Method and Arrangement for Handover or Cell Reselection Evaluation

• US 20110045833A1
• Filed: 03/31/2009
• Published: 02/24/2011
• Est. Priority Date: 04/29/2008
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Kazmi, Muhammad
• Granted Patent: US 8,649,790 B2
• Time in Patent Office: Days
• US Class Current: 455/436
• CPC Class Codes: H04W 36/24 Reselection being triggered by specific parameters
• CPC Class Codes: H04W 36/32 by location or mobility data, e.g. speed data

Abstract

A method in a base station for configuring a wireless terminal for performing a cell reselection or handover evaluation process “evaluation process” is provided. The wireless terminal is arranged to perform multiple evaluation processes parallel to each other, which multiple evaluation processes are governed by different set of mobility parameters. The base station determines (302) whether or not the multiple parallel evaluation processes, shall be used by the wireless terminal, based on the result of an establishment (301) of the mobility state, such as movement speed, of the wireless terminal. The base station signals (306) an identifier to the wireless terminal (110), which identifier identifies the determined whether or not the multiple parallel evaluation processes shall be configured to be used by the wireless terminal for evaluating cell reselection or handover.

Claims

1-34. -34. (canceled)

35. A method in a base station for configuring a wireless terminal for performing a cell reselection or handover evaluation process, the base station comprised in a radio access network and configured to communicate with the wireless terminal over an air interface, the wireless terminal arranged to perform multiple evaluation processes in parallel that are governed by different sets of mobility parameters, the method comprising:

establishing a mobility state of the wireless terminal,

determining, based on the established mobility state of the wireless terminal, whether or not the terminal shall perform any of the multiple evaluation processes in parallel for evaluating cell reselection or handover, and

signaling an identifier to the wireless terminal that indicates said determination to the terminal.

36. The method of claim 35, further comprising, if determined that the wireless terminal shall perform at least some of the multiple evaluation processes in parallel, selecting at least two of the multiple evaluation processes based on the established mobility state of the wireless terminal, each of the selected processes comprising one or more mobility parameters that shall be used by the wireless terminal, and wherein the identifier further identifies the at least two selected evaluation processes.

37. The method of claim 35, further comprising, if determined that the wireless terminal shall not perform any of the multiple evaluation processes in parallel, selecting one of the multiple evaluation processes based on the established mobility state of the wireless terminal, the selected process comprising one or more mobility parameters that shall be used by the wireless terminal, and wherein the identifier further identifies the selected one of the multiple evaluation processes.

38. The method of claim 35, wherein the wireless terminal is further configured to perform a default cell reselection or handover evaluation process that is governed by one set of default mobility parameters, wherein the method further comprises, if determined that the wireless terminal shall not perform any of the multiple evaluation processes in parallel, selecting the default evaluation process based on the established mobility state of the wireless terminal, and wherein the identifier further identifies the selected default evaluation process.

39. The method of claim 35, wherein the multiple evaluation processes are associated with respective speeds that the wireless terminal moves with, and wherein establishing the mobility state of the wireless terminal comprises establishing the speed with which the wireless terminal moves.

40. The method of claim 39, wherein the multiple evaluation processes comprise at least one of a first evaluation process associated with low speed of the wireless terminal, a second evaluation process associated with medium speed of the wireless terminal, and a third evaluation process associated with high speed of the wireless terminal.

41. The method of claim 35, wherein the mobility parameters are any one or more of time average window, Treselection, Qhyst, time hysteresis and signal hysteresis.

42. The method of claim 35, wherein the method configures a wireless terminal for performing a cell reselection evaluation process, wherein the wireless terminal is in idle mode, and wherein the identifier is signaled to the wireless terminal via a broadcast channel.

43. The method of claim 35, wherein the method configures a wireless terminal for performing a handover evaluation process, wherein the wireless terminal is in connected mode, and wherein the identifier is signaled to the wireless terminal via a wireless terminal specific channel.

44. A method in a wireless terminal for being configured by a base station to perform a cell reselection or handover evaluation process, the base station comprised in a radio access network, the wireless terminal configured to communicate with the base station over an air interface and arranged to perform multiple evaluation processes in parallel that are governed by different sets of mobility parameters, the method comprising:

receiving an identifier from the base station that identifies whether or not the wireless terminal shall perform any of the multiple evaluation processes in parallel for evaluating cell reselection or handover, as determined by the base station based on a mobility state of the wireless terminal,

configuring the wireless terminal to perform one or more of the evaluation processes for evaluating cell reselection or handover according to the received identifier.

45. The method of claim 44,

wherein the identifier indicates that the wireless terminal shall perform at least some of the multiple evaluation processes in parallel, and

wherein the identifier further identifies at least two of the multiple evaluation processes that the wireless terminal shall perform for evaluating cell reselection or handover, the at least two evaluation processes having been selected by the base station based on the mobility state of the wireless terminal, and each comprising one or more mobility parameters that shall be used by the wireless terminal.

46. The method of claim 44,

wherein the identifier indicates that the wireless terminal shall not perform any of the multiple evaluation processes in parallel, and

wherein the identifier further identifies one of the multiple evaluation processes that the wireless terminal shall perform for evaluating cell reselection or handover, the identified evaluation process having been selected by the base station based on the mobility state of the wireless terminal and comprising one or more mobility parameters that shall be used by the wireless terminal for evaluating cell reselection or handover.

47. The method of claim 44,

wherein the wireless terminal is further configured to perform a default cell reselection or handover evaluation process that is governed by one set of default mobility parameters,

wherein the identifier indicates that the wireless terminal shall not perform any of the multiple evaluation processes in parallel, and

wherein the identifier further identifies that the wireless terminal shall perform the default evaluation process for evaluating cell reselection or handover, the default evaluation process having been selected by the base station, based on the mobility state of the wireless terminal.

48. The method of claim 44, wherein the multiple evaluation processes are associated with respective speeds that the wireless terminal moves with, and wherein the mobility state of the wireless terminal was established by the base station by establishing the speed with which the wireless terminal moves.

49. The method of claim 48, wherein the multiple evaluation processes comprise at least one of a first evaluation process associated with low speed of the wireless terminal, a second evaluation process associated with medium speed of the wireless terminal, and a third evaluation process associated with high speed of the wireless terminal.

50. The method of claim 44, wherein the mobility parameters are any one or more of time average window, Treselection, Qhyst, time hysteresis and signal hysteresis.

51. The method of claim 44, wherein the method is performed for evaluating cell reselection, wherein the wireless terminal is in idle mode, and wherein the identifier is received from the base station via a broadcast channel.

52. The method of claim 44, wherein the method is performed for evaluating handover, wherein the wireless terminal is in connected mode, and wherein the identifier is received from the base station via a wireless terminal specific channel.

53. A base station arranged to configure a wireless terminal for performing a cell reselection, or handover, evaluation process, the base station comprised in a radio access network and configured to communicate with the wireless terminal over an air interface, the wireless terminal arranged to perform multiple evaluation processes in parallel that are governed by different sets of mobility parameters, the base station comprising:

an evaluation process selector configured to;

establish a mobility state of the wireless terminal,

determine, based on the established mobility state of the wireless terminal, whether or not the terminal shall perform any of the multiple evaluation processes in parallel for evaluating cell reselection or handover, and

a transceiver configured to signal an identifier to the wireless terminal that indicates said determination to the terminal.

54. The base station of claim 53, wherein the evaluation process selector is further configured to, if determined that the wireless terminal shall perform at least some of the multiple evaluation processes in parallel, select at least two of the multiple evaluation processes based on the established mobility state of the wireless terminal, each of the selected processes comprising one or more mobility parameters that shall be used by the wireless terminal, and wherein the identifier further identifies the at least two selected evaluation processes.

55. The base station of claim 53, wherein the evaluation process selector is further configured to, if determined that the wireless terminal shall not perform any of the multiple evaluation processes in parallel, select one of the multiple evaluation processes based on the established mobility state of the wireless terminal, the selected process comprising one or more mobility parameters that shall be used by the wireless terminal, and wherein the identifier further identifies the selected one of the multiple evaluation processes.

56. The base station of claim 53, wherein the wireless terminal is further configured to perform a default cell reselection or handover evaluation process that is governed by one set of default mobility parameters, wherein the evaluation process selector is further configured to, if determined that the wireless terminal shall not perform any of the multiple evaluation processes in parallel, select the default evaluation process based on the established mobility state of the wireless terminal, and wherein the identifier further identifies the selected default evaluation process.

57. The base station of claim 53, wherein the multiple evaluation processes are associated with respective speeds that the wireless terminal moves with, and wherein the evaluation process selector is configured to establish the mobility state of the wireless terminal by establishing the speed with which the wireless terminal moves.

58. The base station of claim 57, wherein the multiple parallel evaluation processes comprise at least one of a first evaluation process associated with low speed of the wireless terminal, a second evaluation process associated with medium speed of the wireless terminal, and a third evaluation process associated with high speed of the wireless terminal.

59. The base station of claim 53, wherein the mobility parameters are any one or more of time average window, Treselection, Qhyst, time hysteresis and signal hysteresis.

60. The base station of claim 53, wherein the transceiver is further configured to signal the identifier to the wireless terminal via a broadcast channel or via a wireless terminal specific channel.

61. A wireless terminal arranged to be configured by a base station for performing a cell reselection, or handover, evaluation process, the base station comprised in a radio access network, the wireless terminal configured to communicate with the base station over an air interface and arranged to perform multiple evaluation processes in parallel that are governed by different sets of mobility parameters, the wireless terminal comprising:

a transceiver configured to receive an identifier from the base station that indicates whether or not the wireless terminal shall perform any of the multiple evaluation processes in parallel for evaluating cell reselection or handover, as determined by the base station based on a mobility state of the wireless terminal, and

a processor arranged to configure the wireless terminal to perform one or more of the evaluation processes for evaluating cell reselection or handover according to the received identifier.

62. The wireless terminal of claim 61,

wherein the identifier indicates that the wireless terminal shall perform at least some of the multiple evaluation processes in parallel, and

wherein the identifier further identifies at least two of the multiple evaluation processes that the wireless terminal shall perform for evaluating cell reselection or handover, the at least two evaluation processes having been selected by the base station based on the mobility state of the wireless terminal, and each comprising one or more mobility parameters that shall be used by the wireless terminal.

63. The wireless terminal of claim 61,

wherein the identifier indicates that the wireless terminal shall not perform any of the multiple evaluation processes in parallel, and

wherein the identifier further identifies one of the multiple evaluation processes that the wireless terminal shall perform for evaluating cell reselection or handover, the identified evaluation process having been selected by the base station based on the mobility state of the wireless terminal and comprising one or more mobility parameters that shall be used by the wireless terminal for evaluating cell reselection or handover.

64. The wireless terminal of claim 61,

wherein the wireless terminal is further configured to perform a default cell reselection or handover evaluation process that is governed by one set of default mobility parameters,

wherein the identifier indicates that the wireless terminal shall not perform any of the multiple evaluation processes in parallel, and

wherein the identifier further identifies that the wireless terminal shall perform the default evaluation process for evaluating cell reselection or handover, the default evaluation process having been selected by the base station, based on the mobility state of the wireless terminal.

65. The wireless terminal of claim 61, wherein the multiple evaluation processes are associated with respective speeds that the wireless terminal moves with, and wherein the mobility state of the wireless terminal was established by the base station by establishing the speed with which the wireless terminal moves.

66. The wireless terminal of claim 65, wherein the multiple evaluation processes comprise at least one of a first evaluation process associated with low speed of the wireless terminal, a second evaluation process associated with medium speed of the wireless terminal, and a third evaluation process associated with high speed of the wireless terminal.

67. The wireless terminal of claim 61, wherein the mobility parameters are any one or more of time average window, Treselection, Qhyst, time hysteresis and signal hysteresis.

68. The wireless terminal of claim 61, wherein the transceiver further is configured to receive the identifier from the base station via a broadcast channel or a wireless terminal specific channel.