Concurrent dual processing of pseudoranges with corrections

• US 9,743,373 B2
• Filed: 05/02/2014
• Issued: 08/22/2017
• Est. Priority Date: 12/28/2012
• Status: Active Grant

• Current Assignee: Trimble Inc.
• Original Assignee: Trimble Inc.
• Inventors: Rudow, Richard, Wold, Robert, Kasirajan, Venkateswaran, Talbot, Nicholas C., Loomis, Peter Van Wyck, Weisenburger, Shawn D., Janky, James M.
• Primary Examiner(s): Gregory, Bernarr
• Application Number:
  US14/268,998
• Publication Number:
  US 20140378171A1
• Time in Patent Office: 1,208 Days
• Field of Search: 340971, 340972
• CPC Class Codes: G01S 19/09 providing processing capability normally carried out by the receiver
• CPC Class Codes: G01S 19/35 Constructional details or hardware or software details of the signal processing chain
• CPC Class Codes: G01S 19/43 using carrier phase measurements, e.g. kinematic positioning; using long or short baseline interferometry
• CPC Class Codes: G01S 19/485 whereby the further system is an optical system or imaging system
• CPC Class Codes: G01S 19/49 whereby the further system is an inertial position system, e.g. loosely-coupled
• CPC Class Codes: G01S 5/16 using electromagnetic waves other than radio waves
• CPC Class Codes: H04W 4/023 using mutual or relative location information between multiple location based services [LBS] targets or of distance thresholds
• CPC Class Codes: H04W 4/027 using movement velocity, acceleration information
• CPC Class Codes: H04W 4/029 Location-based management or tracking services
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

A first process and a second process are executed concurrently by one or more hardware processors located in the cellular device and outside of a Global Navigation Satellite System (GNSS) chipset embedded in the cellular device. The first process determines a first set of one or more position fixes based on extracted raw pseudorange information. The second process determines carrier phase smoothed pseudoranges based on carrier phase information and determines a second set of one or more position fixes based on the carrier phase smoothed pseudoranges. One or more of the first set of position fixes are provided to a user while a predetermined amount of carrier phase information is not available for performing carrier phase smoothing. One or more of the second set of position fixes are provided to the user while a predetermined amount of carrier phase information is available for performing carrier phase smoothing.

Claims

1. A method of improving position determination of a cellular device, the method comprising:

extracting raw pseudorange information from a Global Navigation Satellite System (GNSS) receiver;

obtaining locally measured movement information that reflects measurements of movement of the cellular device, wherein the measurements are obtained using at least one hardware sensor that is in a known physical relationship with the cellular device;

determining, performed by a first process, a first set of one or more position fixes based on the extracted raw pseudorange information;

determining, performed by a second process, carrier phase smoothed pseudoranges by smoothing the extracted raw pseudorange information based on carrier phase information, wherein the first process and the second process are executed by at least one hardware processor, wherein the at least one hardware processor is located in the cellular device and outside of a GNSS chipset embedded in the cellular device;

determining, performed by the second process, a second set of one or more position fixes based on the carrier phase smoothed pseudoranges;

while a predetermined amount of carrier phase information is not available for performing carrier phase smoothing, providing to a user one or more of the first set of position fixes; and

while a predetermined amount of carrier phase information is available for performing carrier phase smoothing, providing to the user one or more of the second set of position fixes.

2. The method as recited by claim 1, wherein the method further comprises:

applying the locally measured movement information to the first set of position fixes and the second set of position fixes while the locally measured movement information is available.

3. The method as recited by claim 1, wherein the method further comprises:

creating blended locally measured movement information by blending locally measured movement information from two or more sensors associated with the cellular device; and

applying the blended locally measured movement information to the first set of the position fixes while the blended locally measured movement information is available.

4. The method as recited by claim 3, wherein the applying of the blended locally measured movement information further comprises:

applying the blended locally measured movement information to the first set of the position fixes and the second set of position fixes while the blended locally measured movement information is available.

5. The method as recited by claim 3, wherein the creating of the blended locally measured movement information further comprises:

blending the locally measured movement information from the sensors based on weighting factors.

6. The method as recited by claim 1, wherein the method further comprises:

determining whether to provide a position fix from the first set or the second set depending on whether a predetermined amount of carrier phase information is available, wherein a position fix is provided from the first set when a predetermined amount of carrier phase information is not available and a position fix is provided from the second set when a predetermined amount of carrier phase information is available.

7. The method as recited by claim 1, wherein the method further comprises:

obtaining external corrections from a correction source that is external to the cellular device;

providing, performed by the first process, corrected unsmoothed pseudoranges by applying the external corrections to the extracted raw pseudoranges; and

determining, performed by the first process, the first set of position fixes based on the corrected unsmoothed pseudoranges.

8. The method as recited by claim 1, wherein the method further comprises:

obtaining external corrections from a correction source that is external to the cellular device;

providing, performed by the second process, corrected smoothed pseudoranges by applying the external corrections to the carrier phase smoothed pseudoranges; and

determining, performed by the second process, the second set of position fixes based on the corrected smoothed pseudoranges.

9. A system for improving position determination of a cellular device, the system comprising:

one or more hardware processors located in the cellular device and outside of a Global Navigation Satellite System (GNSS) chipset embedded in the cellular device;

the one or more hardware processors configured to execute a first process and a second process;

extracting logic that extracts raw pseudorange information from the GNSS receiver;

locally measured movement information accessing logic that obtains locally measured movement information that reflects measurements of movement of the cellular device, wherein the measurements are obtained using at least one hardware sensor that is in a known physical relationship with the cellular device; and

processing logic that;

determines, performed by the first process, a first set of one or more position fixes based on the extracted raw pseudorange information;

determines, performed by the second process, carrier phase smoothed pseudoranges by smoothing the extracted raw pseudorange information based on carrier phase information;

determines, performed by the second process, a second set of one or more position fixes based on the carrier phase smoothed pseudoranges;

while a predetermined amount of carrier phase information is not available for performing carrier phase smoothing, provides to a user one or more of the first set of position fixes; and

while a predetermined amount of carrier phase information is available for performing carrier phase smoothing, provides to the user one or more of the second set of position fixes.

10. The system as recited by claim 9, wherein the processing logic further applies the locally measured movement information to the first set of position fixes and the second set of position fixes while the locally measured movement information is available.

11. The system as recited by claim 9, wherein the at least one hardware sensor is selected from a group consisting of a hardware sensor that is internal to the cellular device and a hardware sensor that is physically coupled to the cellular device.

12. The system as recited by claim 9, wherein the at least one hardware sensor is selected from a group consisting of an image capturing device and an accelerometer.

13. The system as recited by claim 9, wherein:

the processing logic discards at least one of the first set of position fixes based on the locally measured movement information, wherein the first process discards the at least one of the first set of position fixes based on the locally measured movement information.

14. The system as recited by claim 9, wherein:

the processing logic discards at least one of the second set of position fixes based on the locally measured movement information, wherein the second process discards the at least one of the second set of position fixes based on the locally measured movement information.

15. The system as recited by claim 9, wherein the system further comprises:

control logic that determines whether to provide a position fix from the first set or the second set depending on whether a predetermined amount of carrier phase information is available; and

position fix determining logic provides a position fix from the first set when a predetermined amount of carrier phase information is not available and a position fix is provided from the second set when a predetermined amount of carrier phase information is available.

16. The system as recited by claim 9, wherein the processing logic further:

obtains external corrections from a correction source that is external to the cellular device;

provides, performed by the first process, corrected unsmoothed pseudoranges by applying the external corrections to the extracted raw pseudoranges; and

determines, performed by the first process, the first set of position fixes based on the corrected unsmoothed pseudoranges.

17. The system as recited by claim 9, wherein the processing logic further:

obtains external corrections from a correction source that is external to the cellular device;

provides, performed by the second process, corrected smoothed pseudoranges by applying the external corrections to the carrier phase smoothed pseudoranges; and

determines, performed by the second process, the second set of position fixes based on the corrected smoothed pseudoranges.

18. The system as recited by claim 9, wherein the cellular device comprises a cellular communication enabled mobile communications device.

19. A non-transitory computer readable storage medium having computer readable instructions stored thereon for causing a computer system to perform a method of improving position determination of a cellular device using locally measured movement, the method comprising:

extracting raw pseudorange information from a Global Navigation Satellite System (GNSS) receiver;

obtaining locally measured movement information that reflects measurements of movement of the cellular device;

determining a first set of one or more position fixes based on the extracted raw pseudorange information;

determining carrier phase smoothed pseudoranges by smoothing the extracted raw pseudorange information based on carrier phase information;

determining a second set of one or more position fixes based on the carrier phase smoothed pseudoranges;

while a predetermined amount of carrier phase information is not available for performing carrier phase smoothing, providing to a user one or more of the first set of position fixes; and

while a predetermined amount of carrier phase information is available for performing carrier phase smoothing, providing to the user one or more of the second set of position fixes.

20. The non-transitory computer readable storage medium as recited by claim 19, wherein the method further comprises:

applying the locally measured movement information to the first set of position fixes and the second set of position fixes while the locally measured movement information is available.

21. The non-transitory computer readable storage medium as recited by claim 19, wherein the method further comprises:

discarding at least one of the first set of position fixes based on the locally measured movement information.

22. The non-transitory computer readable storage medium as recited by claim 19, wherein the method further comprises:

discarding at least one of the second set of position fixes based on the locally measured movement information.

23. The non-transitory computer readable storage medium as recited by claim 19, wherein the method further comprises:

determining whether to provide a position fix from the first set or the second set depending on whether a predetermined amount of carrier phase information is available, wherein a position fix is provided from the first set when a predetermined amount of carrier phase information is not available and a position fix is provided from the second set when a predetermined amount of carrier phase information is available.

24. The non-transitory computer readable storage medium as recited by claim 19, wherein the method further comprises:

obtaining external corrections from a correction source that is external to the cellular device;

providing corrected unsmoothed pseudoranges by applying the external corrections to the extracted raw pseudoranges; and

determining the first set of position fixes based on the corrected unsmoothed pseudoranges.

25. The non-transitory computer readable storage medium as recited by claim 19, wherein the method further comprises:

obtaining external corrections from a correction source that is external to the cellular device;

providing corrected smoothed pseudoranges by applying the external corrections to the carrier phase smoothed pseudoranges; and

determining the second set of position fixes based on the corrected smoothed pseudoranges.