Indicating quality of GNSS position fixes

• US 9,116,231 B2
• Filed: 02/23/2012
• Issued: 08/25/2015
• Est. Priority Date: 03/11/2011
• Status: Active Grant

• Current Assignee: Trimble Navigation Limited (Trimble Inc.)
• Original Assignee: Trimble Navigation Limited (Trimble Inc.)
• Inventors: Vollath, Ulrich, Nair, Sidharth, Martinez, Jesus Michael, Price, Greg, Waterland, Glenn, Gibson, Mark
• Primary Examiner(s): LIU, HARRY K
• Application Number:
  US13/403,224
• Publication Number:
  US 20120229332A1
• Time in Patent Office: 1,279 Days
• Field of Search: 342/357.58, 342/357.45
• US Class Current: 1/1
• CPC Class Codes: G01S 19/23 Testing, monitoring, correcting or calibrating of receiver elements
• CPC Class Codes: G01S 19/41 Differential correction, e.g. DGPS [differential GPS]
• CPC Class Codes: G01S 19/43 using carrier phase measurements, e.g. kinematic positioning; using long or short baseline interferometry

Abstract

Methods and apparatus are provided for reporting quality of GNSS position fixes. A desired quality mode selection is obtained. Position fixes with respective precision estimates and satellite tracking information are obtained. For each of a plurality of position fixes a current positioning quality is determined, based on the precision estimates and satellite tracking information and quality mode selection. Current positioning quality is reported. The quality selection can be a preference of availability over accuracy, or accuracy over availability, or a balance of availability and accuracy.

Claims

1. A method of reporting quality of GNSS position fixes, comprising:

obtaining a desired GNSS positioning quality mode selection,

obtaining the GNSS position fixes, each GNSS position fix including a respective precision estimate and satellite tracking information,

determining, for each of the GNSS position fixes, a GNSS positioning quality based on the precision estimate, the satellite tracking information, and the GNSS positioning quality mode selection, and

reporting the GNSS positioning quality.

2. The method of claim 1, wherein the GNSS positioning quality mode selection comprises a preference of availability over accuracy, or accuracy over availability, or a balance of availability and accuracy.

3. The method of claim 2, wherein obtaining the GNSS position fixes comprises processing GNSS receiver data subject to at least one control favoring the preference.

4. The method of claim 3, wherein the at least one control favoring the preference comprises at least one of:

a satellite elevation mask, a C/No (Carrier-to-Noise power ratio) mask, a DOP (Dilution of Precision) mask, a control providing additional accuracy, and a control providing additional availability.

5. The method of claim 1, wherein the precision estimate for each GNSS position fix is determined from covariances of parameters estimated with the GNSS position fix.

6. The method of claim 1, wherein determining the GNSS positioning quality comprises at least one of:

determining whether satellites are being tracked, determining whether a GNSS position fix is being determined, determining whether availability exceeds a threshold, determining whether availability and accuracy are balanced, and determining whether accuracy exceeds a threshold.

7. The method of claim 1, wherein reporting the GNSS positioning quality comprises displaying at least one of:

an icon indicating the GNSS positioning quality, a color indicating the GNSS positioning quality, a number of bars indicating whether criteria corresponding to the desired GNSS positioning quality mode selection are satisfied.

8. The method of claim 7, wherein reporting the GNSS positioning quality comprises displaying an indication of the desired GNSS positioning quality mode selection.

9. An article of manufacture comprising a computer-readable storage device embodying instructions which enable a processor to perform the method according to claim 1.

10. Apparatus for reporting quality of GNSS position fixes, comprising:

a memory storing a desired GNSS positioning quality mode selection,

a memory storing the GNSS position fixes, each GNSS position fix including a respective precision estimate and satellite tracking information,

a processing element to determine, for each of the GNSS position fixes, a GNSS positioning quality based on the precision estimate, the satellite tracking information, and the GNSS positioning quality mode selection, and

a reporting element to report the GNSS positioning quality.

11. The apparatus of claim 10, wherein the GNSS positioning quality mode selection comprises a preference of availability over accuracy, or accuracy over availability, or a balance of availability and accuracy.

12. The apparatus of claim 11, wherein the GNSS position fixes are determined from processing of GNSS receiver data subject to at least one control favoring the preference.

13. The apparatus of claim 12, wherein the at least one control favoring the preference comprises at least one of:

a satellite elevation mask, a C/No (Carrier-to-Noise power ratio) mask, a DOP (Dilution of Precision) mask, a control providing additional accuracy, and a control providing additional availability.

15. The apparatus of claim 10, wherein the processing element determines the GNSS positioning quality based on at least one of:

whether satellites are being tracked, whether a GNSS position fix is being determined, whether availability exceeds a threshold, whether availability and accuracy are balanced, and whether accuracy exceeds a threshold.

16. The apparatus of claim 10, wherein the reporting element displays at least one of:

an icon indicating the GNSS positioning quality, a color indicating the GNSS positioning quality, a number of bars indicating whether criteria corresponding to the desired GNSS positioning quality mode selection are satisfied.

17. The apparatus of claim 16, wherein the reporting element displays an indication of the desired GNSS positioning quality mode selection.

14. An apparatus for reporting quality of GNSS position fixes, comprising:

a memory storing a desired quality mode selection,

a memory storing position fixes with respective precision estimates and satellite tracking information,

a processing element to determine for each of a plurality of position fixes a current positioning quality based on the precision estimates and satellite tracking information and quality mode selection, and

a reporting element to report current positioning quality,

wherein the quality selection comprises a preference of availability over accuracy, or accuracy over availability, or a balance of availability and accuracy,

wherein the position fixes are determined from processing of GNSS receiver data subject to at least one control favoring the preference,

wherein the position fixes are determined from processing of GNSS receiver data subject to at least one control favoring the preference,

wherein the at least one control favoring the preference comprises at least one of;

a satellite elevation mask, a C/No (Carrier-to-Noise power ratio) mask, a DOP (Dilution of Precision) mask, a control providing additional accuracy, and a control providing additional availability, and

wherein the precision estimate for each position fix is determined from covariances of parameters estimated with the position fix.