DEVICES FOR RADIO LINK MONITORING

• US 20130083675A1
• Filed: 09/29/2011
• Published: 04/04/2013
• Est. Priority Date: 09/29/2011
• Status: Active Grant

• Current Assignee: Guangdong OPPO Mobile Telecommunications Corporation Limited
• Original Assignee: Sharp Laboratories of America Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Yamada, Shohei
• Granted Patent: US 9,319,909 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic

Abstract

A user equipment (UE) configured for radio link monitoring is described. The UE includes a processor and instructions stored in memory that is in electronic communication with the processor. The UE monitors a radio link quality for a secondary cell (SCell). The UE also determines whether a physical layer problem is detected based on the radio link quality. If a physical layer problem is detected, the UE stops a time alignment timer (TAT) of the SCell or sets the time alignment timer (TAT) of the SCell as expired.

Claims

1. A user equipment (UE) configured for radio link monitoring, comprising:

a processor;

memory in electronic communication with the processor;

instructions stored in the memory, the instructions being executable to;

monitor a radio link quality for a secondary cell (SCell);

determine whether a physical layer problem is detected based on the radio link quality; and

if a physical layer problem is

detected, then;

stop a time alignment timer (TAT) of the SCell or set the time alignment timer (TAT) of the SCell as expired.

2. The UE of claim 1, wherein if the physical layer problem is indicated, the instructions are further executable to stop a random access procedure on the SCell.

3. The UE of claim 1, wherein if the physical layer problem is indicated, the instructions are further executable to avoid a random access procedure for the SCell.

4. The UE of claim 1, wherein an sCellDeactivationTimer for the SCell is set to infinity.

5. The UE of claim 1, wherein the SCell comprises a timing reference for a time alignment (TA) group that does not include a primary cell (PCell).

6. The UE of claim 1, wherein if the physical layer problem is indicated, the instructions are further executable to do at least one of the group consisting of:

avoid starting a time alignment timer (TAT) when a time alignment (TA) command is received, avoid restarting a TAT when the TA command is received, ignore the TA command, ignore a received downlink control channel (PDCCH) order to initiate random access, avoid monitoring a PDCCH for the SCell, stop sounding reference signal (SRS) transmissions in a corresponding TA group, flush hybrid automatic repeat request (HARQ) buffers for the corresponding TA group, avoid performing any uplink transmission on the SCell and keep reporting feedback information for the SCell.

7. A method for radio link monitoring on a user equipment (UE), comprising:

monitoring a radio link quality for a secondary cell (SCell);

determining whether a physical layer problem is detected based on the radio link quality; and

if a physical layer problem is detected, then;

stopping a time alignment timer (TAT) of the SCell or setting the time alignment timer (TAT) of the SCell as expired.

8. The method of claim 7, wherein if the physical layer problem is indicated, the method further comprises stopping a random access procedure on the SCell.

9. The method of claim 7, wherein if the physical layer problem is indicated, the method further comprises avoiding a random access procedure for the SCell.

10. The method of claim 7, wherein an sCellDeactivationTimer for the SCell is set to infinity.

11. The method of claim 7, wherein the SCell comprises a timing reference for a time alignment (TA) group that does not include a primary cell (PCell).

12. The method of claim 7, wherein if the physical layer problem is indicated, the method further comprises at least one of the group consisting of:

avoiding starting a time alignment timer (TAT) when a time alignment (TA) command is received, avoiding restarting a TAT when the TA command is received, ignoring the TA command, ignoring a received downlink control channel (PDCCH) order to initiate random access, avoiding monitoring a PDCCH for the SCell, stopping sounding reference signal (SRS) transmissions in a corresponding TA group, flushing hybrid automatic repeat request (HARQ) buffers for the corresponding TA group, avoiding performing any uplink transmission on the SCell and keeping reporting feedback information for the SCell.

13. A non-transitory, tangible computer-readable medium for radio link monitoring, comprising executable instructions for:

monitoring a radio link quality for a secondary cell (SCell);

determining whether a physical layer problem is detected based on the radio link quality; and

if a physical layer problem is detected, then;

stopping a time alignment timer (TAT) of the SCell or setting the time alignment timer (TAT) of the SCell as expired.

14. The computer-readable medium of claim 13, wherein if the physical layer problem is indicated, the computer-readable medium further comprises executable instructions for stopping a random access procedure on the SCell.

15. The computer-readable medium of claim 13, wherein if the physical layer problem is indicated, the computer-readable medium further comprises executable instructions for avoiding a random access procedure for the SCell.

16. The computer-readable medium of claim 13, wherein an sCellDeactivationTimer for the SCell is set to infinity.