Method and system for location accuracy analysis

• US 6,947,734 B1
• Filed: 12/06/2002
• Issued: 09/20/2005
• Est. Priority Date: 12/06/2002
• Status: Expired due to Fees

• Current Assignee: Sprint Spectrum LP (Deutsche Telekom AG)
• Original Assignee: Sprint Spectrum LP (Deutsche Telekom AG)
• Inventors: Toubassi, Wade H.
• Primary Examiner(s): TIEU, BINH KIEN
• Application Number:
  US10/313,719
• Time in Patent Office: 1,019 Days
• Field of Search: 455/423, 455/424, 455/456.1, 455/456.5, 455/9, 455/67.11, 455/67.14, 342/419, 342/420, 342/430, 342/437, 342/445, 342/451, 342/457, 342462-463
• US Class Current: 455/423
• CPC Class Codes: G01S 5/021 Calibration, monitoring or correction G01S5/0252 takes precedence

Abstract

A wireless telecommunications network uses a wireless location technology to determine the locations of mobile stations. As part of a location accuracy analysis process, the wireless location technology is used to obtain a measured latitude and longitude for a mobile station located at a test site having a known latitude and longitude. A data analysis system calculates the radial location error, expressed as a distance, between the measured and known latitude and longitude values. The process is repeated a number of times sufficient to calculate the mean radial location error to within a predetermined uncertainty at a predetermined confidence level.

Claims

1. A method of analyzing the accuracy of a wireless location technology used in a wireless telecommunications network, said method comprising:

(a) selecting a test site, said test site having a known location;

(b) using said wireless location technology to determine a measured location for at least one mobile station located at said test site;

(c) calculating a location error between said measured location and said known location;

(d) repeating steps (b) and (c) for said at least one mobile station located at said test site to obtain n measured locations and n calculated location errors;

(e) calculating an average location error for said test site from said n calculated location errors, wherein n is sufficient to calculate said average location error to within a predetermined uncertainty at a predetermined confidence level; and

(f) storing said average location error for said test site in at least one network element of said wireless telecommunications network.

2. The method of claim 1, wherein said average location error is a mean location error.

3. The method of claim 2, wherein said n location errors are radial location errors and said mean location error is a mean radial location error.

4. The method of claim 1 further comprising:

adjusting how said wireless location technology is used so as to reduce said average location error for said test site.

5. The method of claim 1, wherein said at least one network element includes a position determining entity (PDE).

6. The method of claim 5, wherein a data analysis system performs at least steps (c) and (e).

7. The method of claim 6, wherein said data analysis system obtains said n measured locations from said PDE.

8. The method of claim 7, wherein said data analysis system obtains from said PDE said n measured locations expressed as geographic coordinates.

9. The method of claim 8, wherein said data analysis system obtains from said PDE said n measured locations expressed as latitude and longitude.

10. The method of claim 9, wherein said data analysis system calculates said n calculated location errors and said mean location error as distances.

11. The method of claim 1, further comprising:

performing steps (a) through (f) for a plurality of test sites with known locations, to obtain a plurality of average location errors stored in said at least one network element.

12. The method of claim 11, further comprising:

using said wireless location technology to determine a measured location of a mobile station located at an initially unknown location;

reporting said measured location of said mobile station to a location information consumer; and

reporting a relevant one of said stored plurality of average location errors to said location information consumer.

13. The method of claim 12, further comprising:

determining a wireless coverage area corresponding to said measured location of said mobile station; and

identifying one of said plurality of test sites as being located in said wireless coverage area, wherein said relevant average location error was obtained for said one of said plurality of test sites.

14. A system for analyzing the accuracy of a wireless location technology used in a wireless telecommunications network, said system comprising:

a position determining entity (PDE), said PDE providing a plurality of location measurements made by said wireless location technology of at least one mobile station located at a test site, said test site having a known location; and

a data analysis system communicatively coupled to said PDE, said data analysis system calculating an average location error for said test site from said plurality of location measurements and said known location of said test site.

15. The system of claim 14, wherein said average location error is a mean location error.

16. The system of claim 14, wherein said mean average location error is an average radial location error.

17. The system of claim 16, wherein said data analysis system calculates said average radial location error to within a predetermined uncertainty at a predetermined confidence level.

18. The system of claim 14, wherein said PDE provides said plurality of location measurements expressed as geographic coordinates.

19. The system of claim 18, wherein said PDE provides said plurality of location measurements expressed as latitude and longitude.

20. The system of claim 19, wherein said data analysis system calculates said average location error as a distance.