Handover methods and apparatus for mobile communication devices

• US 20070167165A1
• Filed: 01/13/2006
• Published: 07/19/2007
• Est. Priority Date: 01/13/2006
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: Yang, Lianghua, Huang, Wenjie
• Granted Patent: US 8,060,098 B2
• Time in Patent Office: Days
• US Class Current: 455/439
• CPC Class Codes: H04W 36/0055 Transmission or use of information for re-establishing the radio link

Abstract

A mobile communication device assists in a handover procedure between a first base station and a second base station using reliable and efficient techniques. The mobile device has a wireless transceiver and one or more processors coupled to the wireless transceiver. In one illustrative example, the one or more processors of the mobile device are operative to maintain a voice or data call over a traffic channel with use of the wireless transceiver; cause handover information of the handover procedure to be transmitted over a first control channel (e.g. SACCH) with use of the wireless transceiver during the voice or data call; and cause the same handover information of the handover procedure to be transmitted over a second control channel (e.g. FACCH) during the voice or data call. Further, the one or more processors may be operative to cause a message for the handover procedure to be transmitted in a layer-2 (L2) frame with use of the wireless transceiver during the voice or data call; and cause updated system information (e.g. an updated BA list) to be transmitted in the L2 frame with use of the wireless transceiver during the voice or data call.

Claims

1. A method for use in performing a handover procedure between a first base station and a second base station for a mobile communication device, the method comprising the acts of:

maintaining a voice or data call over a traffic channel;

causing handover information of the handover procedure to be transmitted over a first control channel during the voice or data call; and

causing the same handover information of the handover procedure to be transmitted over a second control channel during the voice or data call.

2. The method of claim 1, further comprising:

encoding the handover information of the handover procedure in accordance with a first encoding format for transmission over the first control channel; and

encoding the same handover information of the handover procedure in accordance with a second encoding format for transmission over the second control channel.

3. The method of claim 1, wherein the step of causing the handover information of the handover procedure to be transmitted over the first control channel is performed over a first time period and the step of causing the same handover information of the handover procedure to be transmitted over the second control channel is performed over a second time period which overlaps with the first time period.

4. The method of claim 1, wherein the handover information of the handover procedure over the first control channel is spread over a first time period and the same handover information of the handover procedure over the second control channel is spread over a second time period which is greater than the first time period.

5. The method of claim 1, wherein the first control channel comprises a fast associated control channel (FACCH) and the second control channel comprises a slow associated control channel (SACCH).

6. The method of claim 1, wherein the handover information comprises a set asynchronous balance mode (SABM) message.

7. The method of claim 1, which is performed by the mobile communication device.

8. The method of claim 1, which is performed by a base station.

9. The method of claim 1, further comprising:

monitoring the first control channel for handover information of the handover procedure during the voice or data call;

monitoring the second control channel for the same handover information of the handover procedure during the voice or data call; and

when there is a failure in receiving the handover information of the handover procedure over the first control channel;

processing the handover information of the handover procedure received over the second control channel for performing the handover procedure.

10. The method of claim 1, further comprising:

monitoring the first control channel for handover information of the handover procedure during the voice or data call;

monitoring the second control channel for the same handover information of the handover procedure during the voice or data call;

when there is a failure in receiving the handover information of the handover procedure over the first control channel;

processing the handover information of the handover procedure received over the second control channel for performing the handover procedure; and

when there is a failure in receiving the handover information of the handover procedure over the second control channel;

processing the handover information of the handover procedure received over the first control channel for performing the handover procedure.

11. A mobile communication device, comprising:

a wireless transceiver;

one or more processors coupled to the wireless transceiver;

the one or more processors being operative to;

maintain a voice or data call over a traffic channel with use of the wireless transceiver;

cause handover information of a handover procedure to be transmitted over a first control channel with use of the wireless transceiver during the voice or data call; and

cause the same handover information of the handover procedure to be transmitted over a second control channel during the voice or data call.

12. The mobile communication device of claim 11, wherein the one or more processors are further operative to:

encode the handover information of the handover procedure in accordance with a first encoding format for transmission over the first control channel; and

encode the same handover information of the handover procedure in accordance with a second encoding format for transmission over the second control channel.

13. The mobile communication device of claim 11, wherein the one or more processors are further operative to cause the handover information of the handover procedure to be transmitted over the first control channel over a first time period and cause the same handover information of the handover procedure to be transmitted over the second control channel over a second time period which overlaps with the first time period.

14. The mobile communication device of claim 11, wherein the one or more processors are further operative to cause the handover information of the handover procedure over the first control channel to be spread over a first time period and the same handover information of the handover procedure over the second control channel to be spread over a second time period which is greater than the first time period.

15. The mobile communication device of claim 11, wherein the first control channel comprises a fast associated control channel (FACCH) and the second control channel comprises a slow associated control channel (SACCH).

16. The mobile communication device of claim 11, wherein the handover information comprises a set asynchronous balance mode (SABM) message.

17. A method for use in performing a handover procedure for a mobile communication device which operates in a wireless communication network, comprising:

monitoring a first control channel for handover information of the handover procedure during a voice or data call;

monitoring a second control channel for the same handover information of the handover procedure during the voice or data call; and

when there is a failure in receiving the handover information of the handover procedure over the first control channel;

processing the handover information of the handover procedure received over the second control channel for performing the handover procedure.

18. The method of claim 17, further comprising:

when there is a failure in receiving the handover information of the handover procedure over the second control channel;

processing the handover information of the handover procedure received over the first control channel for performing the handover procedure.

19. The method of claim 17, wherein the step of causing the handover information of the handover procedure to be transmitted over the first control channel is performed over a first time period and the step of causing the same handover information of the handover procedure to be transmitted over the second control channel is performed over a second time period which overlaps with the first time period.

20. The method of claim 17, wherein the handover information of the handover. procedure over the first control channel is spread over a first time period and the same handover information of the handover procedure over the second control channel is spread over a second time period which is greater than the first time period.

21. The method of claim 17, wherein the first control channel comprises a fast associated control channel (FACCH) and the second control channel comprises a slow associated control channel (SACCH).

22. The method of claim 17, wherein the handover information comprises a set asynchronous balance mode (SABM) message.

23. The method of claim 17, which is performed by the mobile communication device.

24. The method of claim 17, which is performed by a base station.

25. A mobile communication device, comprising:

a wireless transceiver;

one or more processors coupled to the wireless transceiver;

the one or more processors being operative to;

monitor a first control channel for handover information of the handover procedure with use of the wireless transceiver during a voice or data call;

monitor a second control channel for the same handover information of the handover procedure with use of the wireless transceiver during the voice or data call; and

process the handover information of the handover procedure received over the second control channel for performing the handover procedure when there is a failure in receiving the handover information of the handover procedure over the first control channel.

26. The mobile communication device of claim 25, wherein the one or more processors are further operative to process the handover information of the handover procedure received over the first control channel for performing the handover procedure when there is a failure in receiving the handover information of the handover procedure over the second control channel.

27. The mobile communication device of claim 25, wherein the one or more processors are further operative to cause the handover information of the handover procedure to be transmitted over the first control channel over a first time period and cause the same handover information of the handover procedure to be transmitted over the second control channel over a second time period which overlaps with the first time period.

28. The mobile communication device of claim 25, wherein the one or more processors are further operative to cause the handover information of the handover procedure over the first control channel to be spread over a first time period and cause the same handover information of the handover procedure over the second control channel to be spread over a second time period which is greater than the first time period.

29. The mobile communication device of claim 25, wherein the first control channel comprises a fast associated control channel (FACCH) and the second control channel comprises a slow associated control channel (SACCH).

30. The mobile communication device of claim 25, wherein the handover information comprises a set asynchronous balance mode (SABM) message.

31. A method for use in performing a handover procedure between a first base station and a second base station for a mobile communication device, the method comprising the acts of:

maintaining a voice or data call over a traffic channel;

causing a message for the handover procedure to be transmitted in a frame during the voice or data call; and

causing updated system information to be transmitted in the frame during the voice or data call.

32. The method of claim 31, wherein the frame comprises a layer-2 (L2) frame.

33. The method of claim 31, wherein the message comprises one of a physical information type message and a handover complete acknowledgement type message.

34. The method of claim 31, wherein the updated system information comprises a neighbor cell (BA) list.

35. The method of claim 31, wherein the updated system information comprises one of cell identity information, location area identity information, cell options information, and network colour code (NCC) permission information.

36. The method of claim 31, which is performed by the mobile station.

37. The method of claim 31, wherein the message is transmitted over a fast associated control channel (FACCH).

38. A mobile communication device, comprising:

a wireless transceiver;

one or more processors coupled to the wireless transceiver;

the one or more processors being operative to;

maintain a voice or data call over a traffic channel with use of the wireless transceiver;

cause a message for the handover procedure to be transmitted in a frame with use of the wireless transceiver during the voice or data call; and

cause updated system information to be transmitted in the frame with use of the wireless transceiver during the voice or data call.

39. The mobile communication device of claim 38, wherein the frame comprises a layer-2 (L2) frame.

40. The mobile communication device of claim 38, wherein the message comprises one of a physical information type message and a handover complete acknowledgement type message.

41. The mobile communication of claim 38, wherein the updated system information comprises a neighbor cell (BA) list.

42. The mobile communication device of claim 38, wherein the updated system information comprises one of cell identity information, location area identity information, cell options information, and network colour code (NCC) permission information.

43. The mobile communication device of claim 38, wherein the message is transmitted over a forward associated control channel (FACCH).