Method and system for determining cell-sector location parameters based on neighbor status

• US 9,020,531 B1
• Filed: 05/24/2012
• Issued: 04/28/2015
• Est. Priority Date: 05/24/2012
• Status: Active Grant

• Current Assignee: Sprint Spectrum LLC (Deutsche Telekom AG)
• Original Assignee: Sprint Spectrum LP (Deutsche Telekom AG)
• Inventors: McMullen, Michael P., Nelson, Rodney D., Wilson, Benjamin
• Primary Examiner(s): VIANA DI PRISCO, GERMAN
• Application Number:
  US13/479,808
• Time in Patent Office: 1,069 Days
• Field of Search: None
• US Class Current: 455/456.2
• CPC Class Codes: G01S 5/011 Identifying the radio environment
• CPC Class Codes: G01S 5/021 Calibration, monitoring or correction G01S5/0252 takes precedence
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 64/003 locating network equipment

Abstract

Location information may be provided for a mobile station based on the serving area that is currently serving the mobile station. The location information may include a representative location (e.g., a centroid location of the serving area) and an uncertainty (e.g., a distance between the representative location and a boundary of the serving area). The representative location and uncertainty for a serving area may depend on the status of at least one neighboring area. For example, the effective size of a serving area may become larger when a neighboring area is heavily loaded or out of service. In an embodiment, a location server receives a request to locate a mobile station, selects a representative location and uncertainty for the serving area that is serving the mobile station based on the status of at least one neighboring area, and reports the representative location and uncertainty in response to the request.

Claims

1. A method, comprising:

receiving from a requestor a request to locate a mobile station;

determining that said mobile station is served by a serving area of a wireless network, wherein said serving area is a wireless coverage area defined by a serving base station;

identifying at least one neighboring area in said wireless network;

determining a status of said at least one neighboring area from among at least three different status types, the three different status types including a default status, a loaded status, and an out-of-service status;

selecting a representative location and an uncertainty based, at least in part, on said serving area and said status of said at least one neighboring area, wherein said selecting comprises;

in response to said at least one neighboring area having said default status, selecting a first representative location and a first uncertainty;

in response to said at least one neighboring area having said loaded status, selecting a second representative location and a second uncertainty; and

in response to said at least one neighboring area having said out-of-service status, selecting a third representative location and a third uncertainty; and

reporting said representative location and uncertainty to said requestor in response to said request.

2. The method of claim 1, wherein said serving area and said at least one neighboring areas are cell-sectors.

3. The method of claim 1, wherein identifying at least one neighboring area in said wireless network comprises:

determining that said serving area is associated with an azimuthal range defined by said serving base station;

identifying at least one base station located within said azimuthal range; and

identifying one or more wireless coverage areas defined by said at least one base station as said at least one neighboring area.

4. The method of claim 1, wherein determining a status of said at least one neighboring area comprises determining whether said at least one neighboring area is in service or out of service.

5. The method of claim 1, wherein determining a status of said at least one neighboring area comprises determining a load level of said at least one neighboring area.

6. The method of claim 1, wherein selecting a representative location and an uncertainty based, at least in part, on said serving area and said status of said at least one neighboring area comprises:

estimating a geographic extent of said serving area based on said status of said at least one neighboring area;

selecting said representative location based on said estimated geographic extent of said serving area; and

selecting said uncertainty based on said estimated geographic extent of said serving area.

7. The method of claim 6, wherein selecting said representative location based on said estimated geographic extent of said serving area comprises:

determining a centroid location in said estimated geographic extent of said serving area; and

selecting said representative location based on said centroid location.

8. The method of claim 6, wherein selecting said uncertainty based on said estimated geographic extent of said serving area comprises:

determining an estimated boundary defining said estimated geographic extent of said serving area;

determining a maximum distance between said representative location and said estimated boundary; and

selecting said uncertainty based on said maximum distance.

9. The method of claim 6, wherein estimating a geographic extent of said serving area based on said status of said at least one neighboring area comprises:

selecting a radius based on said status of said at least one neighboring area; and

estimating said geographic extent of said serving area as a sector of a circle centered at said serving base station, wherein said circle has said selected radius.

10. The method of claim 9, wherein said selected radius has (i) a first length when said at least one neighboring area has said default status, (ii) a second length when said at least one neighboring area has said loaded status, and (iii) a third length when said at least one neighboring area has said out-of-service status.

11. The method of claim 10, wherein said at least one neighboring area is defined by a neighboring base station, wherein said neighboring base station has a separation distance from said serving base station, and wherein said first length is less than said separation distance.

12. The method of claim 11, wherein said second length is approximately equal to said separation distance.

13. The method of claim 11, wherein said third length is greater than said separation distance.

14. A system comprising:

a processor;

data storage; and

program instructions stored in said data storage, wherein said program instructions are executable by said processor to cause said system to perform functions, said functions comprising;

receiving a request to locate a mobile station;

determining that said mobile station is served by a serving area of a wireless network, wherein said serving area is a wireless coverage area defined by a serving base station;

identifying at least one neighboring area in said wireless network;

determining a status of said at least one neighboring area from among at least three different status types, the three different status types including a default status, a loaded status, and an out-of-service status;

selecting a representative location and an uncertainty based, at least in part, on said serving area and said status of said at least one neighboring area, wherein said selecting comprises;

in response to said at least one neighboring area having said default status, selecting a first representative location and a first uncertainty;

in response to said at least one neighboring area having said loaded status, selecting a second representative location and a second uncertainty; and

in response to said at least one neighboring area having said out-of-service status, selecting a third representative location and a third uncertainty; and

reporting said representative location and uncertainty to said requestor in response to said request.

15. The system of claim 14, wherein determining a status of said at least one neighboring area comprises querying at least one element of said wireless network.

16. The system of claim 15, wherein said at least one element of said wireless network comprises a base station controller (BSC).

17. The system of claim 14, wherein said second representative location has a greater distance from said serving base station than that of said first representative location, and wherein second uncertainty is greater than said first uncertainty.

18. The system of claim 17, wherein said third representative location has a greater distance from said serving base station than that of said second representative location, and wherein third uncertainty is greater than said second uncertainty.