METHOD AND APPARATUS FOR A GLOBAL NAVIGATION SATELLITE SYSTEM RECEIVER COUPLED TO A HOST COMPUTER SYSTEM

• US 20100073228A1
• Filed: 03/11/2009
• Published: 03/25/2010
• Est. Priority Date: 09/22/2008
• Status: Active Grant

• Current Assignee: Sierra Wireless Incorporated
• Original Assignee: Sierra Wireless Incorporated
• Inventors: Smith, Vincent Maddock
• Granted Patent: US 7,986,263 B2
• Time in Patent Office: Days
• US Class Current: 342/357.270
• CPC Class Codes: G01S 19/235 Calibration of receiver components
• CPC Class Codes: G01S 19/256 relating to timing, e.g. time of week, code phase, timing offset
• CPC Class Codes: G01S 19/34 Power consumption

Abstract

The present invention provides a global navigation satellite system (GNSS) receiver apparatus, such as a GPS receiver, operable with a host computer system equipped with a real time clock configured to provide a time signal to the GNSS receiver apparatus. The time signal is used to facilitate acquisition of navigation and global timing information through observation of satellite signals. The global timing information is used to adjust the time signal and/or the real time clock to improve subsequent acquisitions of navigation and global timing information.

Claims

1. A global navigation satellite system receiver apparatus configured for operative coupling to a host computer system, the global navigation satellite system receiver apparatus comprising:

a) a navigation interface module configured to receive a host time signal from the host computer system during a navigation operation, the navigation interface module further configured to provide a navigation time signal based on at least the host time signal during said navigation operation; and

b) a satellite signal receiver module configured to use the navigation time signal to facilitate determination of a global time signal through reception of satellite signals during said navigation operation;

wherein the global time signal is provided to the navigation interface module during an update operation, the navigation interface module configured to use at least the global time signal to configure one or more adjustments during said update operation, said one or more adjustments configured to facilitate future navigation operations.

2. The apparatus of claim 1, wherein the host time signal is provided by a host real time clock of the host computer system.

3. The apparatus of claim 2, wherein the one or more adjustments during the update operation include an adjustment of the host real time clock.

4. The apparatus of claim 2, further comprising a clock gateway module of the host real time clock, the clock gateway module configured to manage one or more adjustments to the host real time clock, the one or more adjustments provided by one or more sources.

5. The apparatus of claim 4, wherein the clock gateway module is further configured to provide one or more application specific host time signals, wherein each application specific host time signal is independent.

6. The apparatus of claim 1, wherein the navigation interface module further comprises a time signal adjustment module, the time signal adjustment module configured to derive the navigation time signal from the host time signal based on a parameterized time derivation procedure.

7. The apparatus of claim 6, wherein the one or more adjustments configured during the update operation include an adjustment to the one or more parameters of the parameterized time derivation procedure.

8. The apparatus of claim 1, the apparatus further comprising a host computer module of the host computer system, the host computer module configured to facilitate the one or more adjustments during the update operation.

9. The apparatus of claim 1, wherein the one or more adjustments during the update operation are configured to facilitate synchronicity between the navigation time signal and the global time signal.

10. The apparatus of claim 1, wherein the navigation time signal is generated at least in part based on information about the host real time clock, said information selected from the group comprising:

clock accuracy, clock drift, clock skew, power events, temperature variation, component variation, and clock adjustment events.

11. A method of operating a global navigation satellite system receiver apparatus operatively coupled to a host computer system, the method comprising:

a) performing a navigation operation, the navigation operation comprising;

i) providing a navigation time signal based on at least a host time signal from the host computer;

ii) using the navigation time signal to perform a satellite signal reception operation; and

iii) determining a global time signal at least in part based on information obtained from the satellite signal reception operation; and

b) using at least the global time signal to perform one or more adjustments to facilitate future navigation operations.

12. The method of claim 11, wherein the host time signal is provided by a host real time clock of the host computer system.

13. The method of claim 12, wherein the one or more adjustments include an adjustment of the host real time clock.

14. The method of claim 12, wherein the host real time clock services one or more auxiliary applications and wherein the method further comprising the step of:

providing an application specific host time signal for each of the one or more auxiliary applications, wherein each application specific host time signal is independent of the host time signal.

15. The method of claim 11, wherein the navigation time signal is derived from the host time signal based on a parameterized time derivation procedure.

16. The method of claim 15, wherein the one or more adjustments performed to facilitate future navigation operations include an adjustment to the one or more parameters of the parameterized time derivation procedure.

17. The method of claim 11, wherein the one or more adjustments performed to facilitate future navigation operations facilitate synchronicity between the navigation time signal and the global time signal.

18. The method of claim 11, wherein providing the navigation time signal further comprises modifying the host time signal according to a modification schema, wherein the one or more adjustments include an adjustment to the modification schema.

19. The method of claim 18, wherein the modification schema is based at least in part on information selected from the group comprising:

clock accuracy, clock drift, clock skew, power events, temperature variation, component variation, and clock adjustment events.

20. A global navigation satellite system (GNSS) enabled system comprising:

a) a host computer module operatively coupled to a host real time clock, the host real time clock configured to provide a host time signal; and

b) a global navigation satellite system receiver apparatus operatively coupled to the host computer module, the global navigation satellite system receiver apparatus comprising;

i) a navigation interface module configured to receive the host time signal during a navigation operation, the navigation interface module further configured to provide a navigation time signal based on at least the host time signal during said navigation operation; and

ii) a satellite signal receiver module configured to use the navigation time signal to facilitate determination of a global time signal through reception of satellite signals during said navigation operation;

wherein the global time signal is provided to the navigation interface module during an update operation, the navigation interface configured to use at least the global time signal to configure one or more adjustments during said update operation, said one or more adjustments configured to facilitate future navigation operations.