Hybrid RTK

• US 10,408,944 B2
• Filed: 01/27/2017
• Issued: 09/10/2019
• Est. Priority Date: 01/29/2016
• Status: Active Grant

• Current Assignee: Javad GNSS, Inc.
• Original Assignee: Javad GNSS, Inc.
• Inventors: Ashjaee, Javad
• Primary Examiner(s): Akonai, Olumide Ajibade
• Application Number:
  US15/418,474
• Publication Number:
  US 20170219715A1
• Time in Patent Office: 956 Days
• CPC Class Codes: G01S 19/05 providing aiding data
• CPC Class Codes: G01S 19/09 providing processing capability normally carried out by the receiver
• CPC Class Codes: G01S 19/258 relating to the satellite constellation, e.g. almanac, ephemeris data, lists of satellites in view
• CPC Class Codes: G01S 19/40 Correcting position, velocity or attitude
• CPC Class Codes: G01S 19/41 Differential correction, e.g. DGPS [differential GPS]
• CPC Class Codes: G01S 19/426 by combining or switching between position solutions or signals derived from different modes of operation in a single system
• CPC Class Codes: G01S 19/43 using carrier phase measurements, e.g. kinematic positioning; using long or short baseline interferometry

Abstract

A GNSS device includes an antenna configured to receive a first plurality of GNSS signals from a first plurality of GNSS satellites and a second plurality of GNSS signals from a second plurality of GNSS satellites. The GNSS device also includes a communications interface configured to receive correction signals from a GNSS base unit. A processor of the GNSS device is coupled to the antenna and communications interface for processing data from the first plurality of GNSS signals and the second plurality of GNSS signals. Memory of the GNSS device includes executable instructions for several steps. A first algorithm is executed to determine first position data for the GNSS device based on the first plurality of GNSS signals and a correction signal received at the GNSS device from the GNSS base unit. The first position data is stored memory of the GNSS device. A second algorithm is executed to determine second position data for the GNSS device based on the second plurality of GNSS signals. In response to the second algorithm failing to determine the second position data, GNSS signal data is stored in memory of the GNSS device. The GNSS signal data is based on the second plurality of GNSS signals. The GNSS signal data are transmitted to an external device.

Claims

1. A method of determining positions of a global navigation satellite system (GNSS) device, the method comprising:

receiving, at the GNSS device, a first plurality of GNSS signals from a first plurality of GNSS satellites;

receiving, at the GNSS device, a first correction signal from a GNSS base unit;

executing, on the GNSS device, a first algorithm to determine first position data for the GNSS device based on the first plurality of GNSS signals and the first correction signal;

storing the first position data in memory of the GNSS device;

receiving, at the GNSS device, a second plurality of GNSS signals from a second plurality of GNSS satellites;

executing, on the GNSS device, a second algorithm to determine second position data for the GNSS device based on the second plurality of GNSS signals;

after determining that the second algorithm fails to determine the second position data, storing GNSS signal data in memory of the GNSS device, wherein the GNSS signal data is based on the second plurality of GNSS signals and data received from the GNSS base unit;

transmitting the GNSS signal data to a server for processing;

calculating, at the server, a second correction signal, based on the GNSS signal data; and

determining the second position data for the GNSS device based on the second plurality of GNSS signals and the second correction signal.

2. The method of claim 1 further comprising:

receiving position data based on the GNSS signal data from the server.

3. The method of claim 1 further comprising:

storing data from the GNSS base unit as GNSS signal data.

4. The method of claim 1, wherein the GNSS base unit is a virtual base unit or a reference base station.

5. The method of claim 1, wherein executing the second algorithm does not involve the second algorithm using a correction signal received from the GNSS base unit.

6. The method of claim 1, wherein the first algorithm and the second algorithm are the same algorithm and executing the second algorithm includes providing data from the second plurality of GNSS signals to the first algorithm while the first algorithm is running.

7. The method of claim 1, wherein the first position data is based on a fixed position, and wherein executing a second algorithm to determine the second position data results in determining third position data that is based on a float position.

8. The method of claim 1 further comprising:

determining whether the second algorithm was successful in determining the second position data based on a set of tolerances.

9. The method of claim 1 further comprising:

in response to the second position data not being determined, displaying a prompt on a display of the GNSS device, wherein the prompt allows a user to select a first option or a second option, and wherein the first option causes the storing of the GNSS signal data in memory of the GNSS device and the second option causes the operation of the GNSS device to continue without storing the GNSS signal data.

10. The method of claim 1 further comprising:

determining whether the second algorithm has failed to determine the second position data based on the second algorithm executing for a time equal to or longer than a threshold amount of time.

11. A non-transitory computer readable storage medium encoded with a program for determining a position of a GNSS device, the program comprising instructions for:

executing, on the GNSS device, a first algorithm to determine first position data for the GNSS device based on a first plurality of GNSS signals received at the GNSS device from a first plurality of GNSS satellites and a first correction signal received at the GNSS device from a GNSS base unit;

storing the first position data in memory of the GNSS device;

executing, on the GNSS device, a second algorithm to determine second position data for the GNSS device based on a second plurality of GNSS signals receive at the GNSS device from a second plurality of GNSS satellites; and

after determining that the second algorithm fails to determine the second position data, storing GNSS signal data in memory of the GNSS device, wherein the GNSS signal data is based on the second plurality of GNSS signals and data received from the GNSS base unit;

transmitting the GNSS signal data to an external device for processing;

calculating, at the external device, a second correction signal, based on the GNSS signal data; and

determining the second position data for the GNSS device based on the second plurality of GNSS signals and the second corrections signal.

12. The non-transitory computer readable storage medium of claim 11, the program further comprising instructions for:

receiving position data based on the GNSS signal data from the external device.

13. The non-transitory computer readable storage medium of claim 11, the program further comprising instructions for:

storing data from the GNSS base unit as GNSS signal data.

14. The non-transitory computer readable storage medium of claim 11, wherein the GNSS base unit is a virtual base unit or a reference base station.

15. The non-transitory computer readable storage medium of claim 11, wherein executing the second algorithm does not involve the second algorithm using a correction signal received from the GNSS base unit.

16. The non-transitory computer readable storage medium of claim 11, wherein the first algorithm and the second algorithm are the same algorithm and executing the second algorithm includes providing data from the second plurality of GNSS signals to the first algorithm while the first algorithm is running.

17. The non-transitory computer readable storage medium of claim 11, wherein the first position data is based on a fixed position, and wherein executing a second algorithm to determine the second position data results in determining third position data that is based on a float position.

18. The non-transitory computer readable storage medium of claim 11, the program further comprising instructions for:

determining whether the second algorithm was successful in determining the second position data based on a set of tolerances.

19. The non-transitory computer readable storage medium of claim 11, the program further comprising instructions for:

in response to the second position data not being determined, displaying a prompt on a display of the GNSS device, wherein the prompt allows a user to select a first option or a second option, and wherein the first option causes the storing of the GNSS signal data in memory of the GNSS device and the second option causes the operation of the GNSS device to continue without storing the GNSS signal data.

20. The non-transitory computer readable storage medium of claim 11, the program further comprising instructions for:

determining whether the second algorithm has failed to determine the second position data based on the second algorithm executing for a time equal to or longer than a threshold amount of time.

21. A GNSS system comprising:

an antenna configured to receive a first plurality of GNSS signals from a first plurality of GNSS satellites and a second plurality of GNSS signals from a second plurality of GNSS satellites;

a communications interface configured to receive correction signals from a GNSS base unit;

a processor coupled to the antenna and communications interface for processing data from the first plurality of GNSS signals and the second plurality of GNSS signals;

an external device;

memory storing processor executable instructions for;

executing, on the GNSS device, a first algorithm to determine first position data for the GNSS device based on the first plurality of GNSS signals and a first correction signal received at the GNSS device from the GNSS base unit;

storing the first position data in memory of the GNSS device;

executing, on the GNSS device, a second algorithm to determine second position data for the GNSS device based on the second plurality of GNSS signals; and

in response to the second algorithm failing to determine the second position data, storing GNSS signal data in memory of the GNSS device, wherein the GNSS signal data is based on the second plurality of GNSS signals; and

transmitting the GNSS signal data to the external device;

calculating, at the external device, a second corrections signal, based on the GNSS signal data; and

determining the second position data for the GNSS device based on the second plurality of GNSS signals and the second correction signal.

22. The GNSS system of claim 21, the memory further comprising processor executable instructions for:

receiving position data based on the GNSS signal data from the external device.

23. The GNSS system of claim 21, the memory further comprising processor executable instructions for:

storing data from the GNSS base unit as GNSS signal data.

24. The GNSS system of claim 21, wherein the GNSS base unit is a virtual base unit or a reference base station.

25. The GNSS system of claim 21, wherein executing the second algorithm does not involve the second algorithm using a correction signal received from the GNSS base unit.

26. The GNSS system of claim 21, wherein the first algorithm and the second algorithm are the same algorithm and executing the second algorithm includes providing data from the second plurality of GNSS signals to the first algorithm while the first algorithm is running.

27. The GNSS system of claim 21, wherein the first position data is based on a fixed position, and wherein executing a second algorithm to determine the second position data results in determining third position data that is based on a float position.

28. The GNSS system of claim 21, the memory further comprising processor executable instructions for:

determining whether the second algorithm was successful in determining the second position data based on a set of tolerances.

29. The GNSS system of claim 21, the memory further comprising processor executable instructions for:

in response to the second position data not being determined, displaying a prompt on a display of the GNSS device, wherein the prompt allows a user to select a first option or a second option, and wherein the first option causes the storing of the GNSS signal data in memory of the GNSS device and the second option causes the operation of the GNSS device to continue without storing the GNSS signal data.

30. The GNSS system of claim 21, the memory further comprising processor executable instructions for:

determining whether the second algorithm has failed to determine the second position data based on the second algorithm executing for a time equal to or longer than a threshold amount of time.