

recommending actions to be taken to compensate for the faulty mobile unit.

23. A method for isolating a faulty mobile unit from a plurality of mobile units operating in a cell of a wireless network, comprising the steps of:

monitoring traffic among the mobile units in the cell to detect an abnormality in a cell traffic pattern;

determining whether the abnormality is due to the faulty mobile unit;

requesting registration from the mobile units in the cell if the abnormality is due to the faulty mobile unit;

generating a list of potentially faulty mobile units from mobile units responding to the registration request; and

isolating the faulty mobile unit from the list of potentially faulty mobile units.

24. A system for isolating a faulty mobile unit of a plurality of mobile units operating in a cell of a wireless network, comprising:

means for monitoring traffic among the mobile units in the cell to detect an abnormality in a cell traffic pattern;

means for determining whether the abnormality is due to the faulty mobile unit; and

means for communicating with the plurality of mobile units in the cell, if the abnormality is due to the faulty mobile unit, to isolate the faulty mobile unit.

25. The system of claim 24, wherein the determining means includes

means for determining the presence of a control channel signal detection failure when the cell traffic pattern exhibits an abnormality.

26. The system of claim 25, wherein the determining means further includes

means for checking signal reception on the control channel for an abnormal condition when a control channel signal detection failure is present.

27. The system of claim 26, wherein the determining means further includes

means for performing closed-loop control channel diagnostics analysis to determine a source of the control channel signal detection failure and the cell traffic pattern abnormality when the control channel signal reception indicates an abnormal condition.

28. The system of claim 27, wherein the communicating means includes

means for requesting registration from the mobile units in the cell when the closed-loop control channel diagnostics analysis indicates that the faulty mobile unit is the source of the control channel signal detection failure and the abnormality in the cell traffic pattern.

29. The system of claim 28, wherein the communicating means further includes

means for generating a list of potentially faulty mobile units from mobile units responding to the registration request;

and

means for isolating the faulty mobile unit from the list of potentially faulty mobile units.

30. The system of claim 29, wherein the list generating means includes

means for querying respective home location registers of the mobile units on the list of potentially faulty mobile units.

31. The system of claim 30, wherein the isolating means includes

means for examining contents of the home location registers queried.

32. The system of claim 28, wherein the requesting means includes

means for requesting registration only from mobile units in the cell that meet predetermined criteria.

33. The system of claim 24, wherein the communicating means includes

means for requesting registration from the mobile units in the cell when the abnormality in the cell traffic pattern is due to the faulty mobile unit.

34. The system of claim 33, wherein the communicating means further includes

means for generating a list of potentially faulty mobile units from mobile units responding to the registration request;

and

means for isolating the faulty mobile unit from the list of potentially faulty mobile units.

35. The system of claim 34, wherein the list generating means includes

means for querying respective home location registers of the mobile units on the list of potentially faulty mobile units.

36. The system of claim 35, wherein the isolating means includes

means for examining contents of the home location registers queried.

37. The system of claim 33, wherein the requesting means includes

means for requesting registration only from mobile units in the cell that meet predetermined criteria.

38. The system of claim 24, further including

means for recommending actions to be taken to compensate for the faulty mobile unit.

39. The system of claim 24, wherein the wireless network further includes

a mobile switching center providing communication among the plurality of cells.

40. The system of claim 39, wherein the system is located within the mobile switching center.

41. A system for isolating a faulty mobile unit of a plurality of mobile units operating in a cell of a wireless network, the plurality of mobile units communicating with the cell over a control channel, the system comprising:

means for monitoring traffic among the mobile units in the cell;

means for determining the presence of a control channel signal detection failure when the monitored traffic pattern exhibits a decrease in cell traffic that exceeds predetermined criteria;

means for checking signal reception on the control channel for an abnormal condition when a control channel signal detection failure is present;

means for performing closed-loop control channel diagnostics analysis to determine a source of the cell traffic pattern decrease when the control channel signal reception indicates an abnormal condition; and

means for communicating with the plurality of mobile units in the cell, if the cell traffic pattern decrease is due to the faulty mobile unit, to isolate the faulty mobile unit.

42. The system of claim 41, wherein the communicating means includes

means for requesting registration from the mobile units in the cell when the decrease in the cell traffic pattern is due to the faulty mobile unit.

43. The system of claim 42, wherein the communicating means further includes

means for generating a list of potentially faulty mobile units from mobile units responding to the registration request;

and

means for isolating the faulty mobile unit from the list of potentially faulty mobile units.

44. The system of claim 43, wherein the list generating means includes

means for querying respective home location registers of the mobile units on the list of potentially faulty mobile units.

45. The system of claim 44, wherein the isolating means includes

means for examining contents of the home location registers queried.

46. The system of claim 42, wherein the requesting means includes

means for requesting registration only from mobile units in the cell that meet predetermined criteria.

47. The system of claim 41, further including

means for recommending actions to be taken to compensate for the faulty mobile unit.

48. A system for isolating a faulty mobile unit of a plurality of mobile units operating in a cell of a wireless network, comprising:

means for monitoring traffic among the mobile units in the cell to detect an abnormality in a cell traffic pattern;

means for determining whether the abnormality is due to the faulty mobile unit;

means for requesting registration from the mobile units in the cell if the abnormality is due to the faulty mobile unit;

means for generating a list of potentially faulty mobile units from mobile units responding to the registration request; and

means for isolating the faulty mobile unit from the list of potentially faulty mobile units.

49. A cell of a wireless network having a faulty mobile unit of a plurality of mobile units operating therein, comprising:

means for gathering information regarding traffic among the mobile units; and

means for transmitting a registration request to the mobile units to isolate the faulty mobile unit, when the information indicates a decrease in the traffic that exceeds a predetermined criteria.