Systems and methods for solution separation for ground-augmented multi-constellation terminal area navigation and precision approach guidance

• US 8,976,064 B2
• Filed: 09/06/2012
• Issued: 03/10/2015
• Est. Priority Date: 09/06/2012
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Brenner, Mats Anders
• Primary Examiner(s): Issing, Gregory C
• Application Number:
  US13/605,405
• Publication Number:
  US 20140062765A1
• Time in Patent Office: 915 Days
• Field of Search: 342/357.58
• US Class Current: 342/357.58
• CPC Class Codes: G01S 19/072 Ionosphere corrections
• CPC Class Codes: G01S 19/15 Aircraft landing systems
• CPC Class Codes: G01S 19/20 Integrity monitoring, fault detection or fault isolation of space segment
• CPC Class Codes: G01S 19/28 Satellite selection
• CPC Class Codes: G01S 19/41 Differential correction, e.g. DGPS [differential GPS]
• CPC Class Codes: G01S 5/009 Transmission of differential positioning data to mobile

Abstract

A navigation system includes first receiver receiving satellite signals, second receiver receiving differential correction data from ground receivers, and processing device coupled to receivers. Processing device determines correction data for satellite signals based on differential correction; determines position solution based on satellite signals and corresponding differential correction data; determines first position sub-solutions based on satellite signals from all but one satellite (different for each first position sub-solution) and corresponding differential correction data; calculates first separations as function of first differences between position solution and first position sub-solutions; determines second position sub-solutions for mobile object based on satellite signals and corresponding differential correction data from all but one block of ground receivers (different for each second position sub-solution); calculates second separations as function of second differences between position solution and second position sub-solutions; detects error in position solution when one of first separations or second separations exceed corresponding separation limit.

Claims

1. A navigation system for a mobile object, comprising:

a first receiver configured for reception of satellite signals from a plurality of satellites;

a second receiver configured for reception of differential correction data from a plurality of blocks of ground receivers;

at least one processing device communicatively coupled to the first receiver and the second receiver;

wherein the at least one processing device is configured to determine correction data for each of the satellite signals from the plurality of satellites based on the differential correction data received through the second receiver from the plurality of blocks of ground receivers;

wherein the at least one processing device is configured to determine a position solution for the mobile object based on the satellite signals received from the plurality of satellites and corresponding differential correction data received through the second receiver from the plurality of blocks of ground receivers;

wherein the at least one processing device is configured to determine a plurality of first position sub-solutions for the mobile object based on satellite signals from all but one single satellite of the plurality of satellites, the one single satellite different for each of the plurality of first position sub-solutions, and corresponding differential correction data from the plurality of blocks of ground receivers;

wherein the at least one processing device is configured to calculate first separations as a function of first differences between the position solution and the first position sub-solutions, the first separations providing first indications of any faults degrading the accuracy of the position solution;

wherein the at least one processing device is configured to determine second position sub-solutions for the mobile object based on the satellite signals received from the plurality of satellites and corresponding differential correction data from all but one single block of ground receivers of the plurality of blocks of ground receivers, the single block of ground receivers different for each of the plurality of second position sub-solutions;

wherein the at least one processing device is configured to calculate second separations as a function of second differences between the position solution and the second position sub-solutions, the second separations providing second indications of any faults degrading the accuracy of the position solution; and

wherein the at least one processing device is configured to detect an error in the position solution when at least one of the first separations or the second separations exceed a corresponding separation limit.

2. The navigation system of claim 1, further comprising an inertial measurement unit communicatively coupled to the at least one processing unit;

wherein the inertial measurement unit is configured to measure inertial motion of the mobile object and supply inertial measurement data based on the measured inertial motion to the at least one processing unit; and

wherein the at least one processing unit is further configured to augment at least one of the position solution, the first position sub-solutions, and the second position sub-solutions based on the inertial measurement data received from the inertial measurement unit.

3. The navigation system of claim 1, wherein a first subset of the plurality of satellites belong to a first global navigation satellite system constellation;

wherein a second subset of the plurality of satellites belong to a second global navigation satellite system constellation; and

wherein the satellite signals received by the first receiver are from both the first subset and the second subset of the plurality of satellites.

4. The navigation system of claim 1, wherein at least one block of ground receivers of the plurality of blocks of ground receivers includes only one ground receiver.

5. The navigation system of claim 1, wherein at least one block of ground receivers of the plurality of block of ground receivers includes a plurality of ground receivers.

6. The navigation system of claim 1, wherein corresponding separation limits corresponding to at least two of the first separations and the second separations are different.

7. The navigation system of claim 1, wherein the mobile object is a vehicle.

8. The navigation system of claim 1, wherein the mobile object is an aircraft.

9. A method comprising:

determining correction data for each satellite signal received from a plurality of satellites, the correction data based on differential correction data received from a plurality of blocks of ground receivers;

determining a position solution for a mobile object using each of the satellite signals received from the plurality of satellites and corresponding differential correction data from the plurality of blocks of ground receivers;

determining a plurality of first position sub-solutions for the mobile object based on satellite signals from all but one single satellite of the plurality of satellites, the one single satellite different for each of the plurality of first position sub-solutions, and corresponding differential correction data from the plurality of blocks of ground receivers;

calculating first separations as functions of first differences between the position solution and each of the plurality of first position sub-solutions, the first separations providing first indications of any faults degrading the accuracy of the position solution;

determining a plurality of second position sub-solutions for the mobile object based on satellite signals from the plurality of satellites and corresponding differential correction data from all but one single block of ground receivers of the plurality of blocks of ground receivers, the single block of ground receivers different for each of the plurality of second position sub-solutions;

calculating second separations as functions of second differences between the position solution and each of the plurality of second position sub-solutions, the second separations providing second indications of any faults degrading the accuracy of the position solution; and

detecting an error in the position solution when at least one of the first separations or the second separations exceed a corresponding separation limit.

10. The method of claim 9, further comprising augmenting at least one of the position solution, the first position sub-solution, and the second position sub-solution based on the inertial measurement data received from an inertial measurement unit measuring inertial motion of the mobile object.

11. The method of claim 9, wherein a first subset of the plurality of satellites belong to a first global navigation satellite system constellation;

wherein a second subset of the plurality of satellites belong to a second global navigation satellite system constellation; and

wherein the satellite signals received from the plurality of satellites are from both the first subset and the second subset of the plurality of satellites.

12. The method of claim 9, wherein at least one block of ground receivers of the plurality of blocks of ground receivers includes only one ground receiver.

13. The method of claim 9, wherein corresponding separation limits corresponding to at least two of the first separations and the second separations are different.

14. The method of claim 9, wherein the mobile object is an aircraft.

15. A navigation system, comprising:

a first receiver configured for reception of a plurality of satellite signals;

a second receiver configured for reception of differential correction data for a plurality of blocks of stationary receivers that are also receiving the plurality of satellite signals;

at least one processing device communicatively coupled to the first receiver and the second receiver;

wherein the at least one processing device is configured to determine correction data for each of the plurality of satellite signals based on the differential correction data received through the second receiver from the plurality of blocks of stationary receivers;

wherein the at least one processing device is configured to determine a position solution for the vehicle using each of the plurality of satellite signals received through the first receiver and corresponding correction data received through the second receiver from the plurality of blocks of stationary receivers;

wherein the at least one processing device is configured to determine a first plurality of position sub-solutions for the navigation system using a first plurality of subsets of the plurality of satellite signals and corresponding correction data, wherein each of the first plurality of subsets of the plurality of satellite signals includes signals from all but one single satellite, the one single satellite different for each of the first plurality of subsets of the plurality of satellite signals;

wherein the at least one processing device is configured to calculate first separations as a function of first differences between the position solution and the first plurality of position sub-solutions, the first separations providing first indications of any faults degrading the accuracy of the position solution;

wherein the at least one processing device is configured to determine a second plurality of position sub-solutions for the navigation system using each of the plurality of satellite signals and corresponding correction data received from a second plurality of subsets of the plurality of blocks of stationary receivers, wherein each of the second plurality of subsets of the plurality of blocks of stationary receivers includes all but one block of stationary receivers, the one block of stationary receivers excluded being different for each of the second plurality of subsets of the plurality of blocks of stationary receivers;

wherein the at least one processing device is configured to calculate second separations as a function of second differences between the position solution and the second plurality of position sub-solutions, the second separations providing second indications of any faults degrading the accuracy of the position solution; and

wherein the at least one processing device is configured to detect an error in the position solution when at least one of the first separations or the second separations exceed a corresponding separation limit.

16. The navigation system of claim 15, further comprising an inertial measurement unit communicatively coupled to the at least one processing unit;

wherein the inertial measurement unit is configured to measure inertial motion of the mobile object and supply inertial measurement data based on the measured inertial motion to the at least one processing unit; and

wherein the at least one processing unit is further configured to augment at least one of the position solution, the first position sub-solutions, and the second position sub-solutions based on the inertial measurement data received from the inertial measurement unit.

17. The navigation system of claim 15, wherein a first subset of the plurality of satellites belong to a first global navigation satellite system constellation;

wherein a second subset of the plurality of satellites belong to a second global navigation satellite system constellation; and

wherein the satellite signals received by the first receiver are from both the first subset and the second subset of the plurality of satellites.

18. The navigation system of claim 15, wherein at least one block of ground receivers of the plurality of blocks of ground receivers includes only one ground receiver.

19. The navigation system of claim 15, wherein corresponding separation limits corresponding to at least two of the first separations and the second separations are different.

20. The navigation system of claim 15, wherein the mobile object is an aircraft.