METHOD AND APPARATUS FOR RADIO LINK FAILURE RECOVERY

• US 20110039546A1
• Filed: 08/17/2009
• Published: 02/17/2011
• Est. Priority Date: 08/17/2009
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: KUCHIBHOTLA, Ravi, NARASIMHA, Murali
• Granted Patent: US 8,774,135 B2
• Time in Patent Office: Days
• US Class Current: 455/423
• CPC Class Codes: H04W 36/0058 Transmission of hand-off measurement information, e.g. measurement reports
• CPC Class Codes: H04W 36/0088 Scheduling hand-off measurements
• CPC Class Codes: H04W 36/30 by measured or perceived connection quality data
• CPC Class Codes: H04W 36/305 Handover due to radio link failure control signalling for hand-off failure H04W36/0079
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B

Abstract

A method (300) and apparatus (200) for radio link failure recovery is disclosed. The method may include detecting (320) the presence of an intra-frequency neighbor base station (145) of a serving base station (135). The method may include determining (330) that a radio link parameter of an inter-frequency neighbor base station is better than a threshold. The method may include acquiring (350) system information of the inter-frequency neighbor base station if the intra-frequency neighbor base station is present and if the radio link parameter of the inter-frequency neighbor base station is better than the threshold.

Claims

1. A method in a mobile station, the method comprising:

detecting a presence of an intra-frequency neighbor base station of a serving base station;

determining that a radio link parameter of an inter-frequency neighbor base station is better than a threshold; and

acquiring system information of the inter-frequency neighbor base station if the intra-frequency neighbor base station is present and if the radio link parameter of the inter-frequency neighbor base station is better than the threshold.

2. The method according to claim 1, wherein the radio link parameter comprises a reference signal received power parameter.

3. The method according to claim 1,

wherein detecting the presence of the intra-frequency neighbor base station comprises determining that a radio link parameter of the intra-frequency neighbor base station is better than another threshold, and

wherein acquiring the system information comprises acquiring the system information of the inter-frequency neighbor base station if the radio link parameter of the inter-frequency neighbor base station is better than the threshold and if the radio link parameter of the intra-frequency neighbor base station is better than the another threshold.

4. The method according to claim 3 further comprising sending a measurement report to the serving base station, the measurement report indicating that the radio link parameter of the inter-frequency neighbor base station is better than the threshold.

5. The method according to claim 3 further comprising sending a measurement report to the serving base station, the measurement report indicating that the radio link parameter of the intra-frequency neighbor base station is better than the another threshold.

6. The method according to claim 1, wherein the radio link parameter of the inter-frequency neighbor base station is computed from at least one of a plurality of measured parameters, the plurality of measured parameters including a measured parameter of the inter-frequency base station.

7. The method according to claim 1 further comprising determining that the mobile station is not allowed to access the intra-frequency neighbor base station,

wherein acquiring the system information comprises acquiring the system information of the inter-frequency neighbor base station if the intra-frequency neighbor base station is present, if the radio link parameter of the inter-frequency neighbor base station is better than the threshold, and if the mobile station is not allowed to access the intra-frequency neighbor base station.

8. The method according to claim 1 further comprising receiving an instruction from the serving base station to acquire the system information of the inter-frequency neighbor base station.

9. The method according to claim 1 further comprising receiving gap assignments for system information acquisition if the radio link parameter of the inter-frequency neighbor base station is better than the threshold.

10. The method according to claim 1 further comprising:

determining radio link failure on the serving base station after acquiring the system information; and

performing reestablishment on the inter-frequency neighbor base station using the acquired system information in response to determining radio link failure on the serving base station.

11. The method according to claim 10 further comprising receiving buffered data after performing reestablishment.

12. A method in a base station, the method comprising:

receiving a measurement report from a mobile station indicating presence of a cell operating on a same frequency as the base station;

identifying an alternate base station on a different frequency in response to receiving the measurement report; and

instructing the mobile station to acquire system information of the alternate base station.

13. The method according to claim 12 further comprising preparing the alternate base station for reestablishment for the mobile station.

14. The method according to claim 12 further comprising assigning gaps for the mobile station to acquire system information from the alternate base station.

15. An apparatus comprising:

a wireless communication device housing;

a transceiver coupled to the wireless communication device housing;

a controller coupled to the transceiver, the controller configured to control operations of the apparatus;

an intra-frequency neighbor base station detection module coupled to the controller, the intra-frequency neighbor base station detection module configured to detect a presence of an intra-frequency neighbor base station of a serving base station;

an inter-frequency neighbor base station parameter determination module coupled to the controller, the inter-frequency neighbor base station parameter determination module configured to determine that a radio link parameter of an inter-frequency neighbor base station is better than a threshold; and

a system information acquisition module coupled to the controller, the system information acquisition module configured to acquire system information of the inter-frequency neighbor base station if the intra-frequency neighbor base station is present and if the radio link parameter of the inter-frequency neighbor base station is better than the threshold.

16. The apparatus according to claim 15,

wherein the intra-frequency neighbor base station detection module is configured to determine that a radio link parameter of the intra-frequency neighbor base station is better than another threshold, and

wherein the system information acquisition module is configured to acquire the system information of the inter-frequency neighbor base station if the radio link parameter of the inter-frequency neighbor base station is better than the threshold and if the radio link parameter of the intra-frequency neighbor base station is better than the another threshold.

17. The apparatus according to claim 16, wherein the controller is configured to send, via the transceiver, a measurement report to the serving base station, the measurement report indicating that the radio link parameter of the inter-frequency neighbor base station is better than the threshold and indicating that the radio link parameter of the intra-frequency neighbor base station is better than the another threshold.

18. The apparatus according to claim 15, wherein the controller is configured to determine that the intra-frequency neighbor base station is a home base station.

19. The apparatus according to claim 15,

wherein the controller is configured to determine that a mobile station is not allowed to access the intra-frequency neighbor base station, and

wherein the system information acquisition module is configured to acquire the system information of the inter-frequency neighbor base station if the intra-frequency neighbor base station is present, if the radio link parameter of the inter-frequency neighbor base station is better than the threshold, and if the mobile station is not allowed to access the intra-frequency neighbor base station.

20. The apparatus according to claim 15, wherein the controller is configured to determine radio link failure on the serving base station after acquiring the system information and configured to perform reestablishment on the inter-frequency neighbor base station using the acquired system information in response to determining radio link failure on the serving base station.