Devices for radio link monitoring
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.
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 primary cell (PCell);
monitor the radio link quality for a secondary cell that is different from the PCell and is a timing reference for a time alignment (TA) group that does not include the PCell;
determine whether a physical layer problem is detected based on the radio link quality for the secondary cell; and based on a detection of a physical layer problem for the secondary cell:
stop a time alignment timer (TAT) corresponding to the TA group or consider the time alignment timer (TAT) corresponding to the TA group as expired.
2. The UE of claim 1 , wherein based on a detection of the physical layer problem, the instructions are further executable to stop an ongoing random access procedure on the secondary cell.
3. The UE of claim 1 , wherein the instructions executable to determine whether a physical layer problem is detected comprise instructions executable to determine whether a number of consecutive out-of-sync indications for the PCell are received, while in a radio resource control (RRC) connected state, from the physical layer.
4. A method for radio link monitoring on a user equipment (UE), comprising:
monitoring a radio link quality for a primary cell (PCell);
monitoring the radio link quality for a secondary cell that is different from the PCell and is a timing reference for a time alignment (TA) group that does not include the PCell;
determining whether a physical layer problem for the secondary cell is detected based on the radio link quality; and based on a detection of a physical layer problem for the secondary cell:
stopping a time alignment timer (TAT) corresponding to the TA group or considering the time alignment timer (TAT) corresponding to the TA group as expired.
5. The method of claim 4 , wherein based on a detection of the physical layer problem, the method further comprises stopping an ongoing random access procedure on the secondary cell.
6. A non-transitory, tangible computer-readable medium for radio link monitoring, comprising executable instructions for:
monitoring a radio link quality for a primary cell (PCell);
monitoring the radio link quality for a secondary cell that is different from the PCell and is a timing reference for a time alignment (TA) group that does not include the PCell;
determining whether a physical layer problem is detected based on the radio link quality for the secondary cell; and based on a detection of a physical layer problem for the secondary cell:
stopping a time alignment timer (TAT) corresponding to the TA group or considering the time alignment timer (TAT) corresponding to the TA group as expired.
7. The computer-readable medium of claim 6 , wherein based on a detection of the physical layer problem, the executable instructions are further executable to stop an ongoing random access procedure on the secondary cell.