GPS-assisted mobile phone clock for use in non-digital service coverage areas

• US 20050135194A1
• Filed: 12/17/2003
• Published: 06/23/2005
• Est. Priority Date: 12/17/2003
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Laboratories of America Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Ishii, Atsushi
• Granted Patent: US 7,518,958 B2
• Time in Patent Office: Days
• US Class Current: 368/47
• CPC Class Codes: G04R 20/02 the radio signal being sent by a satellite, e.g. GPS

Abstract

A method of setting an internal clock in a GPS-equipped mobile communication device when the mobile communication device is not in a digital service area includes determining whether digital service is available, including determining whether digital service is available by determining the elapsed time from the last receipt of a digital service contact, and, if digital service is not available, detecting a GPS time signal from a single GPS satellite.

Claims

1. A method of setting an internal clock in a GPS-equipped mobile communication device when the mobile communication device is not in a digital service area, comprising:

powering-up the mobile communication device; and

determining whether digital service is available, and, if digital service is not available, detecting a GPS time signal from any GPS satellite.

2. The method of claim 1 wherein said determining includes determining whether digital service is available by determining the elapsed time from the last receipt of a digital service contact.

3. The method of claim 1 wherein said determining includes determining whether digital service is available by scanning for all possible digital channels.

4. The method of claim 1 wherein said detecting includes detecting after a pre-determined period of time, a GPS time signal to update the internal clock in the mobile communication device.

5. The method of claim 1 wherein said detecting includes detecting a difference between the GPS time signal and the internal clock time, and, if the difference exceeds a pre-determined value, updating the internal clock time as a function of the GPS time signal.

6. The method of claim 1 wherein a user interface is provided to allow the user to regulate the GPS time adjustment.

7. The method of claim 1 which further includes detecting location from plural GPS satellites and determining local time as a function of the GPS time signal and location.

8. A method of setting an internal clock in a GPS-equipped mobile communication device when the mobile communication device is not in a digital service area, comprising:

determining whether digital service is available, including determining whether digital service is available by determining the elapsed time from the last receipt of a digital service contact, and, if digital service is not available,

detecting a GPS time signal from a single GPS satellite.

9. The method of claim 8 wherein said determining includes determining whether digital service is available by scanning for all possible digital channels.

10. The method of claim 8 wherein said detecting includes detecting after a pre-determined period of time, a GPS time signal to update the internal clock in the mobile communication device.

11. The method of claim 8 wherein said detecting includes detecting a difference between the GPS time signal and the internal clock time, and, if the difference exceeds a pre-determined value, updating the internal clock time as a function of the GPS time signal.

12. The method of claim 8 wherein a user interface is provided to allow the user to regulate the GPS time adjustment.

13. The method of claim 8 which further includes detecting location from plural GPS satellites and determining local time as a function of the GPS time signal and location.