Triply redundant integrated navigation and asset visibility system

• US 8,355,866 B2
• Filed: 10/13/2011
• Issued: 01/15/2013
• Est. Priority Date: 10/17/2006
• Status: Active Grant

• Current Assignee: UT-Battelle LLC
• Original Assignee: UT-Battelle LLC
• Inventors: Smith, Stephen F., Moore, James A.
• Primary Examiner(s): To, Tuan C.
• Application Number:
  US13/272,973
• Publication Number:
  US 20120029818A1
• Time in Patent Office: 460 Days
• Field of Search: 701/468, 342/450, 342/350, 342/464, 342/453, 342/386, 342/357.31, 375/150, 375/147, 375/295, 375/316
• US Class Current: 701/468
• CPC Class Codes: G01C 21/1654 with electromagnetic compass
• CPC Class Codes: G01S 1/24 the synchronised signals being pulses or equivalent modulations on carrier waves and the transit times being compared by measuring the difference in arrival time of a significant part of the modulations , e.g. LORAN systems
• CPC Class Codes: G01S 19/46 the supplementary measurement being of a radio-wave signal type
• CPC Class Codes: G01S 19/47 the supplementary measurement being an inertial measurement, e.g. tightly coupled inertial

Abstract

Methods and apparatus are described for a navigation system. A method includes providing a global positioning system fix having a plurality of tracking parameters; providing a theater positioning system fix; monitoring the plurality of tracking parameters for predetermined conditions; and, when the predetermined conditions are met, sending a notifying signal and switching to the theater positioning system fix as a primary fix. An apparatus includes a system controller; a global positioning system receiver coupled to the system controller; a radio frequency locating receiver coupled to the system controller; and an operator interface coupled to the system controller.

Claims

1. A method comprising:

providing a Global Positioning System fix having a plurality of tracking parameters by a Global Positioning System receiver;

providing a Theater Positioning System fix by a Theater Positioning System receiver;

monitoring the plurality of tracking parameters for predetermined conditions;

and, when the predetermined conditions are met, sending a notifying signal and switching to the Theater Positioning System fix as a primary fix.

2. The method of claim 1, further comprising:

adjusting the Theater Positioning System fix based on the Global Positioning System fix.

3. The method of claim 1, wherein the plurality of tracking parameters are selected from the group comprising data integrity, tracking loop error magnitudes and variances, loop lock states, continuity of position fixes, internal RF/IF AGC values, and front-end overload indicators.

4. The method of claim 1, further comprising:

monitoring the plurality of tracking parameters for a second set of predetermined conditions;

and, when the second set of predetermined conditions are met, sending a second notifying signal and switching to the Global Positioning System fix as a primary fix.

5. The method of claim 1, further comprising:

monitoring the Global Positioning System fix and the Theater Positioning System fix;

and, if the difference between the Global Positioning System fix and the Theater Positioning System fix exceeds a predetermined threshold value, sending a second notifying signal and switching to the Theater Positioning System as a primary fix.

6. The method of claim 1, further comprising:

providing an Inertial Navigation System fix;

calibrating the Inertial Navigation System fix based on the Global Positioning System fix.

7. The method of claim 6, further comprising:

providing a precision timing signal;

using the precision timing signal to coordinate the providing of the Global Positioning System fix, the providing of the Theater Positioning System fix, and the providing of the inertial Navigation System fix.

8. The method of claim 6, further comprising:

integration processing of the providing of the Global Positioning System fix, the providing of the Theater Positioning System fix, and the providing of the Inertial Navigation System fix.

9. The method of claim 8, wherein the integration processing is selected from the group comprising triple-input Kalman filtering, Allan filtering, multidimensional kernel techniques, or combinations thereof.

10. The method of claim 6, further comprising:

providing a plurality of local position sensors;

initially calibrating the Inertial Navigation System fix using the plurality of local position sensors.

11. The method of claim 6, wherein the Theater Positioning System fix has a second plurality of tracking parameters, and further comprising:

monitoring the second plurality of tracking parameters for a second set of predetermined conditions;

and, when the second set of predetermined conditions are met, sending a second notifying signal and switching to the Inertial Navigation System fix as a primary fix.

12. The method of claim 1, further comprising:

providing a plurality of environmental constants;

adjusting the Theater Positioning fix based on the plurality of environmental constants.

13. The method of claim 1, further comprising:

performing a signal integrity test on Global Positioning System data associated with a Global Positioning System satellite in communication with the Global Positioning System receiver; and

excluding the Global Positioning System data from the Global Positioning System fix based on results of the signal integrity test.

14. The method of claim 1, further comprising:

performing a test of Global Positioning System data associated with a Global Positioning System satellite in communication with the Global Positioning System receiver for sufficiency, consistency, stability, and overall validity; and

excluding pseudorange and time data associated with the Global Positioning System satellite from the Global Positioning System fix based on results of the test.

15. The method of claim 1, further comprising:

performing a signal integrity test on Theater Positioning System data associated with a Theater Positioning System transmitter in communication with the Theater Positioning System receiver; and

excluding the Theater Positioning System data from the Theater Positioning System fix based on results of the signal integrity test.

16. A method comprising:

acquiring Global Positioning System data by a Global Positioning System receiver;

acquiring Theater Positioning System location data by a Theater Positioning System locating receiver;

acquiring Inertial Navigation System data by Inertial Navigation System electronics;

providing a precision timing signal;

performing a first signal integrity test on the Global Positioning System data;

outputting a Global Positioning System fix associated with the Global Positioning System receiver as a primary position fix in response to a determination that the Global Positioning System data passed the first signal integrity test;

performing a second signal integrity test on the Theater Positioning System location data in response to a determination that the Global Positioning System data failed the first signal integrity test;

outputting a Theater Positioning System fix associated with the Theater Positioning System receiver as the primary position fix in response to a determination that the Theater Positioning System data passed the second signal integrity test;

performing a third signal integrity test, in response to a determination that the Theater Positioning System data failed the second signal integrity test, to determine whether the Global Positioning System data and the Theater Positioning System data are combinable to form a complete hybrid GPS/TPS position fix;

combining the Global Positioning System data and the Theater Positioning System data to output the hybrid GPS/TPS position fix as the primary position fix in response to a determination that the Global Positioning System data and the Theater Positioning System data passed the third signal integrity test;

performing a fourth signal integrity test on the Inertial Navigation System data in response to a determination that the Global Positioning System data and the Theater Positioning System data failed the third signal integrity test; and

outputting an Inertial Navigation System fix as the primary position fix in response to a determination that the Inertial Navigation System data passed the fourth signal integrity test.

17. An apparatus comprising:

a system controller;

a timing subsystem coupled to the system controller;

a Global Positioning System receiver coupled to the system controller;

a Theater Positioning System receiver coupled to the system controller; and

inertial Navigation System electronics coupled to the system controller;

where the system controller is configured to;

perform a first signal integrity test on Global Positioning System data received from the Global Positioning System receiver;

output a Global Positioning System fix associated with the Global Positioning System receiver as a primary position fix in response to a determination that the Global Positioning System data passed the first signal integrity test;

perform a second signal integrity test on Theater Positioning System location data, received from the Theater Positioning System receiver, in response to a determination that the Global Positioning System data failed the first signal integrity test;

output a Theater Positioning System fix associated with the Theater Positioning System receiver as the primary position fix in response to a determination that the Theater Positioning System data passed the second signal integrity test;

perform a third signal integrity test, in response to a determination that the Theater Positioning System data failed the second signal integrity test, to determine whether the Global Positioning System data and the Theater Positioning System data are combinable to form a complete hybrid GPS/TPS position fix;

combine the Global Positioning System data and the Theater Positioning System data to output the hybrid GPS/TPS position fix as the primary position fix in response to a determination that the Global Positioning System data and the Theater Positioning System data passed the third signal integrity test;

perform a fourth signal integrity test on Inertial Navigation System data received from the Inertial Navigation System electronics in response to a determination that the Global Positioning System data and the Theater Positioning System data failed the third signal integrity test; and

output an Inertial Navigation System fix as the primary position fix in response to a determination that the Inertial Navigation System data passed the fourth signal integrity test.