Method for combined use of a local positioning system, a local RTK system, and a regional, wide-area, or global carrier-phase positioning system

• US 20060152407A1
• Filed: 01/31/2006
• Published: 07/13/2006
• Est. Priority Date: 01/13/2004
• Status: Active Grant

• Current Assignee: Deere & Company
• Original Assignee: Navcom Technology, Inc. (Deere & Company)
• Inventors: Hatch, Ronald R., Stephens, Scott Adam
• Granted Patent: US 7,511,661 B2
• Time in Patent Office: Days
• US Class Current: 342/357.310
• CPC Class Codes: G01S 19/41 Differential correction, e.g. DGPS [differential GPS]
• CPC Class Codes: G01S 19/44 Carrier phase ambiguity resolution; Floating ambiguity; LAMBDA [Least-squares AMBiguity Decorrelation Adjustment] method

Abstract

The present invention includes a method for a combined use of a local positioning system, a local RTK system and a regional, wide-area, or global differential carrier-phase positioning system (WADGPS) in which disadvantages associated with the local positioning system, the RTK and the WADGPS navigation techniques when used separately are avoided. The method includes using a known position of a user receiver that has been stationary or using an RTK system to initialize the floating ambiguity values in the WADGPS system when the user receiver is moving. Thereafter, the refraction-corrected carrier-phase measurements obtained at the user GPS receiver are adjusted by including the corresponding initial floating ambiguity values and the floating ambiguity values are treated as well known (small variance) in subsequent processes to position the user receiver in the WADGPS system.

Claims

1. A method for positioning or navigating an object associated with both a local positioning system and a wide-area differential satellite positioning system, comprising:

determining a first position of the object in accordance with carrier-phase measurements using the wide-area differential satellite positioning system in a first mode of operation; and

determining a second position of the object in accordance with information received from the local positioning system in a second mode of operation.

2. The method of claim 1, wherein a known position of the object is used to initialize a floating ambiguity value in the carrier-phase measurements.

3. The method of claim 2, wherein the known position of the object is the second position.

4. The method of claim 2, wherein the known position of the object is input by a user.

5. The method of claim 1, wherein the second mode of operation is used if communication with the local positioning system is available.

6. The method of claim 1, wherein the first mode of operation is used when communication with the local positioning system is lost and the second mode of operation is used when the communication with the local positioning system is available again.

7. The method of claim 1, wherein the second mode of operation is used if a distance from the local positioning system to the object is less than a pre-determined value.

8. The method of claim 1, wherein the first mode of operation is used if communication with the local positioning system is lost.

9. The method of claim 1, wherein the first and second modes of operation are used substantially simultaneously, and a difference between the second position and the first position is used to initialize a floating ambiguity value in the carrier phase measurements.

10. The method of claim 1, wherein the first and second modes of operation are used substantially simultaneously, and a difference between the second position and the first position is used to determine a third position of the object.

11. The method of claim 1, further comprising determining a third position of the object in accordance with information received from a local reference receiver using real-time kinematic positioning in a third mode of operation.

12. The method of claim 11, wherein the third mode of operation is used when communication with the local positioning system is lost and the second mode of operation is used when the communication with the local positioning system is available again.

13. The method of claim 11, wherein the first mode of operation is used when communication with the local reference receiver and the local positioning system is lost, the second mode of operation is used when communication with the local positioning system is available, and wherein the third mode of operation is used when the communication with the local reference receiver is available and the communication with the local positioning system is lost.

14. The method of claim 11, wherein the first mode of operation is used if a distance from the local positioning system to the object is greater than a first pre-determined value, the second mode of operation is used if the distance from the local positioning system to the object is less than a second pre-determined value, and the third mode of operation is used if the distance from the local positioning system to the object is between the first pre-determined value and the second pre-determined value.

15. A computer readable medium storing therein computer readable program instructions that, when executed by a processor, cause the processor to perform a method for positioning or navigating an object associated with both a local positioning system and a wide-area differential satellite positioning system, the program instructions comprising:

instructions for determining a first position of the object in accordance with carrier-phase measurements using the wide-area differential satellite positioning system in a first mode of operation; and

instructions for determining a second position of the object in accordance with information received from the local positioning system in a second mode of operation.

16. A satellite navigation receiver configured to operate in a first mode and a second mode of operation, wherein in the first mode of operation a first position of an object are determined in accordance with carrier-phase measurements using a wide-area differential satellite positioning system, and wherein in the second mode of operation a second position of the object is determined in accordance with information received from a local positioning system.

17. A satellite navigation receiver, comprising:

a memory;

a processor; and

a program, stored in the memory and executed by the processor, the program including;

instructions for determining a first position of the object in accordance with carrier-phase measurements using the wide-area differential satellite positioning system; and

instructions determining a second position of the object using the local positioning system.

18. A satellite navigation receiver, comprising an integrated circuit configured to perform:

operations for determining a first position of the object in accordance with carrier-phase measurements using the wide-area differential satellite positioning system; and

operations for determining a second position of the object using the local positioning system.

19. A satellite navigation receiver, comprising:

a memory means;

a processor means; and

a program means, stored in the memory means and executed by the processor means, for positioning or navigating an object, the program means including;

instructions for determining a first position of the object in accordance with carrier-phase measurements using the wide-area differential satellite positioning system; and

instructions determining a second position of the object using the local positioning system.