REDUCED SCANNING WITHIN A UNIFORM PERIOD IN OUT-OF-SERVICE CONDITIONS

• US 20080220762A1
• Filed: 03/07/2007
• Published: 09/11/2008
• Est. Priority Date: 03/07/2007
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Declerck, Daniel J., Welnick, William E.
• Granted Patent: US 8,019,340 B2
• Time in Patent Office: Days
• US Class Current: 455/422.1
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 4/00 Services specially adapted for wireless communication networks; Facilities therefor
• CPC Class Codes: H04W 52/0241 where no transmission is received, e.g. out of range of the transmitter
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method (300) and mobile device (120) for reduced scanning within a uniform period in an out-of-service condition is described herein. In one arrangement, the method can include the steps of detecting (310) the out-of-service condition, during a wake-up interval (410), waking (314) up to scan one or more channels (510, 520, 530, 540) for service and maintaining a constant wake-up time for subsequent wake-up intervals. The method can also include the step of varying (320) the amount of time spent scanning the channels during the subsequent wake-up intervals. As an example, varying the amount of time spent scanning channels can be done by decreasing (322) the amount of time spent scanning for each successive, subsequent wake-up interval.

Claims

1. A method for reduced scanning within a uniform period in an out-of-service condition, comprising:

detecting the out-of-service condition;

during a wake-up interval, waking up to scan one or more channels for service;

maintaining a constant wake-up time for subsequent wake-up intervals; and

varying the amount of time spent scanning the channels during the subsequent wake-up intervals.

2. The method according to claim 1, wherein varying the amount of time spent scanning channels comprises decreasing the amount of time spent scanning for each successive, subsequent wake-up interval.

3. The method according to claim 2, further comprising decreasing the amount of time spent scanning for each successive, subsequent wake-up interval until a fixed minimal scanning time is reached.

4. The method according to claim 2, wherein the channels are voice-optimized channels or data-optimized channels and wherein waking up to scan one or more channels for service comprises scanning a first scan list containing the voice-optimized channels for a predetermined number of times or scanning a predetermined number of the data-optimized channels, which are part of a second scan list.

5. The method according to claim 4, wherein decreasing the amount of time spent scanning for each successive, subsequent wake-up interval comprises reducing the predetermined number of times the first scan list is scanned or the predetermined number of data-optimized channels of the second scan list that are scanned for each successive, subsequent wake-up interval.

6. The method according to claim 5, wherein the first scan list and the second scan list are derived from a preferred roaming list.

7. The method according to claim 4, wherein the predetermined number of times the first scan list is scanned is based on the number of voice-optimized channels in the first scan list.

8. The method according to claim 1, wherein the time spent scanning during the wake-up interval takes up at most approximately ninety percent of the wake-up interval.

9. A mobile device that reduces scanning within a uniform period in an out-of-service condition, comprising:

a transceiver that receives wireless signals from a communication network; and

a processor that is coupled to the transceiver, wherein the processor;

detects that the transceiver is in the out-of-service condition with the communication network;

determines a wake-up interval and a constant wake-up time for the transceiver such that the transceiver will wake up on a substantially uniform basis to scan one or more channels for service; and

varies the amount of time that the transceiver will spend scanning the channels for subsequent wake-up intervals.

10. The mobile device according to claim 9, wherein the processor varies the amount of time that the transceiver will spend scanning by decreasing the amount of time that the transceiver will spend scanning for each successive, subsequent wake-up interval.

11. The mobile device according to claim 10, wherein the processor continues to decrease the amount of time that the transceiver spends scanning for each successive, subsequent interval until a fixed minimal scanning period is reached.

12. The mobile device according to claim 10, further comprising a memory that is coupled to the processor, wherein the memory stores a first scan list containing voice-optimized channels and a second scan list containing data-optimized channels and the transceiver, during the wake-up interval, scans the first scan list a predetermined number of times or the data-optimized channels of the second scan list a predetermined number of times based on a scan list multiplier.

13. The mobile device according to claim 12, wherein the transceiver decreases the amount of time that the transceiver will spend scanning for each successive, subsequent wake-up interval by reducing the scan list multiplier for each successive, subsequent wake-up interval.

14. The mobile device according to claim 13, wherein the first scan list and the second scan list are derived from a preferred roaming list.

15. The mobile device according to claim 14, wherein the scan list multiplier is based on the number of voice-optimized channels in the first scan list.

16. The mobile device according to claim 9, wherein the transceiver spends at most approximately ninety percent of the duration of the wake-up interval scanning for service.

17. A machine readable storage having stored thereon a computer program having a plurality of code sections executable by a mobile device for causing the mobile device to perform the steps of:

detecting an out-of-service condition at the mobile device;

determining a wake-up interval for the mobile device;

during the wake-up interval, waking up the mobile device to scan one or more channels for service;

maintaining a uniform wake-up time for the mobile device for subsequent wake-up intervals; and

varying the amount of time that the mobile device spends scanning the channels for service during the subsequent wake-up intervals.

18. The machine readable storage according to claim 17, wherein the computer program also causes the mobile device to vary the amount of time that the mobile device spends scanning for service during the subsequent wake-up intervals by reducing the time spent scanning for service during successive, subsequent wake-up intervals.

19. The machine readable storage according to claim 18, wherein the computer program also causes the mobile to perform the step of reducing the time spent scanning for service during successive, subsequent wake-up intervals until a fixed minimal scanning time is reached.

20. The machine readable storage according to claim 18, wherein the computer program also causes the mobile device to scan the channels for service by scanning a scan list stored in the mobile device, wherein the scanning of the scan list is based on a scan list multiplier.

21. The machine readable storage according to claim 20, wherein the computer program also causes the mobile device to reduce the amount of time spent scanning the scan list during successive, subsequent wake-up intervals by reducing the scan list multiplier for each successive, subsequent wake-up interval.

22. A method of reduced scanning, comprising:

in response to an out-of-service condition, determining a wake-up interval that designates when a mobile device will wake-up at a uniform rate;

when the mobile device wakes up, scanning one or more channels of a scan list for service; and

reducing the amount of time that the mobile device spends scanning the scan list for each successive wake-up interval until fixed minimal scanning time is reached, while maintaining the uniform wake-up rate of the mobile device.