Method of synchronizing a wireless device using an external clock

• US 20070064742A1
• Filed: 09/20/2005
• Published: 03/22/2007
• Est. Priority Date: 09/20/2005
• Status: Active Grant

• Current Assignee: North Star Innovations Inc. (Wi-LAN Inc.)
• Original Assignee: Freescale Semiconductor, Inc. (NXP Semiconductors NV)
• Inventors: Shvodian, William
• Granted Patent: US 7,573,865 B2
• Time in Patent Office: Days
• US Class Current: 370/503
• 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

A method is provided for operating a dual-use wireless device. The method includes: receiving an external timing signal (460) at a first wireless circuit (480) in the device (605); synchronizing a first clock in the first wireless circuit with the external timing signal (610); sending a first internal timing signal (570) from the first wireless circuit to a second wireless circuit in the device, after the synchronizing (615); and listening for a remote periodic control signal at the second wireless circuit for a set monitoring time, a start of the monitoring time being based on the first internal timing signal (865). The second wireless circuit sends an association request if the second wireless circuit hears the remote periodic control signal within the monitoring time (875), and sends a local periodic control signal if the second wireless circuit does not hear the remote periodic control signal within the monitoring time (625).

Claims

1. A method of transmitting a periodic control signal in a dual-use wireless device, comprising:

receiving an external timing signal at a first wireless circuit in the dual-use wireless device;

synchronizing a first clock in the first wireless circuit with the external timing signal;

sending a first internal timing signal from the first wireless circuit to a second wireless circuit in the dual-use wireless device, after synchronizing the first clock with the external timing signal; and

broadcasting the periodic control signal at the second wireless circuit based on the first internal timing signal.

2. A method of transmitting a periodic control signal, as recited in claim 1, further comprising waiting a delay time between sending the first internal timing signal and broadcasting the periodic control signal.

3. A method of transmitting a periodic control frame, as recited in claim 2, wherein the delay time is one of:

randomly determined, or iteratively chosen from a predetermined set of possible delay times.

4. A method of transmitting a periodic control signal, as recited in claim 1, further comprising:

synchronizing a second clock in the second wireless circuit with the first internal timing signal; and

generating a second internal timing signal in the second wireless circuit, after synchronizing the second clock with the first internal timing signal,

wherein the periodic control signal is broadcast in response to the second internal timing signal.

5. A method of transmitting a periodic control signal, as recited in claim 4, further comprising waiting a delay time between sending the second internal timing signal and broadcasting the periodic control signal.

6. A method of transmitting a periodic control frame, as recited in claim 5, wherein the delay time is one of:

randomly determined, or iteratively chosen from a predetermined set of possible delay times.

7. A method of transmitting a periodic control signal, as recited in claim 1, wherein the external timing signal is one of a global positioning system signal, a cell phone timing signal, a television clock signal, and a broadcast clock signal.

8. A method of transmitting a periodic control signal, as recited in claim 1, further comprising:

listening for an association request at the second wireless circuit for an association wait time after broadcasting the periodic control signal;

performing an association function if the association request is received within the association wait time; and

entering into a sleep mode if the association request is not received within a the association wait time.

9. A method of transmitting a periodic control signal, as recited in claim 1, wherein the second wireless circuit is an ultrawide bandwidth circuit.

10. A method of transmitting a periodic control signal, as recited in claim 1, wherein the method is implemented in an integrated circuit.

11. A method of operating a dual-use wireless device, comprising:

receiving an external timing signal at a first wireless circuit in the dual-use wireless device;

synchronizing a first clock in the first wireless circuit with the external timing signal;

sending a first internal timing signal from the first wireless circuit to a second wireless circuit in the dual-use wireless device, after synchronizing the first clock with the external timing signal; and

listening for a remote periodic control signal at the second wireless circuit in the dual-use device for a set monitoring time, a start time of the set monitoring time being based on the first internal timing signal.

12. A method of operating a dual-use wireless device, as recited in claim 11, wherein the timing signal is one of a global positioning system signal, a cell phone timing signal, a television clock signal, and a broadcast clock signal.

13. A method of operating a dual-use wireless device, as recited in claim 11, further comprising:

sending an association request from the second wireless circuit if the second wireless circuit hears the remote periodic control signal within the monitoring time;

sending a local periodic control signal from the second wireless circuit if the second wireless circuit does not hear the remote periodic control signal within the monitoring time.

14. A method of operating a dual-use wireless device, as recited in claim 13, further comprising:

listening at the second wireless circuit for an association request for an association wait time after sending the local periodic control signal;

performing an association function if the association request is received within the association wait time; and

entering into a sleep mode if the association request is not received within a the association wait time.

15. A method of operating a dual-use wireless device, as recited in claim 11, wherein the second wireless circuit is an ultrawide bandwidth circuit.

16. A method of operating a dual-use wireless device, as recited in claim 11, wherein the method is implemented in an integrated circuit.

17. A dual-use wireless communication device, comprising:

a first wireless circuit for receiving first wireless signals, including an external timing signal;

a second wireless circuit for receiving second wireless signals; and

a coordination circuit connected between the first wireless circuit and the second wireless circuit for providing an internal timing signal to the second wireless circuit, the internal timing signal being generated in response to the external timing signal.

18. A wireless communication device, as recited in claim 17, wherein the first wireless circuit is one of a cellular telephone circuit, a global positioning system receiver, a television receiver, and a broadcast clock receiver.

19. A wireless communication device, as recited in claim 17, wherein the second wireless circuit is an ultrawide bandwidth circuit.

20. A wireless communication device, as recited in claim 17, wherein the second wireless circuit is implemented on an integrated circuit.