Methods and apparatuses for selectively validating satellite positioning system measurement information

• US 8,981,992 B2
• Filed: 10/12/2009
• Issued: 03/17/2015
• Est. Priority Date: 10/12/2009
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Riley, Wyatt Thomas, Liu, Quanwei
• Primary Examiner(s): McGue, Frank J
• Application Number:
  US12/577,655
• Publication Number:
  US 20110084878A1
• Time in Patent Office: 1,982 Days
• Field of Search: 342/357.23
• US Class Current: 342/357.23
• CPC Class Codes: G01S 19/20 Integrity monitoring, fault detection or fault isolation of space segment

Abstract

Methods and apparatuses are provided that may be implemented in various electronic devices to identify suspect measurements for use in a position/velocity/time estimation filter and provide corresponding validated measurements that may be either operatively re-weighted in some manner or operatively one-sided isolated in some manner when subsequently considered by the position/velocity/time estimation filter.

Claims

1. A method of improving an estimated position/velocity/time calculation of a positioning device, comprising:

determining, by the positioning device, whether one or more electronic signals representing an initial measurement for use in a position/velocity/time estimation filter is suspect based, at least in part, on one or more electronic signals representing at least one threshold;

based on said initial measurement being determined to be suspect, establishing, by the positioning device, said initial measurement as one or more electronic signals representing a validated measurement by either;

(1) re-weighting said initial measurement with a non-zero weight; and

/or (2) one-sided isolating said initial measurement by one-sided de-weighting said initial measurement using different thresholds for positive and negative residuals; and

storing an estimated position/velocity/time calculated or updated based on said validated measurement in a memory of the positioning device.

2. The method as recited in claim 1, wherein said initial measurement is associated with at least a first signal, said first signal being received from at least one of a Satellite Positioning System (SPS), a Space Vehicle (SV), a Global Navigation Satellite System (GNSS), a Ground based transmitter (GBT), or a position, velocity, and/or time related sensor.

3. The method as recited in claim 2, wherein said initial measurement is associated with at least one of:

a signal strength of said first signal;

a type of said first signal;

a source of said first signal;

a pseudorange (PR) measurement as determined based, at least in part, using said first signal; and

/or, a pseudorange rate (PRR) measurement as determined based, at least in part, using said first signal.

4. The method as recited in claim 3, wherein said pseudorange rate (PRR) measurement is determined based, at least in part, using one or more electronic signals representing a Doppler velocity and/or carrier phase portion of said first signal.

5. The method as recited in claim 1, wherein said at least one threshold comprises at least one of one or more electronic signals representing a predetermined threshold value, one or more electronic signals representing an adaptive threshold value, and/or one or more electronic signals representing a determined probabilistic-based threshold value.

6. The method as recited in claim 1, wherein said position/velocity/time estimation filter comprises a Kalman filter.

7. The method as recited in claim 2, wherein determining whether said initial measurement is suspect comprises:

determining one or more electronic signals representing a predicted measurement for said first signal using said position/velocity/time estimation filter;

determining one or more electronic signals representing a measurement innovation based, at least in part, on said predicted measurement and said initial measurement; and

determining whether said initial measurement is suspect based, at least in part, on said measurement innovation.

8. The method as recited in claim 7, wherein determining said measurement innovation further comprises:

determining said measurement innovation based, at least in part, on one or more electronic signals representing at least one of a time updated state of said position/velocity/time estimation filter and/or at least one trial state of said position/velocity/time estimation filter.

9. The method as recited in claim 1, wherein said validated measurement comprises one or more electronic signals representing at least one of an operatively deweighted measurement or an operatively one-sided deweighted measurement as a result of operatively re-weighting said initial measurement, and further comprising:

with said position/velocity/time estimation filter, determining one or more electronic signals representing at least one of an estimated position and/or an estimated velocity based, at least in part, on one or more electronic signals representing a plurality of measurements in a measurement set, said plurality of measurements comprising said validated measurement.

10. The method as recited in claim 1, wherein said validated measurement comprises one or more electronic signals representing an operatively one-sided isolated measurement as a result of operatively one-sided isolating said initial measurement, and further comprising:

with said position/velocity/time estimation filter, determining one or more electronic signals representing at least one of an estimated position and/or an estimated velocity based, at least in part, on one or more electronic signals representing a plurality of measurements in a measurement set, but wherein said plurality of measurements do not comprise said operatively one-sided isolated measurement.

11. The method as recited in claim 1, further comprising:

with said positioning device;

based on at least one other initial measurement being determined to be suspect, operatively isolating said at least one other initial measurement by removing said at least one other initial measurement based on a minimum number of measurements remaining available.

12. An apparatus for improving an estimated position/velocity/time of a positioning device, comprising:

means for determining whether an initial measurement for use in a means for estimating position/velocity/time of the positioning device is suspect based, at least in part, on at least one threshold;

means for establishing said initial measurement as a validated measurement, based on said initial measurement being determined to be suspect, by either;

(1) re-weighting said initial measurement with a non-zero weight and/or (2) one-sided isolating said initial measurement by one-sided de-weighting said initial measurement using different thresholds for positive and negative residuals; and

means for storing an estimated position/velocity/time calculated or updated based on said validated measurement in a memory of the positioning device.

13. The apparatus as recited in claim 12, wherein said initial measurement is associated with at least a first signal, said first signal being received from at least one of a Satellite Positioning System (SPS), a Space Vehicle (SV), a Global Navigation Satellite System (GNSS), a Ground based transmitter (GBT), or a position, velocity, and/or time related sensor.

14. The apparatus as recited in claim 13, wherein said initial measurement is associated with at least one of:

a signal strength of said first signal;

a type of said first signal;

a source of said first signal;

a pseudorange (PR) measurement as determined based, at least in part, using said first signal based; and

/or, a pseudorange rate (PRR) measurement as determined based, at least in part, using said first signal.

15. The apparatus as recited in claim 14, wherein said pseudorange rate (PRR) measurement is determined based, at least in part, using a Doppler velocity and/or carrier phase portion of said first signal.

16. The apparatus as recited in claim 12, wherein said at least one threshold comprises at least one of a predetermined threshold value, an adaptive threshold value, and/or a determined probabilistic-based threshold value.

17. The apparatus as recited in claim 12, further comprising:

means for determining at least one probabilistic-based threshold.

18. The apparatus as recited in claim 13, further comprising:

means for determining a predicted measurement for said first signal;

means for determining a measurement innovation based, at least in part, on said predicted measurement and said initial measurement; and

means for determining whether said initial measurement is suspect based, at least in part, on said measurement innovation.

19. The apparatus as recited in claim 18, further comprising:

means for determining said measurement innovation based, at least in part, on at least one of a time updated state of said means for estimating position/velocity/time and/or at least one trial state of said means for estimating position/velocity/time.

20. The apparatus as recited in claim 12, wherein said validated measurement comprises at least one of an operatively deweighted measurement or an operatively one-sided deweighted measurement as a result of operatively re-weighting said initial measurement, and further comprising:

with said means for estimating position/velocity/time, determining at least one of an estimated position and/or an estimated velocity based, at least in part, on a plurality of measurements in a measurement set, said plurality of measurements comprising said validated measurement.

21. The apparatus as recited in claim 12, wherein said validated measurement comprises an operatively one-sided isolated measurement as a result of operatively one-sided isolating said initial measurement, and further comprising:

with said means for estimating position/velocity/time, determining at least one of an estimated position and/or an estimated velocity based, at least in part, on a plurality of measurements in a measurement set, but wherein said plurality of measurements do not comprise said operatively one-sided isolated measurement.

22. The apparatus as recited in claim 12, further comprising:

means for operatively isolating at least one other initial measurement by removing said at least one other initial measurement based on said at least one other initial measurement being determined to be suspect and based on a minimum number of measurements remaining available.

23. An apparatus comprising:

memory capable of storing a measurement set associated with a plurality of position/velocity/time related signals, said measurement set comprising a least an initial measurement for use in a position/velocity/time estimation filter;

at least one processing unit coupled to said memory to determine whether said initial measurement is suspect based, at least in part, on at least one threshold, and, based on said initial measurement being determined to be suspect, establish said initial measurement as a validated measurement by either;

(1) re-weighting said initial measurement with a non-zero weight; and

/or (2) one-sided isolating said initial measurement by one-sided de-weighting said initial measurement using different thresholds for positive and negative residuals, and provide said validated measurement to said memory for storage in said measurement set and subsequent use in said position/velocity/time estimation filter.

24. The apparatus as recited in claim 23, wherein said initial measurement is associated with at least a first signal, and further comprising at least one of:

a receiver coupled to at least said memory to receive at least said first signal from at least one of a Satellite Positioning System (SPS), a Space Vehicle (SV), and/or a Global Navigation Satellite System (GNSS), or a Ground based transmitter (GBT), and provide said initial measurement to said memory; and

/or

a position, velocity, and/or time related sensor coupled to at least said memory to generate said first signal and provide said initial measurement to said memory.

25. The apparatus as recited in claim 24, wherein said initial measurement is associated with at least one of:

a signal strength of said first signal;

a type of said first signal;

a source of said first signal;

a pseudorange (PR) measurement as determined based, at least in part, using said first signal based; and

/or, a pseudorange rate (PRR) measurement as determined based, at least in part, using said first signal.

26. The apparatus as recited in claim 25, wherein said pseudorange rate (PRR) measurement is determined based, at least in part, using a Doppler velocity and/or carrier phase portion of said first signal.

27. The apparatus as recited in claim 23, wherein said at least one threshold comprises at least one of a predetermined threshold value stored in said memory, and/or an adaptive threshold value and/or a probabilistic-based threshold value determined by said at least one processing unit.

28. The apparatus as recited in claim 23, further comprising a Kalman filter coupled to at least said memory to serve as said position/velocity/time estimation filter.

29. The apparatus as recited in claim 24, wherein:

said position/velocity/time estimation filter determines a predicted measurement for said first signal and a measurement innovation based, at least in part, on said predicted measurement and said initial measurement; and

said at least one processing unit determines whether said initial measurement is suspect based, at least in part, on said measurement innovation.

30. The apparatus as recited in claim 29, wherein said position/velocity/time estimation filter determines said measurement innovation based, at least in part, on at least one of a time updated state and/or at least one trial state.

31. The apparatus as recited in claim 23, wherein said validated measurement comprises at least one of an operatively deweighted measurement or an operatively one-sided deweighted measurement as a result of operatively re-weighting said initial measurement, and wherein:

said position/velocity/time estimation filter determines at least one of an estimated position and/or an estimated velocity based, at least in part, on a plurality of measurements in said measurement set, said plurality of measurements comprising said validated measurement.

32. The apparatus as recited in claim 23, wherein said validated measurement comprises an operatively one-sided isolated measurement as a result of operatively one-sided isolating said initial measurement, and wherein:

said position/velocity/time estimation filter determines at least one of an estimated position and/or an estimated velocity based, at least in part, on a plurality of measurements in said measurement set, but wherein said plurality of measurements do not comprise said operatively one-sided isolated measurement.

33. The apparatus as recited in claim 23, wherein based on at least one other initial measurement being determined to be suspect, said at least one processing unit operatively isolates said at least one other initial measurement by removing said at least one other initial measurement based on a minimum number of measurements remaining available.

34. An article for improving an estimated position/velocity/time calculation of a positioning device, comprising:

a non-transitory computer-readable medium having computer implementable instructions stored thereon that when implemented by one or more processing units in the positioning device cause the positioning device to;

determine whether an initial measurement for use in a position/velocity/time estimation filter is suspect based, at least in part, on at least one threshold;

based on said initial measurement being determined to be suspect, establish said initial measurement as a validated measurement by either;

(1) re-weighting said initial measurement with a non-zero weight; and

/or (2) one-sided isolating said initial measurement by one-sided de-weighting said initial measurement using different thresholds for positive and negative residuals; and

store an estimated position/velocity/time calculated or updated based on said validated measurement in a memory of the positioning device.

35. The article as recited in claim 34, wherein said initial measurement is associated with at least a first signal, said first signal being received from at least one of a Satellite Positioning System (SPS), a Space Vehicle (SV), a Global Navigation Satellite System (GNSS), a Ground based transmitter (GBT), or a position, velocity, and/or time related sensor.

36. The article as recited in claim 35, wherein said initial measurement is associated with at least one of:

a signal strength of said first signal;

a type of said first signal;

a source of said first signal;

a pseudorange (PR) measurement as determined based, at least in part, using said first signal based; and

/or, a pseudorange rate (PRR) measurement as determined based, at least in part, using said first signal.

37. The article as recited in claim 36, wherein said pseudorange rate (PRR) measurement is determined based, at least in part, using a Doppler velocity and/or carrier phase portion of said first signal.

38. The article as recited in claim 34, wherein said at least one threshold comprises at least one of a predetermined threshold value, an adaptive threshold value, and/or a determined probabilistic-based threshold value.

39. The article as recited in claim 34, wherein said position/velocity/time estimation filter comprises a Kalman filter.

40. The article as recited in claim 35, further comprising computer implementable instructions, which if implemented by said one or more processing units, enable the positioning device to:

determine a predicted measurement for said first signal using said position/velocity/time estimation filter;

determine a measurement innovation based, at least in part, on said predicted measurement and said initial measurement; and

determine whether said initial measurement is suspect based, at least in part, on said measurement innovation.

41. The article as recited in claim 40, further comprising computer implementable instructions, which if implemented by said one or more processing units, enable the positioning device to:

determine said measurement innovation based, at least in part, on at least one of a time updated state of said position/velocity/time estimation filter and/or at least one trial state of said position/velocity/time estimation filter.

42. The article as recited in claim 34, wherein said validated measurement comprises at least one of an operatively deweighted measurement or an operatively one-sided deweighted measurement as a result of operatively re-weighting said initial measurement, and further comprising computer implementable instructions, which if implemented by said one or more processing units, enable the positioning device to:

with said position/velocity/time estimation filter, determine at least one of an estimated position and/or an estimated velocity based, at least in part, on a plurality of measurements in a measurement set, said plurality of measurements comprising said validated measurement.

43. The article as recited in claim 34, wherein said validated measurement comprises an operatively one-sided isolated measurement as a result of operatively one-sided isolating said initial measurement, and further comprising computer implementable instructions, which if implemented by said one or more processing units, enable the positioning device to:

with said position/velocity/time estimation filter, determine at least one of an estimated position and/or an estimated velocity based, at least in part, on a plurality of measurements in a measurement set, but wherein said plurality of measurements do not comprise said operatively one-sided isolated measurement.

44. The article as recited in claim 34, further comprising computer implementable instructions, which if implemented by said one or more processing units, enable the positioning device to:

operatively isolate at least one other initial measurement by removing said at least one other initial measurement based on said at least one other initial measurement being determined to be suspect and based on a minimum number of measurements remaining available.