In-vehicle clock synchronization with local time

• US 20040203951A1
• Filed: 12/05/2002
• Published: 10/14/2004
• Est. Priority Date: 12/05/2002
• Status: Active Grant

• Current Assignee: General Motors LLC (General Motors Company)
• Original Assignee: General Motors Corporation (General Motors Company)
• Inventors: Mazzara, William E. Jr., Lenane, Timothy D.
• Granted Patent: US 7,190,946 B2
• Time in Patent Office: Days
• US Class Current: 455/466
• CPC Class Codes: G06F 1/14 Time supervision arrangements, e.g. real time clock
• CPC Class Codes: H04W 4/02 Services making use of location information

Abstract

The present invention is a system and method for providing local time to a mobile vehicle. A time information message is received at an in-vehicle telematics unit, which monitors for a time-update trigger event. A time-update message is sent from the telematics unit to a vehicle bus in response to the time-update trigger event. A computer usable medium with suitable computer program code is employed to provide local time to a mobile vehicle.

Claims

1. A method for providing local time to a mobile vehicle, comprising:

receiving a time information message at an in-vehicle telematics unit;

monitoring for a time-update trigger event; and

sending a time-update message from the telematics unit to a vehicle bus in response to the time-update trigger event.

2. The method of claim 1 wherein the time information message comprises a synchronization channel message including a system time and a local time offset.

3. The method of claim 1 wherein the time information message is broadcast on a control channel of a wireless service provider.

4. The method of claim 1 wherein the time information message is broadcast from a terrestrial radio antenna.

5. The method of claim 1 wherein the time-update trigger event is selected from the group consisting of a periodic trigger event, a predetermined time setting, a time-zone crossing event, a mobile vehicle ignition event, a time-update request, a power restoration event, and an unsynchronized clock determination.

6. The method of claim 1 wherein the time-update message includes the local time.

7. The method of claim 1 wherein the time-update message includes a local time zone indicator.

8. The method of claim 1 wherein the time-update message includes a date indicator.

9. The method of claim 1 further comprising:

receiving the time-update message at at least one time-receiving unit operably coupled to the vehicle bus; and

updating an internal time of the at least one time-receiving unit based on the time-update message.

10. The method of claim 9 wherein the at least one time-receiving unit is selected from the group consisting of an in-vehicle clock, a vehicle clock-radio, an infotainment system, an in-vehicle entertainment unit, and a vehicle electronic module.

11. The method of claim 1 further comprising:

displaying the local time on a time-receiving unit operably coupled to the vehicle bus.

12. The method of claim 11 further comprising:

displaying a local time zone indicator on the time-receiving unit.

13. A computer usable medium including a program to provide local time to a mobile vehicle, comprising:

computer program code to receive a time information message at an in-vehicle telematics unit;

computer program code to monitor for a time-update trigger event; and

computer program code to send a time-update message from the telematics unit to a vehicle bus in response to the time-update trigger event.

14. The computer usable medium of claim 13 further comprising:

computer program code to receive the time-update message at at least one time-receiving unit operably coupled to the vehicle bus; and

computer program code to update an internal time of the at least one time-receiving unit based on the time-update message.

15. The computer usable medium of claim 13 further comprising:

computer program code to display the local time on a time-receiving unit operably coupled to the vehicle bus.

16. The computer usable medium of claim 15 further comprising:

computer program code to display a local time zone indicator on the time-receiving unit.

17. A system to provide local time to a mobile vehicle, comprising:

means for receiving a time information message at an in-vehicle telematics unit;

means for monitoring for a time-update trigger event; and

means for sending a time-update message from the telematics unit to a vehicle bus in response to the time-update trigger event.

18. The system of claim 17 further comprising:

means for receiving the time-update message at at least one time-receiving unit operably coupled to the vehicle bus; and

means for updating an internal time of the at least one time-receiving unit based on the time-update message.

19. The system of claim 17 further comprising:

means for displaying the local time on a time-receiving unit operably coupled to the vehicle bus.

20. The system of claim 19 further comprising:

means for displaying a local time zone indicator on the time-receiving unit.