Method and apparatus for minimizing time of reception during paging

• US 20030214937A1
• Filed: 05/17/2002
• Published: 11/20/2003
• Est. Priority Date: 05/17/2002
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Lindoff, Bengt, Eriksson, Hakan
• Granted Patent: US 7,463,599 B2
• Time in Patent Office: Days
• US Class Current: 370/350
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0245 according to signal strength
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 68/00 User notification, e.g. alerting and paging, for incoming communication, change of service or the like
• CPC Class Codes: H04W 68/025 Indirect paging
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method and apparatus for detecting a periodic message in a mobile communication system includes initiating, at a receiver, a reception of synchronization data a predetermined amount of time prior to a current periodic message. The predetermined amount of time is based on at least one of an estimated signal quality value from at least one prior periodic message and an estimated error in the at least one prior periodic message. The synchronization data is used to achieve synchronization, and the current periodic message is detected based on the synchronization.

Claims

1. A method for reducing time of reception during paging in a communication system, comprising the steps of:

receiving at least one paging-related message prior to receiving a current paging-related message;

determining an estimated signal quality value based on said at least one paging-related message;

determining a time period for receiving synchronization data based on said estimated signal quality value;

activating said receiver during said time period to receive a signal containing said synchronization data; and

synchronizing said receiver with the received signal based on said synchronization data.

2. The method of claim 1, wherein said at least one paging-related message includes a paging indicator message transmitted on a paging indicator channel.

3. The method of claim 1, wherein said at least one paging message includes a paging data message transmitted on a paging data channel.

4. The method of claim 1, wherein said estimated signal quality value comprises an estimate of a signal-to-noise ratio (SNR).

5. The method of claim 1, wherein said estimated signal quality value corresponds to a radio path profile estimate.

6. The method of claim 1, wherein said signal received during said time period further includes said current paging-related message.

7. The method of claim 6, wherein said time period starts at a start time prior to said paging-related message.

8. The method of claim 7, wherein the step of determining said time period includes identifying said start time based on said estimated signal quality value.

9. The method according to claim 8, wherein said time period ends at an end time subsequent to said paging-related message, the step of determining said time period including identifying said end time based on said estimated signal quality value.

10. The method of claim 9, wherein said paging-related message comprises a paging indicator message.

11. The method of claim 1, further comprising the steps of:

updating said estimated signal quality value based on said current paging-related message; and

determining an updated time period for receiving synchronization data based on said updated estimated signal quality value.

12. An apparatus for reducing time of reception during paging in a communication system, the apparatus comprising:

a receiver for receiving a plurality of paging-related messages;

a device for determining an estimated signal quality value from at least one of said plurality of paging messages received prior to receiving a current paging message; and

a controller for determining a time period for receiving synchronization data based on said estimated signal quality value and for activating said receiver during said time period to receive said synchronization data.

13. The apparatus of claim 12, further comprising a path searcher for detecting said synchronization data.

14. The apparatus of claim 12, wherein said estimated signal quality value comprises an estimate of a signal-to-noise ratio (SNR).

15. The apparatus of claim 12, wherein said estimated signal quality value corresponds to a radio path profile estimate.

16. The apparatus of claim 13, further comprising a rake receiver for de-spreading said current paging-related message, wherein said paging-related message is received during said time period.

17. The apparatus of claim 16, wherein said device comprises at least one of said path searcher and said rake receiver.

18. The apparatus of claim 12, wherein said communication system comprises a WCDMA system.

19. A method for detecting a periodic message in a mobile communication system, comprising the steps of:

initiating a reception of synchronization data a predetermined amount of time prior to a current periodic message, said predetermined amount of time based on at least one of an estimated signal-to-noise ratio (SNR) from at least one prior periodic message, an estimated error in said at least one prior periodic message, and an estimated radio path profile from at least one prior periodic message;

using said synchronization data to achieve synchronization; and

detecting said current periodic message based on said synchronization.

20. The method of claim 19, wherein said step of using said synchronization data comprises at least one of correcting a carrier frequency and estimating radio channel characteristics.

21. The method of claim 19, further comprising the step of stopping the reception of said synchronization data a predetermined amount of time subsequent to said current periodic message, said predetermined amount of time subsequent to said current periodic message based on at least one of said estimated SNR from said at least one prior periodic message, said estimated error in said at least one prior periodic message, and said estimated radio path profile from said at least one prior periodic message.

22. The method of claim 21, wherein said current periodic message and said at least one prior periodic message comprise paging messages.

23. The method of claim 22, wherein said current paging message comprises a paging indicator message.

24. The method of claim 23, wherein, if said paging indicator message indicates a page, said method further comprising the steps of:

initiating a reception of new synchronization data a predetermined amount of time prior to a paging data message, said predetermined amount of time prior to said paging data message based on at least one of an estimated signal-to-noise ratio, estimated channel characteristics, an estimated paging detection error, and an estimated radio path profile;

refining said synchronization using the received new synchronization data; and

detecting said paging data message.