METHOD AND APPARATUS FOR MAINTAINING LOCATION CONTINUITY FOR A UE FOLLOWING HANDOVER

• US 20100202407A1
• Filed: 02/08/2010
• Published: 08/12/2010
• Est. Priority Date: 02/09/2009
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Edge, Stephen W.
• Granted Patent: US 9,307,454 B2
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04W 36/0005 Control or signalling for completing the hand-off
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 36/385 of the core network
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 76/50 for emergency connections

Abstract

Techniques for maintaining location continuity for a user equipment (UE) following handover are described. The UE communicates with a first radio access network (RAN) and is served by a source serving node and a source location server prior to handover. The UE communicates with a second RAN and is served by a target serving node and a target location server after the handover. In an aspect, location continuity may be maintained for the UE by transferring an identity of the target serving node to a location server during handover of the UE. In one design, the target serving node sends its identity to the target location server, which updates a Location and Routing Function (LRF) serving the UE. In another design, for handover from packet-switched domain to circuit-switched domain, the source serving node sends the target serving node identity to the source location server, which updates the LRF.

Claims

1. A method of supporting location services, comprising:

receiving an indication of handover of a user equipment (UE) from a first radio access network (RAN) to a second RAN, wherein the UE is served by a source serving node via the first RAN prior to the handover and is served by a target serving node via the second RAN after the handover; and

sending an identity of the target serving node to a location server to support location services for the UE via the second RAN after the handover.

2. The method of claim 1, wherein the UE has an emergency call when the handover occurs.

3. The method of claim 1, wherein the receiving the indication of handover and the sending the identity of the target serving node are performed by the target serving node.

4. The method of claim 3, wherein the location server is a target location server supporting location services for the UE after the handover.

5. The method of claim 1, wherein the first RAN supports packet-switched calls and the second RAN supports circuit-switched calls, and wherein the receiving the indication of handover and the sending the identity of the target serving node are performed by the source serving node.

6. The method of claim 5, wherein the location server is a source location server supporting location services for the UE prior to the handover.

7. The method of claim 1, wherein the target serving node comprises a Mobility Management Entity (MME), or a Serving GPRS Support Node (SGSN), or a Mobile Switching Center (MSC), or a MSC server.

8. The method of claim 1, wherein the location server comprises a Gateway Mobile Location Center (GMLC), or a Mobile Positioning Center (MPC), or a Location and Routing Function (LRF).

9. The method of claim 1, wherein the first and second RANs support packet-switched calls, or the first RAN supports packet-switched calls and the second RAN supports circuit-switched calls.

10. The method of claim 1, wherein the first RAN supports a first radio access technology (RAT), and wherein the second RAN supports a second RAT different from the first RAT.

11. An apparatus for supporting location services, comprising:

means for receiving an indication of handover of a user equipment (UE) from a first radio access network (RAN) to a second RAN, wherein the UE is served by a source serving node via the first RAN prior to the handover and is served by a target serving node via the second RAN after the handover; and

means for sending an identity of the target serving node to a location server to support location services for the UE via the second RAN after the handover.

12. The apparatus of claim 11, wherein the means for receiving the indication of handover and the means for sending the identity of the target serving node are for the target serving node.

13. The apparatus of claim 12, wherein the location server is a target location server supporting location services for the UE after the handover.

14. An apparatus for supporting location services, comprising:

at least one processor configured to receive an indication of handover of a user equipment (UE) from a first radio access network (RAN) to a second RAN, wherein the UE is served by a source serving node via the first RAN prior to the handover and is served by a target serving node via the second RAN after the handover, and to send an identity of the target serving node to a location server to support location services for the UE via the second RAN after the handover.

15. The apparatus of claim 14, wherein the apparatus is for the target serving node.

16. The apparatus of claim 15, wherein the location server is a target location server supporting location services for the UE after the handover.

17. A computer program product, comprising:

a computer-readable medium comprising;

code to cause at least one computer to receive an indication of handover of a user equipment (UE) from a first radio access network (RAN) to a second RAN, wherein the UE is served by a source serving node via the first RAN prior to the handover and is served by a target serving node via the second RAN after the handover, and

code to cause the at least one computer to send an identity of the target serving node to a location server to support location services for the UE via the second RAN after the handover.

18. A method of supporting location services, comprising:

receiving an identity of a target serving node for a user equipment (UE) at a location server, wherein the UE performs handover from a first radio access network (RAN) to a second RAN, and wherein the UE is served by a source serving node via the first RAN prior to the handover and is served by the target serving node via the second RAN after the handover; and

supporting location services for the UE before the handover, or after the handover, or both by the location server.

19. The method of claim 18, wherein the UE has an emergency call when the handover occurs.

20. The method of claim 18, wherein the location server is a target location server supporting location services for the UE after the handover.

21. The method of claim 20, wherein the identity of the target serving node is received from the target serving node.

22. The method of claim 18, wherein the first RAN supports packet-switched calls and the second RAN supports circuit-switched calls, and wherein the location server is a source location server supporting location services for the UE before the handover.

23. The method of claim 22, wherein the identity of the target serving node is received from the source serving node.

24. The method of claim 18, further comprising:

updating a Location and Routing Function (LRF) with the identity of the target serving node by the location server.

25. An apparatus for supporting location services, comprising:

means for receiving an identity of a target serving node for a user equipment (UE) at a location server, wherein the UE performs handover from a first radio access network (RAN) to a second RAN, and wherein the UE is served by a source serving node via the first RAN prior to the handover and is served by the target serving node via the second RAN after the handover; and

means for supporting location services for the UE before the handover, or after the handover, or both by the location server.

26. The apparatus of claim 25, wherein the location server is a target location server supporting location services for the UE after the handover, and wherein the identity of the target serving node is received from the target serving node.

27. The apparatus of claim 25, further comprising:

means for updating a Location and Routing Function (LRF) with the identity of the target serving node by the location server.

28. A method of supporting location services, comprising:

receiving an identity of a target serving node for a user equipment (UE) at a Location and Routing Function (LRF), wherein the UE performs handover from a first radio access network (RAN) to a second RAN, and wherein the UE is served by a source serving node via the first RAN prior to the handover and is served by the target serving node via the second RAN after the handover; and

determining a target location server to support location services for the UE after the handover.

29. The method of claim 28, wherein the LRF supports an emergency call for the UE before and after the handover.

30. The method of claim 28, wherein the identity of the target serving node is received from the target location server.

31. The method of claim 28, wherein the first RAN supports packet-switched calls and the second RAN supports circuit-switched calls, and wherein the identity of the target serving node is received from a source location server supporting location services for the UE prior to the handover.

32. The method of claim 31, further comprising:

receiving an identity of the UE from the source location server; and

transferring the identity of the UE from the LRF to the target location server.

33. The method of claim 28, further comprising:

replacing a source location server with the target location server if the source location server is different from the target location server.

34. The method of claim 28, further comprising:

initiating a location session for the UE based on the identity of the target serving node.

35. An apparatus for supporting location services, comprising:

means for receiving an identity of a target serving node for a user equipment (UE) at a Location and Routing Function (LRF), wherein the UE performs handover from a first radio access network (RAN) to a second RAN, and wherein the UE is served by a source serving node via the first RAN prior to the handover and is served by the target serving node via the second RAN after the handover; and

means for determining a target location server to support location services for the UE after the handover.

36. The apparatus of claim 35, wherein the identity of the target serving node is received from the target location server.

37. The apparatus of claim 35, further comprising:

means for receiving an identity of the UE from the source location server; and

means for transferring the identity of the UE from the LRF to the target location server.

38. The apparatus of claim 35, further comprising:

means for initiating a location session for the UE based on the identity of the target serving node.

39. A method of obtaining location services, comprising:

performing handover by a user equipment (UE) from a first radio access network (RAN) to a second RAN, wherein the UE is served by a source serving node via the first RAN prior to the handover and is served by a target serving node via the second RAN after the handover, and wherein an identity of the target serving node is sent to a location server to support location services for the UE after the handover;

obtaining location services by the UE via the first RAN before the handover; and

obtaining location services by the UE via the second RAN after the handover.

40. The method of claim 39, further comprising:

communicating with the first RAN prior to the handover and with the second RAN after the handover for an emergency call.

41. The method of claim 39, wherein the obtaining location services by the UE via the second RAN after the handover comprises

exchanging messages for a location session initiated after the handover based on the identity of the target serving node.

42. The method of claim 39, wherein the UE obtains location services via a user plane location solution prior to the handover and via a control plane location solution after the handover.

43. The method of claim 39, wherein the UE obtains location services via a control plane location solution prior to the handover and via a user plane location solution after the handover.

44. An apparatus for obtaining location services, comprising:

means for performing handover by a user equipment (UE) from a first radio access network (RAN) to a second RAN, wherein the UE is served by a source serving node via the first RAN prior to the handover and is served by a target serving node via the second RAN after the handover, and wherein an identity of the target serving node is sent to a location server to support location services for the UE after the handover;

means for obtaining location services by the UE via the first RAN before the handover; and

means for obtaining location services by the UE via the second RAN after the handover.

45. The apparatus of claim 44, wherein the means for obtaining location services by the UE via the second RAN after the handover comprises

means for exchanging messages for a location session initiated after the handover based on the identity of the target serving node.

46. An apparatus for obtaining location services, comprising:

at least one processor configured to perform handover by a user equipment (UE) from a first radio access network (RAN) to a second RAN, wherein the UE is served by a source serving node via the first RAN prior to the handover and is served by a target serving node via the second RAN after the handover, and wherein an identity of the target serving node is sent to a location server to support location services for the UE after the handover;

to obtain location services by the UE via the first RAN before the handover; and

to obtain location services by the UE via the second RAN after the handover.

47. The apparatus of claim 46, wherein the at least one processor is further configured to exchange messages for a location session initiated after the handover based on the identity of the target serving node.

48. A computer program product, comprising:

a computer-readable medium comprising;

code to cause at least one computer to perform handover by a user equipment (UE) from a first radio access network (RAN) to a second RAN, wherein the UE is served by a source serving node via the first RAN prior to the handover and is served by a target serving node via the second RAN after the handover, and wherein an identity of the target serving node is sent to a location server to support location services for the UE after the handover;

code to cause the at least one computer to obtain location services by the UE via the first RAN before the handover; and

code to cause the at least one computer to obtain location services by the UE via the second RAN after the handover.