Idle Mode Hybrid Mobility Procedure in a Heterogeneous Network

• US 20130223235A1
• Filed: 07/14/2010
• Published: 08/29/2013
• Est. Priority Date: 07/14/2010
• Status: Abandoned Application

• Current Assignee: Blackberry Limited
• Original Assignee: Blackberry Limited
• Inventors: Hu, Rose Qingyang, Cai, Zhijun, Bontu, Chandra Sekhar, Fong, Mo-Han, Yu, Yi, Song, Yi
• Application Number:
  US13/810,108
• Publication Number:
  US 20130223235A1
• Time in Patent Office: Days
• US Class Current: 370/242
• CPC Class Codes: H04W 36/04 Reselecting a cell layer in multi-layered cells
• CPC Class Codes: H04W 36/30 by measured or perceived connection quality data
• CPC Class Codes: H04W 36/302 due to low signal strength
• CPC Class Codes: H04W 48/20 Selecting an access point
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B

Abstract

A UE comprising a processor configured to perform cell selection based on range expansion according to a cell selection criteria that considers both a control channel quality and a data channel quality and further according to a cell ranking criterion. A fall back cell selection may be provided if a coverage hole is detected.

Claims

1. A UE comprising:

a processor configured to perform cell selection or reselection according to a received signal quality criterion that considers both a control channel signal quality and a data channel signal quality.

2. The UE of claim 1 wherein the processor is further configured to perform the cell selection or reselection according to a cell ranking criterion.

3. The UE of claim 1 wherein the processor is further configured to perform the cell selection or reselection to one of a low power access node, a pico access node, and a femto access node.

4. The UE of claim 1 wherein the received signal quality criterion further comprises a path loss based metric.

5. The UE of claim 4 wherein path loss is defined by a reference signal transmit power level minus a higher layered filtered reference signal received power.

6. The UE of claim 4 wherein the cell selection or reselection criterion fulfills the criteria defined as Srxlev>

0 AND Squal_D>

0 AND Squal_C>

0, wherein

Srxlev=Q_rxlevmeas−

(Q_rxlevmin+Q_{rxlevminoffset})−

Pcompensation

Squal_—

D=Q_qualmeasD−

(Q_qualminD+Q_{qualminoffsetD})

Squal_—

C=Q_qualmeasC−

(Q_qualminC+Q_{qualminoffsetC})

and

7. The UE of claim 1 wherein the cell ranking criterion comprises an Rs for a serving cell and an Rn for neighboring cells, and wherein the cell ranking criterion is defined as one of:

R_s=PL_meas,s+Q_Hyst—

PL

R_n=PL_meas,n−

Qoffset_PL 

 

(2)

or

R_s=Q_meas,s+Q_Hyst

R_n=Q_meas,n−

Qoffset1−

Qoffset 

 

(8)

where;

8. The UE of claim 7 wherein Qoffset1 and Qoffset are used in equation 8 when the UE experiences a certain channel quality condition while Qoffset1 is omitted when the UE experiences another channel quality condition.

9. The UE of claim 8, wherein the certain channel quality condition comprises when the channel quality received at the UE is above a threshold.

10. The UE of claim 8, wherein the another channel quality condition comprises when the channel quality received at the UE is below a threshold.

11. The UE of claim 8, wherein the certain channel quality condition comprises when the UE succeeds in decoding at least one of a control channel and a data channel with a given packet loss rate.

12. The UE of claim 8, wherein the another channel quality condition comprises when the UE fails to decode at least one of control channel and data channel with a given packet loss rate.

13. The UE of claim 1 wherein the cell selection or reselection criteria comprises a biased path loss metric.

14. The UE of claim 13 wherein the cell selection or reselection criterion fulfills the criteria defined as Srxlev>

0 AND Squal_D>

0 AND Squal_C>

0, wherein

Srxlev=Q_rxlevmeas−

(Q_rxlevmin+Q_{rxlevminoffset})−

Pcompensation

Squal_—

D=Q_qualmeasD−

(Q_qualminD+Q_{qualminoffsetD})

Squal_—

C=Q_qualmeasC−

(Q_qualminC+Q_{qualminoffsetC})

and

15. The UE of claim 13 wherein the cell ranking criterion comprises an Rs for a serving cell and an Rn for neighboring cells, and wherein the cell ranking criterion is defined as one of:

R_s=Q_meas,s+Q_Hyst+Qoffset1<sub>—

s</sub>

R_n=Q_meas,n+Qoffset1_n−

Qoffset 

 

(9)

where;

16. The UE of claim 15 wherein Qoffset1_n together with Qoffset are used by the UE to use path loss based cell selection or reselection when a coverage hole is not detected, and where Qoffset is used by the UE to use best power based cell selection or reselection as a fall back mechanism when a coverage hole is detected.

17. The UE of claim 16 wherein the coverage hole is detected when a packet error rate over a downlink transmission or an uplink transmission is above a predetermined packet error rate, and wherein the coverage hole is also detected when a received signal quality over the downlink transmission or the uplink transmission is above a predetermined received signal quality.

18. The UE of claim 17 wherein detection of the coverage hole is checked by measuring a success rate or failure rate over one or more downlink or uplink control channels.

19. The UE of claim 18 wherein the one or more downlink or uplink control channels are configured to assist detection of the coverage hole.

20. The UE of claim 15 wherein Qoffset1_n and Qoffset are used in Rn criteria (10) when the UE experiences a certain channel quality condition while Qoffset1 is omitted when the UE experiences another channel quality condition.

21. The UE of claim 20, wherein the certain channel quality condition comprises when the channel quality received at the UE is above a threshold.

22. The UE of claim 20, wherein the another channel quality condition comprises when the channel quality received at the UE is below a threshold.

23. The UE of claim 20, wherein the certain channel quality condition comprises when the UE succeeds in decoding at least one of a control channel and a data channel with a given packet loss rate.

24. The UE of claim 20, wherein the another channel quality condition comprises when the UE fails to decode at least one of a control channel and a data channel with a given packet loss rate.

25. A method comprising:

a user equipment (UE) performing one of cell selection or reselection according to a received signal quality criterion that considers both a control channel signal quality and a data channel signal quality.

26. The method of claim 25 further comprising:

performing the cell selection or reselection according to a cell ranking criterion.

27. The method of claim 25 further comprising:

performing the cell selection or reselection to one of a low power access node, a pico access node, and a femto access node.

28. The method of claim 25 wherein the received signal quality criterion further comprises a path loss based metric.

29. The method of claim 28 wherein path loss is defined by a reference signal transmit power level minus a higher layered filtered reference signal received power.

30. The method of claim 28 wherein the cell selection or reselection criterion fulfills the criteria defined as Srxlev>

0 AND Squal_D>

0 AND Squal_C>

0, wherein

Srxlev=Q_rxlevmeas−

(Q_rxlevmin+Q_{rxlevminoffset})−

Pcompensation

Squal_—

D=Q_qualmeasD−

(Q_qualminD+Q_{qualminoffsetD})

Squal_—

C=Q_qualmeasC−

(Q_qualminC+Q_{qualminoffsetC})

and

31. The method of claim 25 wherein the cell ranking criterion comprises an Rs for a serving cell and an Rn for neighboring cells, and wherein the cell ranking criterion is defined as one of:

R_s=PL_meas,s+Q_Hyst—

PL

R_n=PL_meas,n−

Qoffset_PL 

 

(2)

or

R_s=Q_meas,s+Q_Hyst

R_n=Q_meas,n−

Qoffset1−

Qoffset 

 

(8)

where;

32. The method of claim 31 wherein Qoffset1 and Qoffset are used in equation 8 when the UE experiences a certain channel quality condition while Qoffset1 is omitted when the UE experiences another channel quality condition.

33. The method of claim 32, wherein the certain channel quality condition comprises when the channel quality received at the UE is above a threshold.

34. The method of claim 32, wherein the another channel quality condition comprises when the channel quality received at the UE is below a threshold.

35. The method of claim 32, wherein the certain channel quality condition comprises when the UE succeeds in decoding at least one of a control channel and a data channel with a given packet loss rate.

36. The method of claim 32, wherein the another channel quality condition comprises when the UE fails to decode at least one of control channel and data channel with a given packet loss rate.

37. The method of claim 25 wherein the cell selection or reselection criteria comprises a biased path loss metric.

38. The method of claim 37 wherein the cell selection or reselection criterion fulfills the criteria defined as Srxlev>

0 AND Squal_D>

0 AND Squal_C>

0, wherein

Srxlev=Q_rxlevmeas−

(Q_rxlevmin+Q_{rxlevminoffset})−

Pcompensation

Squal_—

D=Q_qualmeasD−

(Q_qualminD+Q_{qualminoffsetD})

Squal_—

C=Q_qualmeasC−

(Q_qualminC+Q_{qualminoffsetC})

and

39. The method of claim 37 wherein the cell ranking criterion comprises an Rs for a serving cell and an Rn for neighboring cells, and wherein the cell ranking criterion is defined as one of:

R_s=Q_meas,s+Q_Hyst+Qoffset1<sub>—

s</sub>

R_n=Q_meas,n+Qoffset1_n−

Qoffset 

 

(9)

40. The method of claim 39 wherein Qoffset1_n together with Qoffset are used by the UE to use path loss based cell selection or reselection when a coverage hole is not detected, and where Qoffset is used by the UE to use best power based cell selection or reselection as a fall back mechanism when a coverage hole is detected.

41. The method of claim 40 wherein the coverage hole is detected when a packet error rate over a downlink transmission or an uplink transmission is above a predetermined packet error rate, and wherein the coverage hole is also detected when a received signal quality over the downlink transmission or the uplink transmission is above a predetermined received signal quality.

42. The method of claim 41 wherein detection of the coverage hole is checked by measuring a success rate or failure rate over one or more downlink or uplink control channels.

43. The UE of claim 42 wherein the one or more downlink or uplink control channels are configured to assist detection of the coverage hole.

44. The method of claim 39 wherein Qoffset1_n and Qoffset are used in Rn criteria (10) when the UE experiences a certain channel quality condition while Qoffset1 is omitted when the UE experiences another channel quality condition.

45. The method of claim 44, wherein the certain channel quality condition comprises when the channel quality received at the UE is above a threshold.

46. The method of claim 44, wherein the another channel quality condition comprises when the channel quality received at the UE is below a threshold.

47. The method of claim 44, wherein the certain channel quality condition comprises when the UE succeeds in decoding at least one of a control channel and a data channel with a given packet loss rate.

48. The method of claim 44, wherein the another channel quality condition comprises when the UE fails to decode at least one of a control channel and a data channel with a given packet loss rate.