Synchronizing a radio network with end user radio terminals

• US 20060013347A1
• Filed: 08/16/2005
• Published: 01/19/2006
• Est. Priority Date: 05/21/2001
• Status: Active Grant

• Current Assignee: CSR Technology Incorporated (Qualcomm, Inc.)
• Original Assignee: CSR Technology Incorporated (Qualcomm, Inc.)
• Inventors: Zhang, Gengsheng, Brown, Jim, Garin, Lionel
• Granted Patent: US 7,925,210 B2
• Time in Patent Office: Days
• US Class Current: 375/354
• CPC Class Codes: H04B 7/2693 Centralised synchronisation, i.e. using external universal time reference, e.g. by using a global positioning system [GPS] or by distributing time reference over the wireline network

Abstract

Synchronizing a Radio Network with End User Radio Terminals A Mobile Station that is able to receive GPS signals and compare the frequency of the GPS received time signal with a time signal from a network in order to determine the difference between the signals and communicate that difference back to the network.

Claims

1. A wireless communication device, comprising:

a communication receiver in the wireless communication device;

an absolute time signal received at the wireless communication device;

a network time signal received at the communication receiver of the communication device; and

a memory that stores an offset of the absolute time signal from the network time signal.

2. The wireless communication device of claim 1, where the absolute time signal is a Global Positioning System (GPS) clock signal.

3. The wireless communication device of claim 1, comprising:

a GPS receiver in receipt of the absolute time signal that is a Global Positioning System clock signal; and

a controller in signal communication with the GPS receiver, the communication receiver and the memory, where the controller determines the offset.

4. The wireless communication device of claim 3, comprising:

a frequency error of a clock associated with the network time signal is calculated by the controller.

5. The wireless communication device of claim 3, further comprising:

a drift rate determination made by the controller based on a plurality of offset measurements.

6. The wireless communication device of claim 3, comprising:

a transmitter associated with the wireless communication device that transmits the offset for receipt by another wireless communication device.

7. The wireless communication device of claim 6, where the offset is transmitted over another communication network other than a communication network that provides service to the communication receiver.

8. The wireless communication device of claim 3, where a transmitter transmits the offset for receipt by a base station.

9. The wireless communication device of claim 3, comprising:

a hardware pulse that the controller tags with an internal clock, where the hardware pulse has a known relationship with the Global Positioning System clock signal.

10. The wireless communication device of claim 9, comprising:

a frame and a bit number associated with the hardware pulse being sent to the GPS receiver.

11. The wireless communication device of claim 10, wherein the frame is a GSM frame.

12. A method for wireless communication, comprising:

receiving a network time signal over a first communication network at a communication receiver in the wireless communication device;

receiving a absolute time signal at the wireless communication device; and

storing in a memory an offset of the absolute time signal from the network time signal.

13. The method for wireless communication of claim 12, where the absolute time signal is a Global Positioning System (GPS) clock signal.

14. The method for wireless communication of claim 12, comprising:

receiving at a GPS receiver the absolute time signal that is a Global Positioning System clock signal; and

determining the offset at a controller that is in signal communication with the GPS receiver, the communication receiver and the memory.

15. The method for wireless communication of claim 14, comprising:

calculating a frequency error of a clock associated with the network time signal.

16. The method for wireless communication of claim 14, further comprising:

determining a drift rate by the controller based upon multiple offset measurements.

17. The method for wireless communication of claim 14, comprising:

transmitting at a transmitter associated with the wireless communication device the offset for receipt by another wireless communication device.

18. The method for wireless communication of claim 17, where the offset is transmitted over a second communication network.

19. The method wireless communication of claim 14, comprising:

transmitting with a transmitter, the offset for receipt by a base station.

20. The method of wireless communication of claim 14, comprising:

generating a hardware pulse that the controller tags with an internal clock, where the hardware pulse has a known relationship with Global Positioning System clock signal.

21. The method of wireless communication of claim 20, comprising:

sending a frame and a bit number associated with the hardware pulse to the GPS receiver.

22. A signal-bearing medium with machine-readable instructions for wireless communication, comprising:

machine-readable instructions for receiving a network time signal at a communication receiver in the wireless communication device;

machine-readable instructions for receiving an absolute time signal at the wireless communication device; and

machine-readable instructions for storing in a memory an offset of the absolute time signal from the network time signal.

23. The signal-bearing medium for wireless communication of claim 22, where the absolute time signal is a Global Positioning System (GPS) clock signal.

24. The signal-bearing medium for wireless communication of claim 22, where the network time signal is a cellular telephone time signal.

25. The signal-bearing medium for wireless communication of claim 22, comprising:

machine-readable instructions for receiving at a GPS receiver the absolute time signal that is a Global Positioning System clock signal; and

machine-readable instructions for determining the offset at a controller that is in signal communication with the GPS receiver, the communication receiver and the memory.

26. The signal-bearing medium for wireless communication of claim 25, comprising:

machine-readable instructions for calculating a frequency error of a clock associated with the network time signal.

27. The signal-bearing medium for wireless communication device of claim 25, further comprising:

machine-readable instructions for determining a drift rate by the controller based upon multiple offset measurements.

28. The signal-bearing medium for wireless communication of claim 25, comprising:

machine-readable instructions for transmitting at a transmitter associated with the wireless communication device the offset for receipt by another wireless communication device.

29. The signal-bearing medium for wireless communication of claim 28, where the offset is transmitted over another communication network other than a communication network.

30. The signal-bearing medium for wireless communication of claim 25, comprising:

machine-readable instructions for transmitting with a transmitter, the offset for receipt by a base station.

31. The signal bearing medium for wireless communication of claim 25, comprising:

machine-readable instructions for generating a hardware pulse that the controller tags an internal clock, where the hardware pulse has a known relationship with the Global Positioning System Clock Signal.

32. The signal-bearing medium for wireless communication of claim 31, comprising:

machine-readable instructions for sending a frame and a bit number associated with the hardware pulse to the GPS receiver.

33. A wireless device, comprising:

a receiver in the wireless device in receipt of a message that identifies absolute time with a current frame/bit number;

a call processing section coupled to the receiver that generates a time mark aligned with the current frame/bit number; and

a GPS receiver in the wireless device in receipt of a signal from the call processing section that identifies the frame/bit number associated with the time mark that enables the GPS receiver to compensate for network delay while determining a GPS posistion.

34. The wireless device of claim 33, where the frame and bit number is a GSM frame/bit number.

35. The wireless device of claim 33, where the network delay further includes compensation for time estimation errors.

36. A method for synchronizing a wireless device, comprising:

receiving at a receiver in the wireless device a message that identifies absolute time with a current frame/bit number;

generating in a call processing section that is coupled to the receiver, a time mark aligned with the current frame/bit number;

receiving at a GPS receiver in the wireless device a signal from the call processing section that identifies the frame/bit number associated with the time mark; and

compensating for network delay in the GPS receiver using the frame/bit number.

37. The method of claim 36, where the frame/bit number is a GSM frame and bit number.

38. The method of claim 36, where compensating for network delay further includes compensating for time estimation errors.