Method and mobile device for performing fast hand-over in WLAN and method of switching services using GPS information

• US 20070025293A1
• Filed: 01/10/2006
• Published: 02/01/2007
• Est. Priority Date: 07/27/2005
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Choi, Hyong-uk
• Granted Patent: US 8,897,777 B2
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04W 36/00835 Determination of neighbour cell lists
• CPC Class Codes: H04W 36/0085 Hand-off measurements
• CPC Class Codes: H04W 36/32 by location or mobility data, e.g. speed data
• CPC Class Codes: H04W 36/322 by location data
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A fast hand-over method of a mobile device roaming in a wireless LAN environment includes: receiving GPS information; based on the received location information of the mobile device, searching one or more APs; by scanning the searched APs, detecting an AP to reassociate with; and reassociating with the detected AP. According to the method, when roaming in a wireless LAN environment, a mobile device calculates a moving path by using GPS information and then, by scanning only APs belonging to channels allocated to areas related to the moving direction, the mobile device can reduce a hand-over period, and as a result, a QoS guaranteed service can be provided continuously. Also, by using GPS information, the mobile device can selectively switch to an optimum network service in an area to which different network services are applied.

Claims

1. A hand-over method of a mobile device roaming in a wireless local area network (LAN) environment, the method comprising:

receiving global positioning system (GPS) information of the mobile device;

based on the received GPS information of the mobile device, searching at least one access point (AP) other than the existing AP to which the mobile device is currently connected;

by scanning the searched AP, detecting an AP to reassociate with; and

reassociating the mobile device with the detected AP.

2. The method of claim 1, wherein the searching of the at least one AP comprises:

estimating a moving direction or moving path of the mobile device by using a plurality of GPS information items; and

obtaining information on at least one AP included in a predetermined range on the basis of the moving direction or moving path, from a channel table including location information of APs on a plurality of channels.

3. The method of claim 1, wherein the detecting of the AP comprises:

generating a list including obtained AP information;

updating an existing scanning channel list with the generated list; and

detecting an AP to be reassociated with, by scanning the APs of the updated channel list.

4. The method of claim 2, wherein the predetermined range is classified into a first level including APs on all channels, a second level including APs on channels within a first angle relative to the estimated moving direction or path, a third level including APs on channels within a second angle relative to the estimated moving direction or path and which is less than the first angle, and a fourth level including an AP within a narrowest angle relative to the estimated moving direction or moving path of the mobile device.

5. The method of claim 1, wherein the searching of at least one AP includes searching the AP belonging to a range of a fourth level selected from first through fourth levels of fields of view.

6. The method of claim 1, wherein the searching of at least one AP includes searching the APs belonging to a range of the third level selected from first through fourth levels of fields of view.

7. The method of claim 1, wherein the searching of at least one AP includes searching the APs belonging to a range of the second level selected from first through fourth levels of fields of view.

8. The method of claim 1, wherein the searching of at least one AP and detecting the AP comprise:

searching the AP of a fourth level on the basis of the estimated moving direction or moving path of the mobile device;

if as the result of the scanning the AP of the fourth level, a matching AP is not detected, searching the APs belonging to a third level other than the fourth level;

if as the result of the scanning the APs of the third level other than the fourth level, a matching AP is not detected, searching the APs belonging to a second level other than the third level; and

if as the result of the scanning the APs of the second level, a matching AP is not detected, searching the APs belonging to a first level other than the second level.

9. The method of claim 2, wherein each of AP related information items stored in the channel table comprises a basic service set (BSS) ID, an AP address, channel information, GPS information of the AP or combinations thereof.

22. The method of claim 2, wherein the detecting of the AP comprises:

generating a list including the obtained AP information;

updating an existing scanning channel list with the generated list; and

detecting an AP to be reassociated with, by scanning the APs of the update channel list.

23. The method of claim 4, wherein the searching of at least one AP includes searching the AP belonging to the range of the fourth level.

24. The method of claim 4, wherein the searching of at least one AP includes searching the APs belonging to the range of the third level.

25. The method of claim 4, wherein the searching of at least one AP includes searching the APs belonging to the range of the second level.

26. The method of claim 4, wherein the searching of at least one AP and detecting the AP comprise:

searching the AP of the fourth level on the basis of the moving direction or moving path of the mobile device;

if as the result of the scanning the AP of the fourth level, a matching AP is not detected, searching the APs belonging to the third level;

if as the result of the scanning the APs of the third level, a matching AP is not detected, searching the APs belonging to the second level; and

if as the result of the scanning the APs of the second level, a matching AP is not detected, searching the APs belonging to the first level.

10. A mobile device performing hand-over when roaming in a wireless local area network (LAN) environment comprising:

a receiving unit receiving global positioning system (GPS) information of the mobile device;

an access point (AP) searching unit searching at least one AP other than an existing AP to which the mobile device is connected, based on the received GPS information of the mobile device;

a detecting unit detecting an AP to reassociate with, by scanning the at least one searched AP; and

a reassociating unit reassociating the mobile device with the detected AP.

11. The mobile device of claim 10, wherein the AP search unit comprises:

an estimating unit estimating a moving direction or moving path of the mobile device by using a plurality of GPS information of the mobile device;

a memory storing channel table including GPS information of APs on a plurality of channels; and

a unit obtaining information on at least one AP included in a predetermined range on the basis of the moving direction or moving path, from the channel table.

12. The mobile device of claim 10, wherein the AP detecting unit generates a list including the obtained AP information, updates an existing scanning channel list with the generated list, and detects an AP to be reassociated with, by scanning the APs of the update channel list.

13. The mobile device of claim 11, wherein the predetermined range is classified into a first level including APs on all channels, a second level including APs on channels within a first angle relative to the moving direction or path, a third level including APs on channels within a second angle relative to the moving direction or path less than the first angle, and a fourth level including an AP within a narrowest angle in the moving direction or moving path of the mobile device.

14. The mobile device of claim 10, wherein the AP search unit searches the AP belonging to a range of a fourth level selected from first through fourth levels.

15. The mobile device of claim 10, wherein the AP search unit searches the APs belonging to a range of a third level selected from first through fourth levels.

16. The mobile device of claim 10, wherein the AP search unit searches the APs belonging to a range of a second level selected from first through fourth levels.

17. The mobile device of claim 10, wherein the AP search unit and the AP detection unit:

search the AP of a fourth level on the basis of the moving direction or moving path of the mobile device;

if as the result of the scanning the AP of the fourth level, a matching AP is not detected, search the APs belonging to a third level other than the fourth level;

if as the result of the scanning the APs of the third level, a matching AP is not detected, search the APs belonging to a second level other than the third level; and

if as the result of the scanning the APs of the second level, a matching AP is not detected, search the APs belonging to a first level other than the second level.

18. The mobile device of claim 11, wherein the channel table includes a basic service set (BSS) ID, an AP address, channel information, GPS information of the AP or combinations thereof.

27. The mobile device of claim 11, wherein the unit detecting an AP to reassociate with, by scanning the at least one searched AP, generates a list including the obtained AP information, updates an existing scanning channel list with the generated list, and detects an AP to be reassociated with, by scanning the APs of the update channel list.

28. The mobile device of claim 13, wherein the AP search unit searches the AP belonging to the range of the fourth level.

29. The mobile device of claim 13, wherein the AP search unit searches the APs belonging to the range of the third level.

30. The mobile device of claim 13, wherein the AP search unit searches the APs belonging to the range of the second level.

31. The mobile device of claim 13, wherein the AP search unit and the AP detection unit search the AP of the fourth level on the basis of the moving direction or moving path of the mobile device;

if as the result of the scanning the AP of the fourth level, a matching AP is not detected, search the APs belonging to the third level;

if as the result of the scanning the APs of the third level, a matching AP is not detected, search the APs belonging to the second level; and

if as the result of the scanning the APs of the second level, a matching AP is not detected, search the APs belonging to the first level.

19. A method of switching services of a mobile device comprising:

obtaining current location information of the mobile device through a global positioning system (GPS) receiver;

based on the obtained current location information of the mobile device, recognizing at least one network service receivable by the mobile device at the current location;

if the number of the recognized network services is two or more, selecting one of the recognized network services according to a predetermined condition; and

switching to the selected network service.

20. The method of claim 19, wherein the recognizing of the network services includes searching network services being provided at the current location of the mobile device from a database in the mobile device, which stores types of a variety of networks and applied areas in advance.

21. The method of claim 19, wherein the predetermined condition is set in terms of a most efficient price of unit-service of services.

32. A hand-over method of a mobile device roaming in a wireless network environment, the method comprising:

detecting positional information indicating a movement of the mobile device relative to one access point to which the mobile device is connected;

anticipating another access point to which the mobile device connectable according to the indicated movement and a table storing a location of the another access point; and

reassociating the mobile device with the anticipated another access point.

33. A wireless access point comprising:

a wireless connection unit which receives wirelessly transmitted information with respect to a device;

a network unit which communicates with at least one other access point; and

a controller which receives an association request from the device received at the wireless connection unit and which is requesting data service with respect to the access point, transmits through the network unit a request for a quality of service (QoS) connection from the at least one other access point to which the device is currently QoS connected, receives through the network unit a QoS response from the at least one other access point, and, after receiving the QoS response, provides the requested data service to the device using the wireless connection unit according to the QoS connection.

34. A wireless access point comprising:

a wireless connection unit which receives wirelessly transmitted information with respect to a device;

a network unit which communicates with at least one other access point; and

a controller which provides through the wireless connection unit a quality of service (QoS) connection with respect to the device, receives through the network unit a request for a quality of service (QoS) connection from the at least one other access point to which the device is requesting to be QoS connected, transmits through the network unit a QoS response to the at least one other access point, and, after transmitting the QoS response, terminates the QoS connection with the device.

35. A mobile device performing hand-over when roaming in a wireless network environment, comprising:

a wireless communication unit transmitting data with respect to one access point (AP) and which is capable of communicating with another AP; and

a controller which determines a motion of the mobile device relative to the one AP, retrieves location information on the another AP based on the determined motion, and uses the wireless communication unit to reassociate the mobile device with the another AP and disconnect the mobile device from the one AP while maintaining a quality of service (QoS) connection.