Communications session management

• US 20100075685A1
• Filed: 05/11/2005
• Published: 03/25/2010
• Est. Priority Date: 05/11/2005
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Axnäs, Johan
• Granted Patent: US 8,135,003 B2
• Time in Patent Office: Days
• US Class Current: 455/450
• CPC Class Codes: H04L 1/0001 Systems modifying transmission characteristics according to link quality, e.g. power backoff adaptive data allocation for multicarrier modulation H04L5/0044; controlling transmission power for radio systems H04W52/04
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/04 using frequency diversity
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04L 1/1819 with retransmission of additional or different redundancy
• CPC Class Codes: H04L 1/1867 Arrangements specially adapted for the transmitter end
• CPC Class Codes: H04L 1/1893 Physical mapping arrangements physical resource mapping in general H04L5/00
• CPC Class Codes: H04L 2001/0093 Point-to-multipoint
• CPC Class Codes: H04W 4/06 Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/27 between access points
• CPC Class Codes: H04W 76/15 Setup of multiple wireless link connections

Abstract

A scheduling algorithm is disclosed that allows mobile units, participating in an ongoing communications session, to temporary perform channel-demanding communications operations without ending the session and that is useful in the case of no free radio channels. The algorithm is based on selecting a radio channel for transmitting a radio block based on information of a previous radio channel, no which a previous radio block has been transmitted. The radio block and the previous radio block are based on common information. A mobile unit participating in the communications session selects whether to perform any channel-demanding communications operations on the selected radio channel. By limiting any such other channel-demanding operations to only the selected radio channel, the probability of loss of useful data for the mobile unit during the communications session is minimized.

Claims

1-26. -26. (canceled)

27. A method of enabling, during an ongoing communications session involving transmission of radio blocks to a mobile unit on a set of multiple available radio channels, other temporary channel-demanding communications operations for said mobile unit, said method comprising selecting a radio channel from said radio channel set for transmitting a radio block based on information of a previous radio channel, on which a previous radio block has been transmitted to said mobile unit, said radio block and said previous radio block being based on common information, wherein said mobile unit is capable of performing said other communications operations on said selected radio channel with reduced probability of loss of data for said communications session.

28. The method according to claim 27, further comprising transmitting said radio block on said selected radio channel.

29. The method according to claim 27, wherein said selecting step comprises selecting said radio channel based on said information and based on quality data representing the quality of a communications link between said mobile unit and a network node transmitting said radio blocks.

30. The method according to claim 29, further comprising:

organizing said multiple radio channels of said set into at least a first radio channel subset and a second radio channel subset, wherein said previous radio channel belongs to said first subset; and

comparing said quality data with a minimum quality threshold, said selecting step comprises i) selecting said radio channel from said second subset based on said information if said quality data exceeds said minimum quality threshold and ii) selecting said radio channel from said first subset based on said information if said quality data is smaller than said minimum quality threshold.

31. The method according to claim 27, further comprising organizing said multiple radio channels of said set into at least a first radio channel subset and a second radio channel subset, wherein said previous radio channel belongs to said first subset, and said selecting step comprises selecting said radio channel from said second subset based on said information.

32. The method according to claim 27, further comprising organizing said multiple radio channels of said set into at least a first radio channel subset and a second channel subset, wherein said previous radio channel belongs to said first subset, and said selecting step comprises selecting said radio channel from said first subset based on said information.

33. The method according to claim 32, wherein radio blocks are grouped into block frames, each block frame comprises multiple radio blocks and is assigned a radio channel subset selected from said at least first and second subset, said selecting step comprises the steps of:

identifying a radio channel subset assigned to a block frame to which said radio block belongs based on said information; and

selecting said radio channel from said identified radio channel subset.

37. The method according to claim 27, wherein said temporary communications operations comprise at least one of:

said mobile unit setting up a temporary block flow;

said mobile unit listening to a control channel; and

said mobile unit performing neighbor cell signal measurements.

38. The method according to claim 37, wherein said temporary block flow comprises at least one of:

said mobile unit sending a data message; and

said mobile unit performing a wireless application protocol interaction.

39. The method according to claim 27, wherein said ongoing communications session is a multimedia broadcast multicast communications session.

40. The method according to claim 27, wherein said radio block comprises the same information bits as said previous radio block.

34. A method of managing a communications session involving reception of radio blocks by a mobile unit on a set of multiple available radio channels, said method comprising said mobile unit performing other channel-demanding communications operations, during said communications session, on a radio channel on which a radio block is expected to be received, where said radio channel being selected based on information of a previous radio channel, on which a previous radio block has been received in order to reduce the probability of loss of data for said communications session, wherein said radio block and said previous radio block being based on common information.

35. The method according to claim 34, further comprising said mobile unit receiving said information from a network node transmitting said radio blocks.

36. The method according to claim 34, wherein said previous radio block has been successfully received by said mobile unit.

41. A system for enabling, during an ongoing communications session involving transmission of radio blocks to a mobile unit on a set of multiple available radio channels, other temporary channel-demanding communications operations for said mobile unit, said system comprising means for selecting a radio channel from said radio channel set for transmitting a radio block based on information of a previous radio channel on which a previous radio block has been transmitted, said radio block and said previous radio block being based on common information, wherein said mobile unit is capable of performing said other communications operations on said selected radio channel with reduced probability of loss of data for said communications session.

42. The system according to claim 41, wherein said selecting means is configured for selecting said radio channel based on said information and based on quality data representing the quality of a communications link between said mobile unit and a network node transmitting said radio blocks.

43. The system according to claim 42, further comprising:

means for organizing said multiple radio channels of said set into at least a first radio channel subset and a second radio channel subset, wherein said previous radio channel belongs to said first subset; and

means for comparing said quality data with a minimum quality threshold, said selecting means is configured for i) selecting said radio channel from said second subset based on said information if said quality data exceeds said minimum quality threshold as determined by said comparing means and ii) selecting said radio channel from said first subset based on said information if said quality data is smaller than said minimum quality threshold as determined by said comparing means.

44. The system according to claim 41, further comprising means for organizing said multiple radio channels of said set into at least a first radio channel subset and a second radio channel subset, wherein said previous radio channel belongs to said first subset, and said selecting means is configured for selecting said radio channel from said second subset based on said information.

45. The system according to claim 41, further comprising means for organizing said multiple radio channels of said set into at least a first radio channel subset and a second channel subset, wherein said previous radio channel belongs to said first subset, and said selecting means is configured for selecting said radio channel from said first subset based on said information.

46. The system according to claim 45, wherein radio blocks are grouped into block frames, each block frame comprises multiple radio blocks and is assigned a radio channel subset selected from said at least first and second subset, said selecting means comprises:

means for identifying a radio channel subset assigned to a block frame to which said radio block belongs based on said information; and

means for selecting said radio channel from said identified radio channel subset.

47. A network node comprising:

a system for enabling, during an ongoing communications session, other temporary communications operations for a mobile unit according to claim 41; and

a transmitter for transmitting said radio block on said selected radio channel.

48. A mobile unit adapted for conducting a communications service, involving reception of radio blocks on a set of multiple available radio channels, with a network node in a communications system, said mobile unit comprising:

a receiver for receiving a previous radio block from said network node on a previous radio channel of said radio channel set; and

means for performing other communications operations, during said communications session, on a radio channel on which a radio block is expected to be received from said network node, where said radio channel is selected based on information of said previous radio channel, on which said previous radio block has been received by said receiver, in order to reduce the probability of loss of data for said communications session, wherein said radio block and said previous radio block being based on common information.

49. The mobile unit according to claim 48, wherein said previously radio block has been successfully received by said receiver.

50. The mobile unit according to claim 48, wherein said radio block is a retransmitted version of said previous radio block.

51. The mobile unit according to claim 48, wherein said receiver is configured for receiving a notification of said radio channel from said network node.

52. The mobile unit according to claim 48, further comprising means for selecting said radio channel based on said information.