Scanning cell-dependent groups of profiles of wireless local area networks

• US 7,844,269 B2
• Filed: 01/22/2007
• Issued: 11/30/2010
• Est. Priority Date: 01/22/2007
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Research In Motion Limited (Blackberry Limited)
• Inventors: Abdel-Kader, Sherif
• Primary Examiner(s): Cho; Un C
• Application Number:
  US11/625,419
• Publication Number:
  US 20080176579A1
• Time in Patent Office: 1,408 Days
• Field of Search: 455/432.3, 455/435.1, 455/435.2, 455/435.3, 455/432.1, 455/443, 455/444, 455/448, 455/41.2, 455/574, 370/328, 370/338
• US Class Current: 455/435.2
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 52/0258 controlling an operation mode according to history or models of usage information, e.g. activity schedule or time of day
• CPC Class Codes: H04W 8/183 Processing at user equipment or user record carrier
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A wireless device capable of wireless local area network (WLAN) communications and cellular network communications stores profiles of wireless local area networks. The device identifies in which cell of a cellular network the device is currently located, and then scans more frequently for wireless local area networks matching profiles to which, previously, the device has connected while located in the cell, than for wireless local area networks matching other profiles.

Claims

1. A method for scanning for wireless local area networks, the method comprising:

storing profiles of wireless local area networks in a device;

identifying via a wireless wide area network interface of the device in which cell of a cellular network the device is currently located; and

scanning via a wireless local area network (WLAN) interface of the device for wireless local area networks matching stored profiles to which, previously, the device has connected while located in the cell and for wireless local area networks matching other stored profiles, such that scanning for wireless local area networks matching stored profiles to which, previously, the device has connected while located in the cell occurs more frequently than scanning for wireless local area networks matching the other stored profiles.

2. The method of claim 1, wherein scanning more frequently comprises:

scanning once per each sleep interval for wireless local area networks matching profiles to which, previously, the device has connected while located in the cell; and

scanning once per each other sleep interval for wireless local area networks matching the other profiles.

3. The method of claim 1, further comprising:

maintaining for the cell records on a per-profile basis of the number of times the device has connected to wireless local area networks matching profiles stored in the device while located in the cell.

4. The method of claim 3, further comprising:

partitioning profiles stored in the device into two or more groups based on whether a record for a profile is maintained for the cell and the number of times the device was located in the cell and connected to a wireless local area network matching the profile identified in the record, each group having associated therewith a fixed number of sleep intervals,

wherein scanning more frequently comprises scanning after a J-th sleep interval for wireless local area networks matching profiles in those particular groups where J mod M equals zero and M is the fixed number of sleep intervals associated with that particular group.

5. The method of claim 4, wherein scanning after a J-th sleep interval comprises:

scanning profiles in those particular groups in order of increasing M and within each of those particular groups, by priority of the profile.

6. The method of claim 1, wherein scanning more frequently comprises:

scanning according to a first set of one or more sleep interval durations for wireless local area networks matching profiles to which, previously, the device has connected while located in the cell; and

scanning according to a second set of one or more sleep interval durations for wireless local area networks matching the other profiles,

wherein each sleep interval duration in the first set is shorter than its corresponding sleep interval duration in the second set.

7. The method of claim 1, wherein scanning more frequently comprises:

scanning according to a first set of one or more sleep interval durations for wireless local area networks matching profiles to which, previously, the device has connected at least a certain number of times while located in the cell; and

scanning according to a second set of one or more sleep interval durations for wireless local area networks matching profiles to which, previously, the device has connected at least once and fewer than said certain number of times while located in the cell; and

scanning according to a third set of one or more sleep interval durations for wireless local area networks matching the other profiles,

wherein each sleep interval duration in the first set is shorter than its corresponding sleep interval duration in the second set, and wherein each sleep interval duration in the second set is shorter than its corresponding sleep interval duration in the third set.

8. A wireless device comprising:

a processor;

a wireless local area network (WLAN) interface coupled to the processor;

a wireless wide area network interface coupled to the processor; and

a memory coupled to the processor, the memory arranged to store profiles of wireless local area networks and arranged to store code which, when executed by the processor, identifies via the wireless wide area network interface of the device in which cell of a cellular network the device is currently located and causes the WLAN interface to scan via the wireless local area network interface of the device for wireless local area networks matching stored profiles to which, previously, the device has connected while located in the cell and for wireless local area networks matching other stored profiles, such that scanning for wireless local area networks matching stored profiles to which, previously, the device has connected while located in the cell occurs more frequently than scanning for wireless local area networks matching other stored profiles.

9. The wireless device of claim 8, wherein the code, when executed by the processor, causes the WLAN interface to scan once per sleep interval for wireless local area networks matching profiles to which, previously, the device has connected while in the cell, and causes the WLAN interface to scan once per each other sleep interval for wireless local area networks matching the other profiles.

10. The wireless device of claim 8, wherein the code, when executed by the processor, maintains for the cell records on a per-profile basis of the number of times the device has connected to wireless local area networks matching profiles stored in the device while located in the cell.

11. The wireless device of claim 10, wherein the code, when executed by the processor, partitions profiles stored in the device into two or more groups based on whether a record for a profile is maintained for the cell and the number of times the device was located in the cell and connected to a wireless local area network matching the profile identified in the record, each group having associated therewith a fixed number of sleep intervals, and scans after a J-th sleep interval for wireless local area networks matching profiles in those particular groups where J mod M equals zero and M is the fixed number of sleep intervals associated with that particular group.

12. A non-transitory computer readable medium storing instructions which, when executed by a processor of a wireless device having a wireless local area network (WLAN) interface and a wireless wide area network interface, result in the device identifying via the wireless wide area network interface of the device in which cell of a cellular network the device is currently located and causing the WLAN interface to scan via the wireless local area network interface of the device for wireless local area networks matching stored profiles to which, previously, the device has connected while located in the cell and for wireless local area networks matching other stored profiles, such that scanning for wireless local area networks matching stored profiles to which, previously, the device has connected while located in the cell occurs more frequently than scanning for wireless local area networks matching other stored profiles.

13. The non-transitory computer readable medium of claim 12 wherein the code, when executed by the processor, further results in scanning once per sleep interval for wireless local area networks matching profiles to which, previously, the device has connected while in the cell, and scanning once per each other sleep interval for wireless local area networks matching the other profiles.

14. The non-transitory computer readable medium of claim 12, wherein the code, when executed by the processor, further results in maintaining for the cell records on a per-profile basis of the number of times the device has connected to wireless local area networks matching profiles stored in the device while located in the cell.

15. The non-transitory computer readable medium of claim 14, wherein the code, when executed by the processor, further results in partitioning profiles stored in the device into two or more groups based on whether a record for a profile is maintained for the cell and the number of times the device was located in the cell and connected to a wireless local area network matching the profile identified in the record, each group having associated therewith a fixed number of sleep intervals, and scanning after a J-th sleep interval for wireless local area networks matching profiles in those particular groups where J mod M equals zero and M is the fixed number of sleep intervals associated with that particular group.