Method for establishing a signaling connection with a mobile station

• US 6,792,278 B1
• Filed: 11/07/2000
• Issued: 09/14/2004
• Est. Priority Date: 04/03/1998
• Status: Expired due to Term

• Current Assignee: Conversant Wireless Licensing S.à.r.l. (f/k/a Core Wireless Licensing S.a.r.l.) (MOSAID Technologies Inc. (f/k/a Conversant Intellectual Property Management))
• Original Assignee: Nokia Networks (Nokia Corporation)
• Inventors: Vialen, Jukka, Ahmavaara, Kalle
• Primary Examiner(s): Trost, William
• Assistant Examiner(s): RAMPURIA, SHARAD K
• Application Number:
  US09/647,022
• Time in Patent Office: 1,407 Days
• Field of Search: 455/461, 455/458, 455/432.1, 455/433, 455/435.1, 455/445, 455/567, 455/551, 455/552.1, 370/310, 370/312, 370/230, 370/328-329
• US Class Current: 455/461
• CPC Class Codes: H04W 68/00 User notification, e.g. alerting and paging, for incoming communication, change of service or the like

Abstract

The invention comprises a method for establishing a signaling connection with a mobile station, which method is particularly applicable to third-generation mobile communications networks. A database is created at a node of a mobile communications network, and a mobile station connected with the network sends to said database information about all its subscriber identities (403). In the database, information is added (404) to the subscriber identity information which may be useful when said mobile station is paged (410, 411). Such contactability information includes e.g. the mobile station'"'"'s location information, information about existing signaling connections and information about the primary paging channel monitored by the mobile station. The contactability information is updated according to changes detected in the status of the mobile station (406). The database will be discontinued for a mobile station that has had no connections for a predetermined time. The method reduces paging channel load in cells, reduces the need of mobile stations to listen to paging channels and makes radio access networks connections to multiple core networks more practical.

Claims

1. A method for establishing a signaling connection with an active mobile station assigned at least two subscriber identities, wherein the method comprises the steps of:

creating a paging database of mobile stations with active connections in a radio access network (RAN) of a radio network controller (RNC) that includes said paging database, wherein said paging database comprises subscriber identities and contactability information for the corresponding active mobile stations, wherein said at least two subscriber identities of said mobile station comprise a first subscriber identity under which said mobile station has a present active connection in said RAN; and

if a new signaling connection under a second subscriber identity is to be established with said mobile station, the RNC uses said subscriber identity and contactability information in said paging database to establish the new signaling connection under the second subscriber identity by only signaling a base transceiver station (BTS) having the present active connection under the first subscriber identity with said mobile station.

2. The method of claim 1, wherein the paging database is located in a core network (CN).

3. The method of claim 1, wherein said contactability information comprises location information concerning said active mobile stations.

4. The method of claim 1, wherein said contactability information comprises information about signaling connections associated with data connections of said active mobile stations.

5. The method of claim 1, wherein said contactability information comprises information about primary paging channels monitored by said active mobile stations.

6. The method of claim 1, wherein a call for said mobile station, associated with said second subscriber identity, arrives in a node of a core network connected with said RAN, and wherein the signaling required by said received call uses the same signaling connection as is being used in the signaling of the present active connection.

7. The method of claim 5, wherein said mobile station has a main subscriber identity (IMSI_m) which is stored in the paging database, further comprising the steps of:

ceasing said present active connection under said first subscriber identity, thereby putting said mobile station in standby model;

receiving a call for said mobile station in a node of a core network connected with said RAN; and

sending a paging message corresponding to said call to a paging channel according to the paging database contactability information associated with the main subscriber identity IMSI_m.

8. The method of claim 3, further comprising the steps of:

ceasing said present active connection under said first subscriber identity, thereby putting said mobile station in standby mode;

receiving a call for said mobile station, associated with said second subscriber identity, in a node of a core network connected with said RAN; and

sending a paging message corresponding to said call from the RNC of said RAN to a cell corresponding to the location information in the paging database contactability information associated with said first subscriber identity.

9. The method of claim 1, further comprising the step of:

sending, by said mobile station, to the RNC information about all subscriber identities used by it in order for the RNC to collect said subscriber identity information in the paging database.

10. The method of claim 9, wherein the sending step comprises the step of:

sending said subscriber identity information in a MAC-layer message on a channel intended for MAC-layer messages.

11. The method of claim 10, wherein said signaling channel intended for MAC-layer messages is the RACH.

12. The method of claim 9, wherein the sending step comprises the step of:

sending said subscriber identity information in an RRC-layer message on a channel intended for RRC-layer messages.

13. The method of claim 12, wherein said signaling channel intended for RRC-layer messages belongs to the SRB channels.

14. The method of claim 12, wherein said RRC-layer message is a message defined specifically for the transfer of subscriber identity information.

15. The method of claim 12, further comprising the steps of:

receiving, by said mobile station during the establishment of a data connection, a paging message; and

sending, by said mobile station, a response message for the paging message, wherein said subscriber identity information is included in said response message for the paging message.

16. The method of claim 12, wherein said subscriber identity information is included in a message indicating parameter values for the mobile station.

17. The method of claim 1, further comprising the step of:

updating the contactability information associated with said mobile station when said mobile station moves from one cell to another.

18. The method of claim 1, wherein said present active connection under said first subscriber identity has ceased, thereby putting said mobile station in standby mode, further comprising the step of:

updating the contactability information associated with said mobile station when said mobile station moves from one location area (LA) to another location area.

19. The method of claim 1, wherein the mobile station comprises a mobile telephone.

20. The method of claim 1, wherein said subscriber identities are international mobile subscriber identities (IMSI) in a GSM or UMTS system.

21. The method of claim 1, wherein said first subscriber identity of the at least two subscriber identities is used by a first core network (CN₁) and said second subscriber identity of the at least two subscriber identities is used by a second core network (CN₂), and wherein said method of claim 1 allows the mobile station to receive data connections from both CN₁ and CN₂.

39. The method of claim 1, further comprising the step of:

updating said contactability information when contactability changes are detected.

54. The method of claim 6, wherein the mobile station with the present active connection under the first subscriber identity does not actively listen on a paging channel because any signaling required by a new call would use the same signaling connection as the present active connection.

65. The method of claim 5, wherein the present active connection under said first subscriber identity with said mobile station has ceased, further comprising the step of:

sending a paging message to said mobile station on at least one primary paging channel, wherein the at least one primary paging channel is specified in said contactability information, thereby allowing said mobile station to listen to only said at least one primary paging channel.

22. A telecommunication system for establishing a signaling connection with a mobile station assigned at least two subscriber identities, comprising:

a radio network controller (RNC) having a radio access network (RAN); and

a paging database in communication with said RNC comprising subscriber identities and contactability information of active mobile stations in the RAN of said RNC, said active mobile stations including the mobile station assigned said at least two subscriber identities, wherein said paging database comprises said at least two subscriber identities of said mobile station;

wherein said RNC comprises;

means for establishing, if there is a present active connection under a first subscriber identity of said at least two subscriber identities with said mobile station, a new signaling connection under a second subscriber identity of the at least two subscriber identities with the mobile station using subscriber identity and contactability information in said paging database by only signaling a base transceiver station (BTS) having the present active connection under said first subscriber identity with said mobile station.

40. The telecommunication system of claim 22, further comprising:

means for updating said contactability information in said paging database when contactability changes are detected.

49. The telecommunications system of claim 22, wherein the act of only signaling the BTS having the present active connection under said first subscriber identity is performed using said present active connection.

55. The telecommunication system of claim 22, wherein there is a present active connection under said first subscriber identity with said mobile station, and wherein, if a new signaling connection under said second subscriber identity is being established, any initial signaling required with said mobile station by said new signaling connection would use the same signaling connection as the present active connection.

56. The telecommunication system of claim 55, wherein the mobile station with the present active connection under said first subscriber identity does not actively listen on a paging channel because any initial signaling required by a new signaling connection would use the same signaling connection as the present active connection.

66. The telecommunication system of claim 22, wherein said contactability information comprises at least one specified paging channel for said mobile station, and wherein, if there is no active data connection with said mobile station, said RNC transmits a paging message on said at least one specified paging channel, thereby allowing said mobile station to listen to only said at least one specified paging channel for paging messages.

23. A mobile station in a mobile telecommunication system, said mobile station having at least two subscriber identities, comprising:

means for transmitting at least one of contactability information and the at least two subscriber identities to a radio network controller (RNC) in whose radio access network (RAN) the mobile station is presently located;

wherein a paging database in said RNC receives and stores the transmitted contactability information and at least two subscriber identities; and

wherein, if said mobile station has an active data connection under a first subscriber identity of the at least two subscriber identities, the at least one of the at least two subscriber identities and contactability information stored in the paging database are used by said RNC to establish a new signaling connection under a second subscriber identity of the at least two subscriber identities with the mobile station by only signaling a base transceiver station (BTS) having the active data connection under said first subscriber identity with said mobile station.

24. The mobile station of claim 23, wherein at least one of the contactability information and the at least two subscriber identities are transmitted when the mobile station established a data connection under a first subscriber identity of the at least two subscriber identities.

41. The mobile station of claim 23, wherein said contactability information in said paging database is updated when contactability changes are detected.

42. The mobile station of claim 23, wherein the at least one of contactability information and the at least two subscriber identities are transmitted when the mobile station first enters the RAN of the RNC.

43. The mobile station of claim 23, wherein the at least one of contactability information and the at least two subscriber identities are transmitted when the mobile station first becomes active in the RAN of the RNC.

44. The mobile station of claim 23, wherein the at least one of contactability information and the at least two subscriber identities are transmitted when the RNC establishes a data connection with the mobile station.

50. The mobile station of claim 23, wherein the act of only signaling the BTS having the active data connection under said first subscriber identity is performed using said active data connection.

57. The mobile station of claim 23, wherein the mobile station has an active data connection under said first subscriber identity, and wherein, if a new signaling connection under said second subscriber identity is being established, any initial signaling required with said mobile station by said new signaling connection would use the same signaling connection as the active data connection.

58. The mobile station of claim 57, wherein the mobile station does not actively listen on a paging channel because any initial signaling required by a new signaling connection would use the same signaling connection as the present active connection.

67. The mobile station of claim 23, wherein said contactability information comprises at least one specified paging channel for the mobile station, and wherein, if there is no active data connection with said mobile station, said RNC transmits a paging message on said at least one specified paging channel, thereby allowing said mobile station to listen to only said at least one specified paging channel for paging messages.

25. A paging database in a radio network controller (RNC) of a telecommunication system, said paging database for assisting in the establishment of signaling connections with mobile stations, comprising:

means for receiving contactability information and at least two subscriber identities corresponding to a mobile station located in a radio access network (RAN) of the RNC;

means for storing said contactability information and a plurality of subscriber identities corresponding to the mobile station located in the RAN of the RNC; and

means for retrieving said contactability information and the at least two subscriber identities corresponding to the mobile station when a call under a second subscriber identity of the at least two subscriber identities is received, said retrieval performed by searching for said second subscriber identity of the at least two subscriber identities;

wherein, if there is a present active connection under a first subscriber identity of said at least two subscriber identities with said mobile station, the RNC uses the retrieved contactability information and the at least two subscriber identities corresponding to the active mobile station to establish a new signaling connection with the mobile station for the received call under the second subscriber identity by only signaling a base transceiver station (BTS) having the present active connection under said first subscriber identity with the mobile station.

26. The paging database of claim 25, wherein the contactability information and the at least two subscriber identities are received when the mobile station established a data connection under a first subscriber identity of the at least two subscriber identities.

27. The paging database of claim 25, further comprising:

means for eliminating stored contactability information and the at least two subscriber identities corresponding to the mobile station when no data traffic is transmitted to or from the mobile station for a predetermined period of time.

45. The paging database of claim 25, further comprising:

means for updating said contactability information in said paging database when contactability changes are detected.

46. The paging database of claim 25, wherein said means for storing said contactability information and plural subscriber identities corresponding to active mobile station located in the RAN of the RNC retain contactability information and subscriber identities of mobile terminal which no longer have active connections.

51. The paging database of claim 25, wherein the act of only signaling the BTS having the present active connection under said first subscriber identity is performed using said present active connection.

59. The paging database of claim 25, wherein there is a present active connection under said first subscriber identity with said mobile station, and wherein, if a call under said second subscriber identity is being established, any initial signaling required by said call would use the same signaling connection as the present active connection.

60. The paging database system of claim 59, wherein the mobile station with the present active connection under said first subscriber identity does not actively listen on a paging channel because any initial signaling required by a new signaling connection would use the same signaling connection as the present active connection.

68. The paging database of claim 25, wherein said contactability information comprises at least one specified paging channel for the mobile station, and wherein, if there is no present active connection with said mobile station, said RNC transmits a paging message on said at least one specified paging channel, thereby allowing said mobile station to listen to only said at least one specified paging channel for paging messages.

28. A radio access network (RAN) for establishing a data connection with a mobile station in a traffic area of said RAN, wherein said mobile station has been assigned a first subscriber identity and a second subscriber identity, comprising:

a radio network controller (RNC) for receiving a paging request based on a received call to the second subscriber identity, and for retrieving a record corresponding to the second subscriber identity from a paging database, wherein said record comprises the first and second subscriber identities and contactability information of the mobile station, and wherein said record was previously created when the mobile station transmitted the first and second subscriber identities to the RNC;

wherein, if there is an existing data connection under the first subscriber identity with the mobile station, said RNC only signals a base transceiver station (BTS) with the existing data connection under the first subscriber identity with the mobile station and establishes a new data connection under the second subscriber identity with the mobile station for the received call, wherein said BTS is known from the retrieved record.

29. The RAN of claim 28, wherein said contactability information comprises at least one of information about a cell in which the mobile station is located, information about the signaling connections of the mobile station'"'"'s existing data connections, and information about a primary paging channel monitored by the mobile station.

30. The RAN of claim 28, wherein the first subscriber identity is a first international mobile subscriber identity (IMSI₁) and the second subscriber identity is a second international mobile subscriber identity (IMSI₂) in a GSM or UMTS system.

52. The RAN of claim 28, wherein the act of only signaling the BTS with the existing data connection under the first subscriber identity is performed using said existing data connection.

61. The RAN of claim 28, wherein there is an existing data connection under said first subscriber identity with said mobile station, and wherein, if a new data connection under said second subscriber identity is being established, any initial signaling required by said new data connection would use the same signaling connection as the existing data connection.

62. The RAN of claim 61, wherein the mobile station with the existing data connection under said first subscriber identity does not actively listen on a paging channel because any signaling required by a new data connection would use the same signaling connection as the existing data connection.

69. The RAN of claim 28, wherein said contactability information comprises at least one specified paging channel for the mobile station, and wherein, if there is no existing data connection with said mobile station, said RNC transmits a paging message on said at least one specified paging channel, thereby allowing said mobile station to listen to only said at least one specified paging channel for paging messages.

31. A method for establishing a data connection in a mobile telecommunications system, comprising the steps of:

transmitting, by a mobile station having a first subscriber identity and a second subscriber identity, said first and second subscriber identities to a radio network controller (RNC) of a radio access network (RAN) in which said mobile station is located;

receiving, by a paging database located in the RNC, said first and second subscriber identities and storing a record comprising said first and second subscriber identities with contactability information about the mobile station;

receiving a call under the second subscriber identity; and

searching, by the RNC, the paging database by the second subscriber identity, finding, and then retrieving said record;

wherein, if there is an existing data connection under the first subscriber identity with the mobile station, the RNC only signals a base transceiver station (BTS) having the existing data connection under the first subscriber identity with the mobile station in order to establish a new data connection under the second subscriber identity with the mobile station for the received call, wherein said BTS is known from the retrieved record.

32. The method of claim 31, wherein a first core network (CN₁) assigned the first subscriber identity to the mobile station and a second core network (CN₂) assigned the second subscriber identity to the mobile station.

33. The method of claim 31, wherein a mobile switching center (MSC) or a serving GPRS support node (SGSN) receives the call under the second subscriber identity, further comprising the step of:

sending, by the MSC or the SGSN, a paging request to the RNC.

34. The method of claim 31, wherein the step of transmitting the first and second subscriber identities is performed at least one of when establishing a data connection with the mobile station or when the mobile station first becomes active.

35. The method of claim 31, wherein the step of transmitting the first and second subscriber identities is performed when establishing a data connection under the first subscriber identity.

36. The method of claim 31, further comprising the step of:

if there is no existing data connection with the mobile station, beginning paging based on the contactability information in the retrieved record.

37. The method of claim 31, wherein said contactability information comprises at least one of information about a cell in which the mobile station is located, information about the signaling connections of the mobile station'"'"'s existing data connections, and information about a primary paging channel monitored by the mobile station.

38. The method of claim 37, further comprising the step of:

if there is no existing data connection with the mobile station, checking the contactability information in the retrieved record to determine whether the mobile station is in a same location area as where it was when a previous data connection was terminated.

47. The method of claim 31, wherein the contactability information concerns the ability of the mobile telecommunications system to contact the subscriber associated with said mobile station.

48. The method of claim 31, wherein the contactability information comprises at least location information about the mobile station.

53. The method of claim 31, wherein said only signaling the BTS having the existing data connection under the first subscriber identity is performed using the existing data connection.

63. The method of claim 31, wherein there is an existing data connection under said first subscriber identity with said mobile station, and wherein, if a new data connection under said second subscriber identity is being established, any initial signaling required by said new data connection would use the same signaling connection as the existing data connection.

64. The method of claim 63, wherein the mobile station with the existing data connection under said first subscriber identity does not actively listen on a paging channel because any signaling required by a new data connection would use the same signaling connection as the existing data connection.

70. The method of claim 31, wherein said contactability information comprises at least one specified paging channel for the mobile station, and wherein, if there is no existing data connection with said mobile station, said RNC transmits a paging message on said at least one specified paging channel, thereby allowing said mobile station to listen to only said at least one specified paging channel for paging messages.