Method and apparatus for processing navigation data in position determination

• US 7,446,706 B2
• Filed: 12/07/2006
• Issued: 11/04/2008
• Est. Priority Date: 02/14/2003
• Status: Expired due to Term

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Patrick, Christopher, Riley, Wyatt T.
• Primary Examiner(s): Issing; Gregory C
• Application Number:
  US11/608,163
• Publication Number:
  US 20070109192A1
• Time in Patent Office: 698 Days
• Field of Search: 342/451, 342/450, 342/357.02
• US Class Current: 342/450
• 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 plurality of measurements for position determination for the mobile station from position determination signals received at the mobile station;

estimating a probability that each of the plurality of measurements is a false alarm to produce a plurality of probability estimates before determining a consistency among the plurality of measurements;

determining a reliability indicator for each of the plurality of probability estimates to produce a plurality of reliability indicators;

combining the plurality of reliability indicators to determine a reliability level of a position determined for the mobile station using the plurality of measurements; and

determining whether to eliminate at least one of the plurality of measurements using at least one of the plurality of reliability indicators in response to determining the consistency among the plurality of measurements.

2. The method of claim 1, further comprising:

calculating the position for the mobile station using the plurality of measurements.

3. The method of claim 1, wherein each of the plurality of reliability indicators is a value of more than two levels.

4. The method of claim 3, wherein each of the plurality of reliability indicators is a number within a range.

5. The method of claim 1, further comprising:

determining one of the plurality of reliability indicators from one or more signal quality indicators;

wherein the one or more signal quality indicators comprises one of;

a) magnitude of a correlation peak;

b) correlation peak shape indicator;

c) signal strength;

d) signal to noise ratio; and

e) signal to interference ratio.

6. 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 plurality of measurements for positlon determination for the mobile station from position determination signals received at the mobile station;

estimating a probability that each of the plurality of measurements is a false alarm to produce a plurality of probability estimates before determining a consistency among the plurality of measurements;

determining a reliability indicator for each of the plurality of probability estimates to produce a plurality of reliability indicators;

combining the plurality of reliability indicators to determine a reliability level of a position determined for the mobile station using the plurality of measurements; and

determining whether to eliminate at least one of the plurality of measurements using at least one of the plurality of reliability indicators in response to determining the consistency among the plurality of measurements.

7. The medium of claim 6, wherein the method further comprises:

calculating the position for the mobile station using the plurality of measurements.

8. The medium of claim 6, wherein each of the plurality of reliability indicators is a value of more than two levels.

9. The medium of claim 8, wherein each of the plurality of reliability indicators is a number within a range.

10. The medium of claim 6, wherein the method further comprises:

determining one of the plurality of reliability indicators from one or more signal quality indicators;

wherein the one or more signal quality indicators comprises one of;

a) magnitude of a correlation peak;

b) correlation peak shape indicator;

c) signal strength;

d) signal to noise ratio; and

e) signal to interference ratio.

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

means for determining a plurality of measurements for position determination for the mobile station from position determination signals received at the mobile station;

means for estimating a probability that each of the plurality of measurements is a false alarm to produce a plurality of probability estimates before determining a consistency among the plurality of measurements;

means for determining a reliability indicator for each of the plurality of probability estimates to produce a plurality of reliability indicators;

means for combining the plurality of reliability indicators to determine a reliability level of a position determined for the mobile station using the plurality of measurements; and

means for determining whether to eliminate at least one of the plurality of measurements using at least one of the plurality of reliability indicators in response to determining the consistency among the plurality of measurements.

12. The data processing system of claim 11, further comprising:

means for calculating the position for the mobile station using the plurality of measurements.

13. The data processing system of claim 11, wherein each of the plurality of reliability indicators is a value of more than two levels.

14. The data processing system of claim 13, wherein each of the plurality of reliability indicators is a number within a range.

15. The data processing system of claim 11, further comprising:

means for determining one of the plurality of reliability indicators from one or more signal quality indicators;

wherein the one or more signal quality indicators comprises one of;

a) magnitude of a correlation peak;

b) correlation peak shape indicator;

c) signal strength;

d) signal to noise ratio; and

e) signal to interference ratio.

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

a memory to store a plurality of measurements, a plurality of probability estimates, and a plurality of reliability indicators; and

a processor coupled to the memory, the processor

determining a plurality of measurements for position determination for the mobile station from position determination signals received at the mobile station;

estimating a probability that each of the plurality of measurements is a false alarm to produce a plurality of probability estimates before determining a consistency among the plurality of measurements;

determining a reliability indicator for each of the plurality of probability estimates to produce a plurality of reliability indicators;

combining the plurality of reliability indicators to determine a reliability level of a position determined for the mobile station using the plurality of measurements; and

determining whether to eliminate at least one of the plurality of measurements using at least one of the plurality of reliability indicators in response to determining the consistency among the plurality of measurements.

17. The data processing system of claim 16, wherein the processor further calculates the position for the mobile station using the plurality of measurements.

18. The data processing system of claim 16, wherein each of the plurality of reliability indicators is a value of more than two levels.

19. The data processing system of claim 18, wherein each of the plurality of reliability indicators is a number within a range.

20. The data processing system of claim 16, wherein the processor further detennines one of the plurality of reliability indicators from one or more signal quality indicators;

wherein the one or more signal quality indicators comprises one of;

a) magnitude of a correlation peak;

b) correlation peak shape indicator;

c) signal strength;

d) signal to noise ratio; and

e) signal to interference ratio.