Method and apparatus for processing navigation data in position determination

• US 7,170,447 B2
• Filed: 10/20/2003
• Issued: 01/30/2007
• Est. Priority Date: 02/14/2003
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Patrick, Christopher, Riley, Wyatt T.
• Primary Examiner(s): Issing; Gregory C.
• Application Number:
  US10/690,175
• Publication Number:
  US 20040160365A1
• Time in Patent Office: 1,198 Days
• Field of Search: 342/451, 342/357.02
• US Class Current: 342/451
• CPC Class Codes: G01S 19/396 Determining accuracy or reliability of position or pseudorange measurements
• CPC Class Codes: G01S 5/0221 Receivers
• CPC Class Codes: G01S 5/0244 Accuracy or reliability of position solution or of measurements contributing thereto
• CPC Class Codes: G01S 5/0278 involving statistical or probabilistic considerations G01S5/0252, G01S5/0294 take precedence

Abstract

Methods and apparatuses for the processing of false alarms in position determination. At least one embodiment of the present invention estimates and uses measurement false alarm probabilities in the position determination process. In one embodiment, the estimated measurement false alarm probabilities are combined to determine the reliability of the determined position solution or the reliability of the set of measurements as a collection. In one embodiment, the estimated measurement false alarm probabilities are used in the isolation and elimination of faulty measurements. For example, the traditional geometry based metric for identifying a faulty measurement is further weighted according to the measurement false alarm probabilities in order to determine the faulty measurement.

Claims

1. A method of position determination for a mobile station, the method comprising:

determining a first measurement for position determination for the mobile station from position determination signals received at the mobile station; and

estimating a probability that the first measurement is a false alarm from the position determination signals to determine a first reliability indicator for the first measurement.

2. The method of claim 1, further comprising:

determining a reliability level from the first reliability indicator to represent a probability that a position for the mobile station calculated using the first measurement is not false.

3. The method of claim 2, wherein the position is calculated at the mobile station.

4. The method of claim 1, further comprising:

transmitting the first measurement and the first reliability indicator to a remote server for position determination of the mobile station.

5. The method of claim 1, further comprising:

transmitting one or more signal quality indicators from the mobile station to a remote server, the one or more signal quality indicators being determined from the position determination signals for the first measurement;

wherein the first reliability indicator is determined at the remote server using the one or more signal quality indicators.

6. The method of claim 1, further comprising:

determining a second measurement far position determination for the mobile station from position determination signals received at the mobile station; and

estimating a probability that the second measurement is a false alarm from the position determination signals to determine a second reliability indicator for the second measurement.

7. The method of claim 6, further comprising:

calculating a position solution for the mobile station using the first and second measurements; and

combining the first and second reliability indicators to determine a reliability of the position solution.

8. The method of claim 6, further comprising:

eliminating one of the first and second measurements from position determination using the first and second reliability indicators.

9. The method of claim 1, wherein the first reliability indicator is determined from at least one of:

a) magnitude of a correlation peak;

b) correlation peak width;

c) signal strength;

d) signal to noise ratio;

e) signal to interference ratio;

f) relationship of a correlation peak used for determination of the first measurement with one or more candidate peaks; and

g) relationship of signals for determination of the first measurement with detected signals.

10. The method of claim 1, wherein the first measurement comprises one of:

a) a time of arrival of a signal; and

b) a pseudorange.

11. A machine readable medium containing executable computer program instructions which when executed by a data processing system cause the system to perform a method of position determination for a mobile station, the method comprising:

determining a first measurement for position determination for the mobile station from position determination signals received at the mobile station; and

estimating a probability that the first measurement is a false alarm from the position determination signals to determine a first reliability indicator for the first measurement.

12. The medium of claim 11, wherein the method further comprises:

determining a reliability level from the first reliability indicator to represent a probability that a position for the mobile station calculated using the first measurement is not false.

13. The medium of claim 12, wherein the position is calculated at the mobile station.

14. The medium of claim 11, wherein the method further comprises:

transmitting the first measurement and the first reliability indicator to a remote server for position determination of the mobile station.

15. The medium of claim 11, wherein the method further comprises:

transmitting one or more signal quality indicators from the mobile station to a remote server, the one or more signal quality indicators being determined from the position determination signals for the first measurement;

wherein the first reliability indicator is determined at the remote server using the one or more signal quality indicators.

16. The medium of claim 11, wherein the method further comprises:

determining a second measurement for position determination for the mobile station from position determination signals received at the mobile station; and

estimating a probability that the second measurement is a false alarm from the position determination signals to determine a second reliability indicator for the second measurement.

17. The medium of claim 16, wherein the method further comprises:

calculating a position solution for the mobile station using the first and second measurements; and

combining the first and second reliability indicators to determine a reliability of the position solution.

18. The medium of claim 16, wherein the method further comprises:

eliminating one of the first and second measurements from position determination using the first and second reliability indicators.

19. The medium of claim 11, wherein the first reliability indicator is determined from at least one of:

a) magnitude of a correlation peak;

b) correlation peak width;

c) signal strength;

d) signal to noise ratio;

e) signal to interference ratio;

f) relationship of a correlation peak used for determination of the first measurement with one or more candidate peaks; and

g) relationship of signals for determination of the first measurement with detected signals.

20. The medium of claim 11, wherein the first measurement comprises one of:

a) a time of arrival of a signal; and

b) a pseudorange.

21. A data processing system for position determination for a mobile station, the data processing system comprising:

means for determining a first measurement for position determination for the mobile station from position determination signals received at the mobile station; and

means for estimating a probability that the first measurement is a false alarm from the position determination signals to determine a first reliability indicator for the first measurement.

22. The data processing system of claim 21, further comprising:

means for determining a reliability level from the first reliability indicator to represent a probability that a position for the mobile station calculated using the first measurement is not false.

23. The data processing system of claim 22, wherein the position is calculated at the mobile station.

24. The data processing system of claim 21, further comprising:

means for transmitting the first measurement and the first reliability indicator to a remote server for position determination of the mobile station.

25. The data processing system of claim 21, further comprising:

means for transmitting one or more signal quality indicators from the mobile station to a remote server, the one or more signal quality indicators being determined from the position determination signals for the first measurement;

wherein the first reliability indicator is determined at the remote server using the one or more signal quality indicators.

26. The data processing system of claim 21, further comprising:

means for determining a second measurement for position determination for the mobile station from position determination signals received at the mobile station; and

means for estimating a probability that the second measurement is a false alarm from the position determination signals to determine a second reliability indicator for the second measurement.

27. The data processing system of claim 26, further comprising:

means for calculating a position solution for the mobile station using the first and second measurements; and

means for combining the first and second reliability indicators to determine a reliability of the position solution.

28. The data processing system of claim 26, further comprising:

means for eliminating one of the first and second measurements from position determination using the first and second reliability indicators.

29. The data processing system of claim 21, wherein the first reliability indicator is determined from at least one of:

a) magnitude of a correlation peak;

b) correlation peak width;

c) signal strength;

d) signal to noise ratio;

e) signal to interference ratio;

f) relationship of a correlation peak used for determination of the first measurement with one or more candidate peaks; and

g) relationship of signals for determination of the first measurement with detected signals.

30. The data processing system of claim 21, wherein the first measurement comprises one of:

a) a time of arrival of a signal; and

b) a pseudorange.

31. A mobile station of a position determination system, the mobile station comprising:

a signal receiving circuit to receive position determination signals;

a processor coupled to the signal receiving circuit, the processor determining a first measurement for position determination for the mobile station from the position determination signals received at the mobile station, the processor estimating a probability that the first measurement is a false alarm from the position determination signals to determine a first reliability indicator for the first measurement.

32. The mobile station of claim 31, wherein the processor further determines a reliability level from the first reliability indicator to represent a probability that a position for the mobile station calculated using the first measurement is not false.

33. The mobile station of claim 31, further comprising:

a communication section coupled to the processor, the communication section transmitting the first measurement and the first reliability indicator to a remote server for position determination of the mobile station.

34. The mobile station of claim 31, wherein the processor further determines a second measurement for position determination for the mobile station from position determination signals received at the mobile station, and estimates a probability that the second measurement is a false alarm from the position determination signals to determine a second reliability indicator for the second measurement.

35. The mobile station of claim 34, wherein the processor further calculates a position solution for the mobile station using the first and second measurements and combines the first and second reliability indicators to determine a reliability of the position solution.

36. The mobile station of claim 34, wherein the processor further eliminates one of the first and second measurements from position determination using the first and second reliability indicators.

37. The mobile station of claim 31, wherein the first reliability indicator is determined from at least one of:

a) magnitude of a correlation peak;

b) correlation peak width;

c) signal strength;

d) signal to noise ratio;

e) signal to interference ratio;

f) relationship of a correlation peak used for determination of the first measurement with one or more candidate peaks; and

g) relationship of signals for determination of the first measurement with detected signals.

38. The mobile station of claim 31, wherein the first measurement comprises one of:

a) a time of arrival of a signal; and

b) a pseudorange.