METHOD AND ARRANGEMENT IN A TELECOMMUNICATION SYSTEM

• US 20090092097A1
• Filed: 05/23/2008
• Published: 04/09/2009
• Est. Priority Date: 10/03/2007
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Vikberg, Jari Tapio, Buchmayer, Mats, Hedberg, Tomas, NYLANDER, Tomas
• Granted Patent: US 8,243,682 B2
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04J 11/0069 Cell search, i.e. determining cell identity [cell-ID] design of multiplexing codes H04J13/00; processing access restriction or access information H04W48/16; discovery of network devices for network data management H04W8/005; sounding signals for channel estimation H04L25/0226; structure of reference signals in multicarrier modulation systems H04L27/2613; frame, time or carrier synchronisation in multicarrier modulation systems H04L27/2655
• CPC Class Codes: H04W 36/0061 of neighbour cell information
• CPC Class Codes: H04W 36/04 Reselecting a cell layer in multi-layered cells
• CPC Class Codes: H04W 48/02 Access restriction performed under specific conditions

Abstract

The described technology generally relates to method(s) and arrangement(s) for access control during relocation of a user equipment (UE) into a femto base station (FBS) and dynamic triggering of the relocation into the FBS. A white list is maintained in the UE. The white list includes information on a list of FBSs that the UE is allowed to relocate. The UE detects a target FBS and reports target FBS to a source macro base station (MBS). The source MBS makes a relocation request to a mobility controller. The mobility controller grants or denies the requests or allows the target FBS to make the decision. Upon grant, the UE is relocated to the target FBS. Otherwise, the white list is updated in the UE.

Claims

1. A method to perform a relocation of a user equipment (UE) from a source macro base station (MBS) to a target femto base station (FBS), comprising:

detecting the target FBS based on a white list of the UE;

reporting the target FBS to the source MBS;

receiving a command from the source MBS;

relocating so that the UE is handed over from the source MBS to the target FBS when the command from the source MBS is to relocate the UE,

wherein the white list includes information on one or more femto base stations available to provide connectivity to the UE including a short identity and a long identity for each of the one or more femto base stations,

wherein the long identity uniquely identifies each femto base station and the short identity non-uniquely identifies each femto base station, and

wherein in the act of detecting the target FBS, the target FBS is detected based on the short and the long identities of the target FBS.

2. The method of claim 1, further comprising:

updating the white list of the UE to modify information regarding the target FBS to indicate that the UE is not allowed to access the target FBS when the command from the source MBS is to update the white list.

3. The method of claim 1, wherein the acts of detecting and reporting the target FBS comprise:

determining whether there are possible femto base stations for the relocation of the UE based on the white list;

identifying a femto base station as the target FBS when it is determined that there are possible femto base stations for the relocation;

determining whether the relocation to the target FBS Is allowable after identifying the target FBS; and

reporting the long identity of the target FBS to the source MBS when it is determined that the relocation to the target FBS is allowable.

4. The method of claim 3, wherein the act of determining whether there are possible femto base stations for the relocation of the UE is based on one or more of:

a presence of a base station with a short identity that is listed in the white list as being a femto base station,

the source MBS being listed in the white list as having a macro cell that over lays one or more femto cell areas corresponding to one or more femto base stations,

a timing advance of the source MBS matching one or more timing advances in the white list,

a location of the UE being within a predetermined distance of one or more femto base stations in the white list, and

a current time matching within a predetermined tolerance of one or more normal access times listed for one or more femto base station in the white list.

5. The method of claim 3, wherein the acts of identifying the target FBS and determining whether the relocation to the target FBS is allowable comprise:

retrieving the short identity of a detected femto base station;

determining whether the relocation to the detected femto base station is possible based on the short identity;

retrieving the long identity of the detected femto base station when it is determined that the relocation to the detected femto base station is possible based on the short identity;

determining whether the relocation to the detected femto base station is possible based on the long identity; and

reporting the long identity of the detected femto base station as the target FBS to the source MBS when it is determined that the relocation to the detected femto base station is possible based on the long identity.

6. The method of claim 5, wherein the acts of retrieving the short identity of the detected femto base station and determining whether the relocation to the detected femto base station based on the short identity is possible comprise:

requesting the source MBS for a short gap;

receiving a grant of the short gap from the source MBS;

reading the short identity of the detected femto base station during the short gap after receiving the grant of the short gap; and

determining whether the read short identity is in the white list and determining that the relocation is possible when the short identity is in the white list and not possible otherwise,

wherein the short gap is a time slot in which the source MBS will not transmit data to the UE to allow the UE to read the short identity transmitted by the detected femto base station.

7. The method of claim 6, wherein the acts of retrieving the long identity of the detected femto base station and determining whether the relocation to the detected femto base station based on the short identity is possible comprise:

requesting the source MBS for a long gap;

receiving a grant of the long gap from the source MBS;

reading the long identity of the femto base station during the long gap after receiving grant of the long gap; and

determining whether the read long identity is in the white list and determining that the relocation is possible when the long identity is in the white list and not possible otherwise,

wherein the long gap is a time slot in which the source MBS will not transmit data to the UE to allow the UE to read the long identity transmitted by the femto base station, and

wherein a duration of the long gap is longer than a duration of the short gap.

8. The method of claim 3, wherein the acts of identifying the target FBS and determining whether the relocation to the target FBS is allowable comprise:

determining whether the target FBS and the source MBS are on a same carrier;

requesting the source MBS for a long gap when it is determined that the target FBS and the source MBS are on the same carrier;

receiving a grant of the long gap from the source MBS;

reading the long identity of the target FBS during the long gap after receiving the grant of the long gap; and

determining whether the read long identity is in the white list and determining that the relocation is possible when the long identity is in the white list and not possible otherwise,

wherein the long gap is a time slot in which the source MBS will not transmit data to the UE to allow the UE to read the long identity transmitted by the target FBS.

9. The method of claim 3, wherein the acts of identifying the target FBS and determining whether the relocation to the target FBS is allowable comprise:

determining whether the UE is a dual-receiver UE;

reading the long identity transmitted by the target FBS; and

determining whether the read long identity is in the white list and determining that the relocation is possible when the long identity is in the white list and not possible otherwise.

29. The method of claim 3, wherein the act of determining whether there are possible femto base stations for the relocation of the UE is triggered in response to a manual operation by a user and/or automatically on a periodic basis.

30. The method of claim 3, wherein a short range wireless protocol signal is utilized in the act of determining whether there are possible femto base stations for the relocation of the UE.

31. The method of claim 9, wherein the long identity transmitted by the target FBS is transmitted on a 3GPP radio signal different from a 3GPP radio signal transmitted by the source MBS or is transmitted on a short range wireless protocol signal.

10. A user equipment (UE), comprising:

a radio communications unit arranged to communicate with a source macro base station (MBS) and a target femto base station (FBS) in a network;

a storage unit arranged to store a white list; and

a processing unit arranged to trigger a relocation of the UE from the source MBS to the target FBS,

wherein the processing unit is arranged to;

detect the target FBS based on the white list,

report the target FBS to the source MBS,

receive a command from the source MBS,

relocate so that the UE is handed over from the source MBS to the target FBS when the command from the source MBS is to relocate the UE,

wherein the white list in the storage unit includes information on one or more femto base stations available to provide connectivity to the UE including a short identity and a long identity for each of the one or more femto base stations,

wherein the long identity uniquely identifies each femto base station and the short identity non-uniquely identifies each femto base station, and

wherein the processing unit is arranged to detect the target FBS based on the short and the long identities of the target FBS.

11. The UE of claim 10, wherein the processing unit is arranged to update the white list in the storage unit to modify information regarding the target FBS to indicate that the UE is not allowed to access the target FBS when the command from the source MBS is to update the white list.

12. The UE of claim 10, wherein the processing unit is arranged to detect and report the target FBS by:

determining whether there are possible femto base stations for the relocation of the UE based on the white list,

identifying a femto base station as the target FBS when it is determined that there are possible femto base stations for the relocation,

determining whether the relocation to the target FBS is allowable after the target FBS is identified, and

reporting the target FBS to the source MBS when it is determined that the relocation to the target FBS is allowable.

13. The UE of claim 12, wherein the processing unit is arranged to determine whether there are possible femto base stations for the relocation of the UE based on at least one of the following conditions being true:

a presence of a base station with a short identity that is listed in the white list as being a femto base station, wherein the short identity non-uniquely identifies a femto base station,

the source MBS is listed in the white list as having a macro cell that over lays one or more femto cell areas,

a timing advance of the source MBS matches one or more timing advances in the white list,

a location of the UE is within a predetermined distance of one or more femto base stations in the white list, and

a current time matches within a predetermined tolerance of one or more normal access times listed for one or more femto base station in the white list.

14. The UE of claim 12, wherein the processing unit is arranged to identify the target FBS and to determine whether the relocation to the target FBS is allowable by:

retrieving the short identity of a detected femto base station,

determining whether the relocation to the detected femto base station is possible based on the short identity,

retrieving the long identity of the detected femto base station when it is determined that the relocation to the detected femto base station is possible based on the short identity,

determining whether the relocation to the detected femto base station is possible based on the long identity, and

reporting the long identity of the detected femto base station as the target FBS to the source MBS when it is determined that the relocation to the detected femto base station is possible based on the long identity.

15. The UE of claim 14, wherein the processing unit is arranged to retrieve the short identity of the detected femto base station and to determine whether the relocation to the detected femto base station based on the short identity is possible by:

requesting the source MBS for a short gap,

receiving a grant of the short gap from the source MBS,

reading the short identity of the detected femto base station during the short gap after receiving the grant of the short gap, and

determining whether the read short identity is in the white list and determining that the relocation is possible when the short identity is in the white list and not possible otherwise,

wherein the short gap is a time slot in which the source MBS will not transmit data to the UE to allow the UE to read the short identity transmitted by the detected femto base station.

16. The UE of claim 15, wherein the processing unit is arranged retrieve the long identity of the detected femto base station and to determine whether the relocation to the detected femto base station based on the short identity is possible by:

requesting the source MBS for a long gap;

receiving a grant of the long gap from the source MBS;

reading the long identity of the detected femto base station during the long gap after receiving grant of the long gap; and

determining whether the read long identity is in the white list and determining that the relocation is possible when the long identity is in the white list and not possible otherwise,

wherein the long gap is a time slot in which the source MBS will not transmit data to the UE to allow the UE to read the long identity transmitted by the femto base station, and

wherein a duration of the long gap is longer than a duration of the short gap.

17. The UE of claim 12, wherein the processing unit is arranged to identify the target FBS and to determine whether the relocation to the target FBS is allowable by:

determining whether the target FBS and the source MBS are on a same carrier,

requesting the source MBS for a long gap when it is determined that the target FBS and the source MBS are on the same carrier,

receiving a grant of the long gap from the source MBS,

reading the long identity of the target FBS during the long gap after receiving the grant of the long gap, and

determining whether the read long identity is in the white list and determining that the relocation is possible when the long identity is in the white list and not possible otherwise,

wherein the long gap is a time slot in which the source MBS will not transmit data to the UE to allow the UE to read the long identity transmitted by the target FBS.

18. The UE of claim 12,

wherein the radio communications unit is arranged to perform as a dual-receiver, and

wherein the processing unit is arranged to identify the target FBS and to determine whether the relocation to the target FBS is allowable by:

reading the long identity transmitted by the femto base station; and

determining whether the read long identity is in the white list and determining that the relocation is possible when the long identity is in the white list and not possible otherwise.

32. The UE of claim 12, wherein the processing unit is arranged to determine whether there are possible femto base stations for relocation in response to a manual triggering operation by a user and/or automatically on a periodic basis.

33. The UE of claim 12, wherein the processing unit is arranged to utilize a short range wireless protocol signal to determine whether there are possible femto base stations for relocation.

34. The UE of claim 18, wherein the radio communications unit is arranged to read the long identity transmitted by the target FBS on a 3GPP radio signal different from a 3GPP radio signal transmitted by the source MBS or transmitted on a short range wireless protocol signal.

19. A method to perform a relocation of a user equipment (UE) from a source macro base station (MBS) to a target femto base station (FBS), comprising:

receiving a request for a short gap from the UE;

granting the short gap to the UE;

receiving a request for a long gap from the UE; and

granting the short gap to the UE;

wherein the short gap is a time slot in which the source MBS will not transmit data to the UE to allow the UE to read a short identity transmitted by the target FBS,

wherein the long gap is a time slot in which the source MBS will not transmit data to the UE to allow the UE to read a long identity transmitted by the target FBS, and

wherein the long identity uniquely identifies the target FBS and the short identity non-uniquely identifies the target FBS,

wherein a duration of the long gap is longer than a duration of the short gap.

20. The method of claim 19, further comprising:

receiving a long identity of the target FBS from the UE;

making a relocation request to a mobility controller of a network to relocate the UE to the target FBS;

receiving a response from the mobility controller;

sending a relocation command to the UE when the response from the mobility controller indicates that the relocation of the UE is allowed; and

sending a white list update command to the UE when the response from the mobility controller indicates that the relocation of the UE is not allowed,

wherein the white list is maintained by the UE and includes information on one or more femto base stations available to provide connectivity to the UE including a short identity and a long identity for each of the one or more femto base stations, and

wherein the long identity uniquely identifies each femto base station and the short identity non-uniquely identifies each femto base station.

21. The method of claim 20, wherein the source MBS is not preconfigured to have knowledge of the target FBS.

22. A macro base station (MBS), comprising:

a radio communications unit arranged to communicate with a user equipment (UE); and

a processing unit arranged to via the radio communications unit;

receive a request for a short gap from the UE;

grant the short gap to the UE;

receive a request for a long gap from the UE;

grant the long gap to the UE;

wherein the short gap is a time slot in which the MBS will not transmit data to the UE to allow the UE to read a short identity transmitted by a target femto base station (FBS),

wherein the long gap is a time slot in which the MBS will not transmit data to the UE to allow the UE to read a long identity transmitted by the target FBS, and

wherein the long identity uniquely identifies the target FBS and the short identity non-uniquely identifies the target FBS,

wherein a duration of the long gap is longer than a duration of the short gap.

23. The MBS of claim 22, further comprising:

a network communications unit arranged to communicate with a mobility controller,

wherein the processing unit is further arranged to;

receive a long identity of the target FBS from the UE via the radio communications unit;

make a relocation request to relocate the UE to the target FBS to the mobility controller of a network via the network communications unit;

receive a response from the mobility controller via the network communications unit;

send a relocation command to the UE via the radio communications unit when the response from the mobility controller indicates that the relocation of the UE is allowed; and

send a white list update command to the UE via the radio communications unit when the response from the mobility controller indicates that the relocation of the UE is not allowed,

wherein the white list is maintained by the UE and includes information on one or more femto base stations available to provide connectivity to the UE including a short identity and a long identity for each of the one or more femto base stations, and

wherein the long identity uniquely identifies each femto base station and the short identity non-uniquely identifies each femto base station.

24. The MBS of claim 23, wherein the MBS is not preconfigured to have knowledge of the target FBS.

25. A method (M1300) to perform a relocation of a user equipment (UE) from a source macro base station (MBS) to a target femto base station (FBS), comprising:

broadcasting a short identity and a long identity of the target FBS;

receiving from a mobility controller a request for relocation of the UE from the source MBS to the target FBS;

determining whether access to the target FBS is allowed based on an identity of the UE;

sending a relocation response to the mobility controller indicating access allowance when it is determined that the UE is allowed to access the target FBS; and

sending the relocation response to the mobility controller indicating access denial when it is determined that the UE is not allowed to access the target FBS, and

wherein the long identity uniquely identifies the target FBS and the short identity non-uniquely identifies the target FBS.

26. The method of claim 25, wherein act of determining whether access to the target FBS is allowed comprises:

comparing the identity of the UE with an access control list, the access control list including identity(ies) of one or more user equipments that is(are) allowed to access the target FBS;

determining that access is allowed when the UE identity is included in the access control list; and

determining that access is not allowed when the UE identity is not included in the access control list.

35. The method of claim 25, wherein in the act of broadcasting the short identity and the long identity of the target FBS, one or both of the short and long identities are broadcasted on a 3GPP radio signal different from a 3GPP radio signal transmitted by the source MBS or on a short range wireless protocol signal.

27. A femto base station (FBS), comprising:

a radio communications unit arranged to communicate with a user equipment (UE);

a network communications unit arranged to communicate with a mobility controller of a network;

a processing unit arranged to;

broadcast a short identity and a long identity of the FBS via the radio communications unit;

receive from a mobility controller via the network communications unit a request for relocation of the UE from a source macro base station (MBS);

determine whether access to the FBS is allowed based on an identity of the UE;

send a relocation response to the mobility controller via the network communications unit indicating access allowance when it is determined that the UE is allowed to access the target FBS; and

send the relocation response to the mobility controller via the network communications unit indicating access denial when it is determined that the UE is not allowed to access the target FBS, and

wherein the long identity uniquely identifies the FBS and the short identity non-uniquely identifies the FBS.

28. The FBS of claim 27, further comprising:

a storage unit arranged to store an access control list, the access control list including identity(ies) of one or more user equipments that is(are) allowed to access the FBS,

wherein the processing unit is arranged to determine whether the access to the FBS is allowed by;

comparing the identity of the UE with the access control list,

determining that access is allowed when the UE identity is included in the access control list; and

determining that access is not allowed when the UE identity is not included in the access control list.

36. The FBS of claim 27, wherein in the processing unit is arranged to broadcast the short identity and/or the long identity on a 3GPP radio signal different from a 3GPP radio signal transmitted by the source MBS or on a short range wireless protocol signal.

37. A method to perform a relocation of a user equipment (UE) from a source macro base station (MBS) to a target femto base station (FBS), comprising:

receiving a request for relocation from a source mobility controller or from the source MBS;

determining whether access is allowed locally within a mobility controller or allowing the target FBS to determine whether the access is allowed;

sending an access allowed response to the source mobility controller or to the source MBS when it is determined that the access is allowed; and

sending an access denied response to the source mobility controller or to the source MBS when it is determined that the access is not allowed,

wherein when the access is determined locally within the mobility controller, the method further comprises;

notifying the target FBS 120 of the relocation request and a grant of the request; and

receiving an acknowledgment from the target FBS 120, and

wherein when the target FBS is allowed to determine access, the method further comprises;

forwarding the relocation request to the target FBS; and

receiving one of the access allowed response or the access denied response from the target FBS.

38. A mobility controller, comprising:

a network communications unit arranged to communicate with another mobility controller, a source macro base station (MBS), and a target femto base station (FBS); and

a processing unit arranged to;

receive a request for relocation from the another mobility controller or from the source MBS,

locally determine whether access is allowed or allow the target FBS to determine whether the access is allowed,

send an access allowed response to the another mobility controller or to the source MBS when it is determined that the access is allowed, and

send an access denied response to the another mobility controller or to the source MBS when it is determined that the access is not allowed,

wherein when the processor unit locally determines the access, the processor unit is arranged to;

notify the target FBS 120 of the relocation request and a grant of the request, and

receive an acknowledgment from the target FBS 120, and

wherein when the target FBS is allowed to determine access, the processor unit is arranged to;

forward the relocation request to the target FBS; and

receive one of the access allowed response or the access denied response from the target FBS.

39. The mobility controller of claim 38, further comprising:

a storage unit arranged to store an access control list, the access control list including identity(ies) of one or more user equipments that is(are) allowed to access the target FBS,

wherein the processing unit is arranged to determine whether the access to the target FBS is allowed by;

comparing the identity of the UE with the access control list,

determining that access is allowed when the UE identity is included in the access control list; and

determining that access is not allowed when the UE identity is not included in the access control list.