METHOD OF CONTROLLING CELL SELECTION FOR A WIRELESS COMMUNICATION SYSTEM AND RELATED DEVICE

• US 20100075670A1
• Filed: 09/22/2008
• Published: 03/25/2010
• Est. Priority Date: 09/22/2008
• Status: Active Grant

• Current Assignee: HTC Corporation
• Original Assignee: HTC Corporation
• Inventors: Wu, Chih-Hsiang
• Granted Patent: US 8,666,410 B2
• Time in Patent Office: Days
• US Class Current: 455/434
• CPC Class Codes: H04J 11/0093 Neighbour cell search
• CPC Class Codes: H04W 36/0061 of neighbour cell information
• CPC Class Codes: H04W 48/02 Access restriction performed under specific conditions
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service
• CPC Class Codes: H04W 48/20 Selecting an access point

Abstract

A method of controlling CSG, known as closed subscriber group, cell selection for a wireless communication system is provided. The wireless communication system includes a network and a user equipment including a whitelist capable of providing a list of accessible CSG cells. The method includes updating the whitelist when the user equipment subscribes to a CSG cell that is not included in the whitelist or does not subscribe to a CSG cell in the whitelist.

Claims

1. A method of controlling closed subscriber group, hereinafter called CSG, cell selection for a user equipment, hereinafter called UE, used in a wireless communication system comprising a network, the UE comprising a whitelist capable of providing a list of accessible CSG cells, the method comprising:

updating the whitelist when the UE subscribes to a CSG cell that is not included in the whitelist or does not subscribe to a CSG cell in the whitelist.

2. The method of claim 1, wherein the whitelist is updated by adding the CSG cell that is not included in the whitelist when the UE subscribes to the CSG cell that is not included in the whitelist.

3. The method of claim 2, wherein the CSG cell that is not included in the whitelist is manually added to the whitelist.

4. The method of claim 2, wherein adding the CSG cell that is not included in the whitelist comprises:

receiving a detach message with a re-attach request from the network;

initiating a attach procedure in response to the re-attach request;

through the attach procedure, receiving an ATTACH ACCEPT message from the network, the ATTACH ACCEPT message comprising an up-to-date whitelist comprising the CSG cell that is not included in the whitelist; and

adding the CSG cell that is not included in the whitelist to the whitelist according to the up-to-date whitelist.

5. The method of claim 2, wherein adding the CSG cell that is not included in the whitelist comprises:

receiving a message from the network to add the CSG cell that is not included in the whitelist to the whitelist.

6. The method of claim 5, wherein the message is a short message service message (SMS), a CM SERVICE REJECT message, a SERVICE REJECT message, a ATTACH REJECT message, a TRACKING AREA UPDATE REJECT message, a ROUTING AREA UPDATE REJECT message or a LOCATION UPDATING REJECT message.

7. The method of claim 5, wherein the message is used in a non-access-stratum, abbreviated to NAS, function of system architecture evolution, abbreviated to SAE, for a long term evolution, abbreviated to LTE wireless system.

8. The method of claim 1, wherein the whitelist is updated by removing the CSG cell in the whitelist when the UE does not subscribe to the CSG cell in the whitelist.

9. The method of claim 8, wherein the CSG cell in the whitelist is manually removed from the whitelist.

10. The method of claim 8, wherein removing the CSG cell in the whitelist comprises:

receiving a detach message with a re-attach request from the network;

initiating an attach procedure in response to the re-attach request;

through the attach procedure, receiving an ATTACH ACCEPT message from the network, the ATTACH ACCEPT message comprising an up-to-date whitelist excluding the CSG cell in the whitelist; and

removing the CSG cell in the whitelist according to the up-to-date whitelist.

11. The method of claim 8, wherein removing the CSG cell in the whitelist comprises:

receiving a message from the network; and

removing the CSG cell in the whitelist according to the message.

12. The method of claim 11, wherein the message is a short message service message (SMS), a CM SERVICE REJECT message, a SERVICE REJECT message, a ATTACH REJECT message, a TRACKING AREA UPDATE REJECT message, a ROUTING AREA UPDATE REJECT message or a LOCATION UPDATING REJECT message.

13. The method of claim 11, wherein the message is used in a non-access-stratum, abbreviated to NAS, function of system architecture evolution, abbreviated to SAE, for a long term evolution, abbreviated to LTE, wireless system.

14. A method of controlling closed subscriber group, hereinafter called CSG, cell selection for a user equipment of a wireless communication system, the user equipment comprising a whitelist providing a list of accessible CSG cells, the method comprising:

periodically searching the CSG cells in the whitelist according to a searching period when the user equipment camps on a macro cell and does not meet any of measurement criteria for CSG cell measurement.

15. The method of claim 14, further comprising configuring the searching period with a network signaling message.

16. The method of claim 15, wherein the network signaling message is at least one of an ATTACH ACCEPT message and a TRACKING AREA UPDATE ACCEPT message.

17. The method of claim 14, further comprising storing a configured parameter of the searching period in at least one of a subscriber identity module and a flash memory.

18. The method of claim 14, wherein the macro cell is a macro cell of a GSM EDGE radio access network, hereinafter called GERAN, a UMTS radio access network, hereinafter called UTRAN, or an evolved UTRAN.

19. The method of claim 18, further comprising configuring the searching period with a shot message service message (SMS) when the UE camps on the GERAN or UTRAN.

20. The method of claim 14, wherein the searching period is about 5 minutes.

21. The method of claim 14 further comprising stopping periodically searching the CSG cells listed in the whitelist according to a network signaling message.

22. The method of claim 21, further comprising removing all of the CSG cells listed in the whitelist by the network signaling message.

23. A method of controlling CSG cell selection for a user equipment of a wireless communication system, the user equipment comprising a whitelist capable of providing a list of accessible CSG cells, the method comprising:

performing CSG cell searching when a new CSG cell is added to the whitelist.

24. The method of claim 23 further comprising stopping the CSG cell searching when the CSG cell searching is done once and the CSG cell cannot be found.

25. A method of controlling CSG cell selection for a user equipment (UE) of a wireless communication system, the UE comprising a whitelist capable of providing a list of accessible CSG cells, the method comprising:

performing cell selection to select a cell to camp on when a CSG cell that the UE currently camps on is removed from the whitelist.

26. A method of controlling CSG cell selection for a user equipment, hereinafter called UE, used in a wireless communication system with a network, the UE comprising a whitelist capable of providing a list of accessible CSG cells, the method comprising:

receiving a paging message from the network when the UE camps on a CSG cell in the whitelist and does not subscribe to the CSG cell;

initiating a service request procedure when the paging message is received;

through the service request procedure, receiving a SERVICE REJECT message comprising a reject cause value from the network; and

searching a cell other than the CSG cell when the reject cause value of the SERVICE REJECT message is received.

27. The method of claim 26, wherein the reject cause value is 15.

28. The method of claim 26, wherein the CSG cell belongs to a first defined area, and the UE searching the cell other than the CSG cell when the reject cause value of the SERVICE REJECT message is received comprises:

searching the cell in a second defined area.

29. The method of claim 28 further comprising:

initiating an area update procedure when the cell in the second defined area is searched and found;

through the area update procedure, receiving a first message from the network, the first message comprises an up-to-date whitelist excluding the CSG cell in the whitelist; and

removing the CSG cell from the whitelist according to the up-to-date whitelist.

30. The method of claim 29, wherein the first defined area is a tracking area, a routing area or a location area, the second defined area is a tracking area, a routing area or a location area, the area update procedure is a tracking area update procedure, a location area update procedure or a routing area update procedure, and the first message is a TRACKING AREA UPDATE ACCEPT message, a LOCATION UPDATING ACCEPT message, or a ROUTING AREA UPDATE ACCEPT message.

31. The method of claim 29, wherein the second defined area is a location area of a GSM/EDEG radio access network or a UMTS radio access network in a same public land mobile network as the first defined area, the area update procedure is a location area update procedure or a routing area update procedure, and the first message is a LOCATION UPDATE ACCEPT message or a ROUTING AREA UPDATE ACCEPT message.