Forced registration in concurrent services mobile station handoff

• US 20040203780A1
• Filed: 07/31/2002
• Published: 10/14/2004
• Est. Priority Date: 07/31/2002
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Julka, Vibhor, Gustavsson, Roger
• Granted Patent: US 7,623,865 B2
• Time in Patent Office: Days
• US Class Current: 455/436
• CPC Class Codes: H04W 36/0064 of control information between different access points

Abstract

A wireless communication network, such as a 1xEV-DV network, manages concurrent services handoff to force re-registration of concurrent-services capable mobile stations that have undergone hard handoff during an active voice call. During such handoffs, the mobile station moves from a source base station to a target base station, each supporting concurrent services, and with each base station having associated network identification parameters. In response to receiving the mobile station in hard handoff while it is engaged in an active voice call, the target base station sends one or more of these network identification parameters as dummy values, which results in re-registration of the mobile station on the voice side of the network. The target base station broadcasts actual network identification parameters on one or more overhead channels such that the mobile stations operating in its coverage area have access to true network identification parameters.

Claims

1. In a wireless communication network supporting concurrent voice and data services, wherein a mobile station undergoes a hard handoff from a source base station to a target base station while engaged in an active voice call, a method of performing the hard handoff comprising:

receiving the mobile station in a hard handoff from the source base station at the target base station; and

transmitting one or more dummy network identification parameters from the target base station to the mobile station while the voice call is active.

2. The method of claim 1, wherein transmitting one or more dummy network identification parameters comprises transmitting a dummy value for at least one of a System Identification (SID) value, a Network Identification (NID) value, and a Packet Zone Identification (PZID) value.

3. The method of claim 2, wherein transmitting a dummy value for at least one of a System Identification (SID) value, a Network Identification (NID) value, and a Packet Zone Identification (PZID) value comprises transmitting actual NID and SID values in conjunction with a dummy PZID value.

4. The method of claim 3, further comprising receiving origination messages from the mobile station at the network.

5. The method of claim 4, wherein receiving origination messages from the mobile station at the network comprises receiving, at the target base station, an enhanced origination message (EOM) that includes a prior PZID value associated with the source base station.

6. The method of claim 5, further comprising:

generating a packet data registration message including the prior PZID value received from the mobile station; and

sending the packet data registration message to a Packet Data Serving Node (PDSN) supporting packet data routing for the target base station.

7. The method of claim 4, wherein receiving origination messages from the mobile station at the network comprises receiving, at the target base station, an origination message (OM) that includes a dummy PZID value associated with the target base station.

8. The method of claim 7, further comprising:

suppressing generation of a packet data registration message at the target base station responsive to recognizing the dummy PZID value received in the OM; and

triggering re-registration of the mobile station with a home location register (HLR) associated with the mobile station responsive to receiving the OM from the mobile station.

9. The method of claim 4, wherein receiving origination messages from the mobile station at the network comprises receiving, at the target base station, an enhanced origination message (EOM) that includes a prior PZID value associated with the source base station.

10. The method of claim 9, further comprising initiating packet data re-registration of the mobile station responsive to receiving the EOM.

11. The method of claim 10, further comprising:

determining whether the prior PZID value is a true or false PZID value; and

including the prior PZID value in a packet data registration message used to initiate packet data re-registration of the mobile station responsive to receiving the EOM.

12. The method of claim 11, further comprising:

deriving a true PZID value from the prior PZID value if the prior PZID value is a false PZID value; and

including the prior PZID value in a packet data registration message used to initiate packet data re-registration of the mobile station responsive to receiving the EOM.

13. The method of claim 1, wherein transmitting one or more dummy network identification parameters from the target base station to the mobile station while the voice call is active comprises sending one or more dummy network identifiers associated with mobility management for circuit-switched call service.

14. The method of claim 1, wherein transmitting one or more dummy network identification parameters from the target base station to the mobile station while the voice call is active comprises sending one or more dummy network identifiers associated with mobility management for packet-switched call service.

15. The method of claim 1, wherein sending the dummy network identification information comprises sending one or more dummy network identification values as part of an in-system traffic message sent to the mobile station by the target base station on a communication channel associated with the active voice call.

16. The method of claim 15, wherein the wireless communication network comprises a 1×

EV-DV network, and the in-system traffic message comprises an In System Traffic Parameters (ISTP) message.

17. The method of claim 1, further comprising:

receiving the one or more dummy network identification parameters at the mobile station from the target base station while the mobile station is engaged in the active voice call; and

storing the one or more dummy network identification parameters at the mobile station.

18. The method of claim 17, further comprising monitoring a common channel transmitted by the target base station at the mobile station to obtain actual network identification parameters.

19. The method of claim 18, further comprising:

comparing the one or more dummy network identification parameters to the actual network identification parameters; and

initiating re-registration of the mobile station with the wireless communication network upon recognizing a mismatch between the dummy and actual network identification parameters.

20. The method of claim 19, further comprising updating home location register (HLR) routing information for the mobile station responsive to the mobile station re-registering with the wireless communication network.

21. The method of claim 1, wherein transmitting one or more dummy network identification parameters from the target base station to the mobile station while the voice call is active comprises transmitting the one or more dummy network identification parameters only if the hard handoff is an inter-MSC handoff.

22. The method of claim 21, wherein the target base station determines whether the hard handoff is an inter-MSC handoff.

23. The method of claim 21, wherein a target mobile switching center (MSC) associated with the target base station determines whether the hard handoff is an inter-MSC handoff.

24. A base station supporting concurrent circuit-switched and packet-switched services for use in a wireless communication network, the base station operative to:

receive a given mobile station in a hard handoff while the mobile station is engaged in an active voice call; and

transmit a first message including one or more dummy network identification parameters to the mobile station during the active voice call to force re-registration of the mobile station after the active voice call ends.

25. The base station of claim 24, wherein the base station transmits true network identification parameters on a broadcast channel for use by mobile stations operating in a coverage area of the base station.

26. The base station of claim 24, wherein the base station transmits the first message responsive to an indication from a mobile switching center that the handoff to the base station is a hard handoff.

27. The base station of claim 24, wherein the base station receives the one or more dummy parameters from the mobile switching center for transmission to the mobile station.

28. The base station of claim 24, wherein the base station is further operative to determine that the handoff of the mobile station is a hard handoff and thereby transmit the first message responsive to such recognition.

29. The base station of claim 24, wherein the base station is further operative to receive an indication from a supporting mobile switching center that the handoff is a hard handoff, and thereby transmit the first message responsive to such indication.

30. The base station of claim 24, wherein the base station is further operative to:

receive an origination message that includes a Packet Zone Identifier (PZID) from the mobile station; and

suppress packet-switched re-registration of the mobile station if the PZID matches a dummy PZID associated with the base station.

31. The base station of claim 30, wherein the base station is further operative to initiate circuit-switched re-registration of the mobile station if the PZID matches the dummy PZID associated with the base station.

32. The base station of claim 30, wherein the base station is further operative to initiate packet-data re-registration of the mobile station if the PZID is a dummy PZID that does not match the dummy PZID associated with the base station.

33. The base station of claim 32, wherein the base station is further operative to attempt to derive a true PZID from the dummy PZID received from the mobile station, and, if the attempt is successful, include the derived true PZID in a packet-switched re-registration message sent by the base station to initiate the packet-switched re-registration of the mobile station.

34. The base station of claim 24, wherein the one or more dummy network identification parameters includes a dummy value for at least one of a System Identification (SID), a Network Identification (NID), and a Packet Zone Identification (PZID).

35. The base station of claim 34, wherein the first message includes a dummy value for at least one of the SID and NID, and includes a true value for the PZID, such that the mobile station recognizes a SID/NID mismatch at the end of the active voice call based on resumed monitoring of an overhead channel transmitted by the base station on which true network identification parameters are broadcast by the base station.

36. The base station of claim 24, wherein the one or more dummy network identification parameters includes a dummy PZID value associated with the base station, and wherein the mobile station broadcasts a true PZID value on one or more overhead channels, such that the mobile station obtains the true PZID value for the base station based on monitoring the one or more overhead channels after ending the active voice call.

37. The base station of claim 36, wherein the base station receives an origination message (OM) from the mobile station after the voice call ends, said OM generated by the mobile station responsive to the mobile station obtaining the true PZID value, and wherein the mobile station includes the dummy PZID value associated with the base station in the OM.

38. The base station of claim 37, wherein the base station:

recognizes the dummy PZID value included in the OM as matching the dummy PZID value associated with the base station; and

suppresses packet data re-registration of the mobile station.

39. The base station of claim 37, wherein the base station initiates circuit-switched re-registration of the mobile station responsive to receiving the OM.

40. The base station of claim 24, wherein the base station transmits the first message only if the hard handoff is an inter-MSC handoff.

41. The base station of claim 40, wherein the base station determines whether the hard handoff is an inter-MSC handoff.

42. A mobile switching center (MSC) supporting concurrent circuit-switched and packet-switched services for use in a wireless communication network, the MSC operative to:

receive a given mobile station in a hard handoff while the mobile station is engaged in an active voice call; and

transmit a first message including one or more dummy network identification parameters to the mobile station during the active voice call to force re-registration of the mobile station after the active voice call ends.

43. The MSC of claim 42, wherein the MSC transmits the first message to the mobile station only if the hard handoff is an inter-MSC handoff.

44. The MSC of claim 43, wherein the MSC determines whether the hard handoff is an inter-MSC handoff based on inter-MSC signaling.

45. The MSC of claim 43, wherein the MSC determines whether the hard handoff is an inter-MSC handoff based on receiving an IS-41 signaling message.

46. The MSC of claim 42, wherein the MSC transmits the first message to the mobile station via a target base station controlled by the MSC.

47. The MSC of claim 46, wherein the MSC transmits the first message to the mobile station after the target base station completes handoff processing associated with receiving the mobile station in hard handoff.