Seamless call switching in a dual mode environment

• US 7,187,923 B2
• Filed: 11/19/2004
• Issued: 03/06/2007
• Est. Priority Date: 11/20/2003
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: Wormald, Christopher R., Mousseau, Gary P.
• Primary Examiner(s): BEAMER, TEMICA M
• Application Number:
  US10/992,934
• Publication Number:
  US 20050159153A1
• Time in Patent Office: 837 Days
• Field of Search: 455/432.1, 455/432.2, 455/436, 455/552.1, 455/553.1, 455/67.13, 455/416
• US Class Current: 455/416
• CPC Class Codes: H04W 36/0066 of control information between different types of networks in order to establish a new radio link in the target network
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection

Abstract

Methods and apparatus for providing a seamless switching of voice calls between different wireless networks are disclosed. In one illustrative example, a mobile communication device has a processor and one or more wireless transceivers coupled to the processor. The one or more wireless transceivers include a first transceiver portion operative in accordance with a first wireless network (e.g. a GSM/GPRS cellular network) and a second transceiver portion operative in accordance with a second wireless network (e.g. an 802.11 wireless network). A voice call is maintained between the mobile device and a communication terminal through call control equipment. The processor of the mobile device is operative to maintain voice communications for the voice call over a traffic channel established between the mobile device and the first wireless network using the first transceiver portion; cause a connecting call to be established with the communication terminal through the call control equipment in response to a predetermined condition, where the connecting call involves a traffic channel established between the second wireless network and the mobile device using the second transceiver portion; and after the connecting call is established, maintain voice communications for the voice call over the traffic channel established between the second wireless network and the mobile device.

Claims

1. A method for use by a mobile communication device in switching a voice call between two different wireless communication networks, the method comprising the steps of:

maintaining voice communications for a voice call with a communication terminal through call control equipment, the voice call involving a traffic channel established between a first wireless network and the mobile device with use of a first transceiver portion which operates in accordance with the first wireless network;

in response to identifying a predetermined condition, causing a message to be transmitted to the call control equipment for establishing a connecting call between the call control equipment and the mobile device, the connecting call involving a traffic channel established between a second wireless network and the mobile device using a second transceiver portion which operates in accordance with the second wireless network, the connecting call being made part of a conference call connection established at the call control equipment together with the voice call; and

maintaining voice communications for the voice call over the traffic channel established between the second wireless network and the mobile device.

2. The method of claim 1, wherein the first wireless network is operative in accordance with a cellular telecommunications network and the second wireless network is operative in accordance with an 802.11 based wireless network.

3. The method of claim 1, wherein the first wireless network is operative in accordance with a first cellular telecommunications network and the second wireless network is operative in accordance with a second cellular telecommunications network different from the first cellular telecommunications network.

4. The method of claim 1,

wherein the mobile device is associated with a telephone number which, when dialed, causes the voice call to be routed to the call control equipment for the mobile device when it operates in a first wireless network comprising a cellular telecommunications network.

5. The method of claim 1, wherein the step of causing the message to be transmitted for establishing the connecting call comprises the further steps of:

causing a network switching message to be sent to the call control equipment;

receiving a call initiation message from the second wireless network for the connecting call in response to sending the network switching message to the call control equipment; and

causing a call answering message to be sent to the second wireless network based on receiving the call initiation message from the second wireless network, for thereby establishing the traffic channel between the second wireless network and the mobile device.

6. The method of claim 1, wherein the predetermined condition comprises one of a poor signal condition with the first wireless network, a predetermined signal detection from the second wireless network, and a user input signal at the mobile device.

7. The method of claim 1, wherein the step of causing the message to be transmitted for establishing the connecting call comprises the further steps of:

initiating the connecting call to the call control equipment by sending a call initiation message to the second wireless network.

8. The method of claim 1, further comprising:

causing the traffic channel with the first wireless network to be terminated after maintaining the voice communications with the second wireless network.

9. The method of claim 1, wherein the second wireless network is operative in accordance with a cellular telecommunications network and the first wireless network is operative in accordance with an 802.11 based wireless network.

10. A computer program product, comprising:

a storage medium;

computer instructions stored on the storage medium;

the computer instructions being executable by one or more processors of a mobile communication device for;

maintaining voice communications for a voice call with a communication terminal through call control equipment, the voice call involving a traffic channel established between a first wireless network and the mobile device with use of a first transceiver portion which operates in accordance with the first wireless network;

in response to identifying a predetermined condition;

causing a message to be transmitted to the call control equipment for establishing a connecting call between the call control equipment and the mobile device, the connecting call involving a traffic channel established between a second wireless network and the mobile device with use of a second transceiver portion which operates in accordance with the second wireless network, the connecting call being made part of a conference call connection established at the call control eQuipment together with the voice call; and

maintaining voice communications for the voice call over the traffic channel established between the second wireless network and the mobile device.

11. The computer program product of claim 10, wherein the first wireless network is operative in accordance with a cellular telecommunications network and the second wireless network is operative in accordance with an 802.11 based wireless network.

12. The computer program product of claim 10, wherein the second wireless network is operative in accordance with a cellular telecommunications network and the first wireless network is operative in accordance with an 802.11 based wireless network.

13. The computer program product of claim 10,

wherein the mobile device is associated with a telephone number which, when dialed, causes the voice call to be routed to the call control equipment for the mobile device when it operates in a first wireless network comprising a cellular telecommunications network.

14. The computer program product of claim 10, wherein the computer instructions are further executable for causing the message to be transmitted for establishing the connecting call by:

causing a network switching message to be sent to the call control equipment;

receiving a call initiation message from the second wireless network for the connecting call in response to sending the network switching message to the call control equipment; and

causing a call answering message to be sent to the second wireless network based on receiving the call initiation message from the second wireless network, for thereby establishing the traffic channel between the second wireless network and the mobile device.

15. The computer program product of claim 10, wherein the predetermined condition comprises one of a poor signal condition with the first wireless network, a predetermined signal detection from the second wireless network, and a user input signal at the mobile device.

16. The computer program product of claim 10, wherein the computer instructions are further executable for causing the message to be transmitted for establishing the connecting call by:

initiating the connecting call to the call control equipment by sending a call initiation message to the second wireless network.

17. The computer program product of claim 10, wherein the computer instructions are further executable for:

causing the traffic channel with the first wireless network to be terminated after maintaining the voice communications with the second wireless network.

18. The computer program product of claim 10, wherein the voice communications of the voice call comprises Voice over IP (VoIP) communication through one of the first and the second wireless networks.

19. A mobile communication device, comprising:

one or more processors;

one or more wireless transceiver coupled to the one or more processors;

the one or more wireless transceivers having a first transceiver portion operative in accordance with a first Wireless network and a second transceiver portion operative in accordance with a second wireless network;

the one or more processors being operative to;

maintain voice communications for a voice call with a communication terminal through call control equipment, the voice call involving a traffic channel established between the first wireless network and the mobile device with use of the first transceiver portion;

in response to identifying a predetermined condition, cause a message to be transmitted to the call control equipment for establishing a connecting call between the call control equipment and the mobile device, the connecting call involving a traffic channel established between a second wireless network and the mobile device with use of the second transceiver portion, the connecting call being made part of a conference call connection established at the call control eciuipment together with the voice call; and

maintain voice communications for the voice call over the traffic channel established between the second wireless network and the mobile device.

20. The mobile device of claim 19, wherein the first wireless network is operative in accordance with a cellular telecommunications network and the second wireless network is operative in accordance with an 802.11 based wireless network.

21. The mobile device of claim 19, wherein the first wireless network is operative in accordance with a first cellular telecommunications network and the second wireless network is operative in accordance with a second cellular telecommunications network different from the first cellular telecommunications network.

22. The mobile device of claim 19,

wherein the mobile device is associated with a telephone number which, when dialed, causes the voice call to be routed to the call control equipment for the mobile device when it operates in a first wireless network comprising a cellular telecommunications network.

23. The mobile device of claim 19, wherein the one or more processors are further operative to cause the message to be transmitted for establishing the connecting call by:

causing a network switching message to be sent to the call control equipment;

receiving a call initiation message from the second wireless network for the connecting call in response to sending the network switching message to the call control equipment; and

causing a call answering message to be sent to the second wireless network based on receiving the call initiation message from the second wireless network, for thereby establishing the traffic channel between the second wireless network and the mobile device.

24. The mobile device of claim 19, wherein the predetermined condition comprises one of a poor signal condition with the first wireless network, a predetermined signal detection from the second wireless network, and a user input signal at the mobile device.

25. The mobile device of claim 19, wherein the one or more processors are further operative to cause the message to be transmitted for establishing the connecting call by:

initiating the connecting call to the call control equipment by sending a call initiation message to the second wireless network.

26. The mobile device of claim 19, wherein the one or more processors are further operative to:

cause the traffic channel with the first wireless network to be terminated after maintaining the voice communications with the second wireless network.

27. The mobile device of claim 19,

wherein the second wireless network is operative in accordance with a cellular telecommunications network and the first wireless network is operative in accordance with an 802.11 based wireless network.

28. A method for use by call control equipment in switching a voice call involving a mobile communication device between two different wireless communication networks, the method comprising the steps of:

maintaining a voice call between a mobile device and a communication terminal through the call control equipment, the voice call involving a traffic channel established between a first wireless network and the mobile device;

receiving a message from the mobile device for establishing a connecting call;

in response to receiving the message, causing a connecting call to be established between the call control equipment and the mobile device during the voice call, the connecting call involving a traffic channel established between a second wireless network and the mobile device; and

causing the connecting call to be connected with the voice call in a conference call connection at the call control equipment so that voice communications for the voice call are maintained over the traffic channel between the second wireless network and the mobile device.

29. The method of claim 28, wherein the first wireless network is operative in accordance with a cellular telecommunications network and the second wireless network is operative in accordance with an 802.11 based wireless network.

30. The method of claim 28, wherein the first wireless network is operative in accordance with a first cellular telecommunications network and the second wireless network is operative in accordance with a second cellular telecommunications network different from the first cellular telecommunications network.

31. The method of claim 28, wherein the step of causing the connecting call to be established comprises:

placing the connecting call with the mobile device.

32. The method of claim 28,

wherein the mobile device is associated with a telephone number which, when dialed, causes the voice call to be routed to the call control equipment for the mobile device when it operates in a first wireless network comprising a cellular telecommunications network.

33. The method of claim 28, wherein the steps of receiving the message and causing the connecting call to be established further comprises:

receiving the connecting call from the mobile device; and

causing the connecting call with the mobile device to be answered.

34. The method of claim 28, further comprising:

causing the traffic channel with the first wireless network to be terminated after causing the connecting call to be connected with the voice call.

35. The method of claim 28,

wherein the second wireless network is operative in accordance with a cellular telecommunications network and the first wireless network is operative in accordance with an 802.11 based wireless network.

36. A computer program product, comprising:

a storage medium;

computer instructions stored on the storage medium;

the computer instructions being executable by one or more processors of call control equipment for;

maintaining a voice call between a mobile device and a communication terminal through the call control equipment, the voice call involving a traffic channel established between a first wireless network and the mobile device;

receiving a message from the mobile device for establishing a connecting call;

in response to receiving the message, causing a connecting call to be established between the call control equipment and the mobile device during the voice call, the connecting call involving a traffic channel established between the second wireless network and the mobile device; and

causing the connecting call to be connected with the voice call in a conference call connection at the call control equipment so that voice communications for the voice call are maintained over the traffic channel between the second wireless network and the mobile device.

37. The computer program product of claim 36, wherein the first wireless network is operative in accordance with a cellular telecommunications network and the second wireless network is operative in accordance with an 802.11 based wireless network.

38. The computer program product of claim 36, wherein the first wireless network is operative in accordance with a first cellular telecommunications network and the second wireless network is operative in accordance with a second cellular telecommunications network different from the first cellular telecommunications network.

39. The computer program product of claim 36, wherein the computer instructions are further executable for causing the connecting call to be established by:

placing the connecting call with the mobile device.

40. The computer program product of claim 36,

wherein the mobile device is associated with a telephone number which, when dialed, causes the voice call to be routed to the call control equipment for the mobile device when it operates in a first wireless network comprising a cellular telecommunications network.

41. The computer program product of claim 36, wherein the computer instructions are further executable for receiving the message and causing the connecting call to be established by:

receiving the connecting call from the mobile device; and

causing the connecting call with the mobile device to be answered.

42. The computer program product of claim 36, wherein the computer instructions are further executable for:

causing the traffic channel with the first wireless network to be terminated after causing the connecting call to be connected with the voice call.

43. The computer program product of claim 36,

wherein the second wireless network is operative in accordance with a cellular telecommunications network and the first wireless network is operative in accordance with an 802.11 based wireless network.

44. Call control equipment, comprising:

one or more processors;

memory coupled to the one or more processors;

computer instructions stored in the memory;

the computer instructions being executable by the one or more processors for;

maintaining a voice call between a mobile device and a communication terminal through the call control equipment, the voice call involving a traffic channel established between a first wireless network and the mobile device;

receiving a message from the mobile device for establishing a connecting call;

in response to receiving the message, causing a connecting call to be established between the call control equipment and the mobile device during the voice call, the connecting call involving a traffic channel established between a second wireless network and the mobile device; and

causing the connecting call to be connected with the voice call in a conference call connection at the call control equipment so that voice communications for the voice call are maintained over the traffic channel between the second wireless network and the mobile device.

45. The call control equipment of claim 44, wherein the first wireless network is operative in accordance with a cellular telecommunications network and the second wireless network is operative in accordance with an 802.11 based wireless network.

46. The call control equipment of claim 44, wherein the first wireless network is operative in accordance with a first cellular telecommunications network and the second wireless network is operative in accordance with a second cellular telecommunications network different from the first cellular telecommunications network.

47. The call control equipment of claim 44, wherein the computer instructions are further executable for causing the connecting call to be established by:

placing the connecting call with the mobile device.

48. The call control equipment of claim 44,

wherein the second wireless network is operative in accordance with a cellular telecommunications network and the first wireless network is operative in accordance with an 802.11 based wireless network.

49. The call control equipment of claim 44, wherein the computer, instructions are further executable for receiving the message and causing the connecting call to be established by:

receiving the connecting call from the mobile device; and

causing the connecting call with the mobile device to be answered.

50. The call control equipment of claim 44, wherein the computer instructions are further executable for:

causing the traffic channel with the first wireless network to be terminated after causing the connecting call to be connected with the voice call.

51. The call control equipment of claim 44, further comprising a call control server having the one or more processors and coupled within the second wireless network.