Default radio link monitoring reference signal (RLM-RS) determination procedure in new radio (NR)
Certain aspects of the present disclosure relate to methods and apparatus for radio link monitoring reference signal (RLM-RS) determination using communications systems operating according to new radio (NR) technologies. For example, a method for wireless communications from a UE generally includes determining resources to monitor for radio link monitoring (RLM) prior to being configured with resources to monitor for RLM after establishing a radio resource control (RRC) connection with a network, and performing RLM based on the determined resources.
1. A method of wireless communication, the method comprising:
establishing, by a user equipment (UE), a radio resource control (RRC) connection with a network;
determining, by the UE, while the UE is in RRC-CONNECTED mode and prior to being configured by the network with radio link monitoring reference signal (RLM-RS) resources, default RLM-RS resources based on synchronization signal (SS) block (SSB) reference signals or channel state information references signals (CSI-RS); and
performing, by the UE, RLM based on the default RLM-RS resources.
2. The method of claim 1 , wherein determining the default RLM-RS resources comprises selecting one among the SSB reference signals and the CSI-RS as the default RLM-RS.
3. The method of claim 1 , wherein:
determining the default RLM-RS resources is based on one or more control resource sets (CORESETs) and search spaces.
4. The method of claim 3 , wherein determining the default RLM-RS resources is based on reference signals associated with spatial quasi-colocation (QCL) parameters in a transmission configuration indication (TCI) state of the one or more configured CORESETs.
5. The method of claim 4 , further comprising receiving the QCL parameters in the TCI state of the one or more configured CORESETs from the network.
6. The method of claim 4 , wherein the reference signals associated with spatial QCL parameters in the TCI state of the one or more configured CORESETs correspond to the SSB reference signals or the CSI-RS.
7. The method of claim 4 , wherein determining the default RLM-RS resources comprises determining the SSB reference signals or the CSI-RS associated with the spatial QCL parameters in the TCI states of the one or more configured CORESETs as the default RLM-RSs.
8. The method of claim 1 , further comprising:
utilizing, by the UE, a first set of parameters for RLM and Radio Link Failure (RLF) process prior to being configured with RLM-RS resources after establishing a RRC connection with the network; and
updating, by the UE, one or more of the first set of parameters for RLM and RLF process after establishing a radio resource control (RRC) connection with the network.
9. The method of claim 8 , wherein updating the one or more of the first parameters comprises increasing or decreasing the one or more of the first parameters by a fixed amount.
10. An apparatus for wireless communication, comprising:
means for establishing a radio resource control (RRC) connection with a network;
means for determining, while the apparatus is in RRC-CONNECTED mode and prior to being configured by the network with radio link monitoring reference signal (RLM-RS) resources, default RLM-RS resources based on synchronization signal (SS) block (SSB) reference signals or channel state information references signals (CSI-RS); and
means for performing RLM based on the default RLM-RS resources.
11. The apparatus of claim 10 , wherein the means for determining the default RLM-RS resources comprises means for selecting one among the SSB reference signals and the CSI-RS as the default RLM-RS.
12. The apparatus of claim 10 , wherein:
the means for determining the default RLM-RS resources is based on one or more control resource sets (CORESETs) and search spaces.
13. The apparatus of claim 12 , wherein the means for determining the default RLM-RS resources is based on reference signals associated with spatial quasi-colocation (QCL) parameters in a transmission configuration indication (TCI) state of the one or more configured CORESETs.
14. The apparatus of claim 13 , wherein the reference signals associated with spatial QCL parameters in the TCI state of the one or more configured CORESETs correspond to the SSB reference signals or the CSI-RS.
15. The apparatus of claim 13 , wherein the means for determining the default RLM-RS resources comprises means for determining the SSB reference signals or the CSI-RS associated with the spatial QCL parameters in the TCI states of the one or more configured CORESETs as the default RLM-RSs.
16. An apparatus for wireless communication, comprising:
at least one processor;
a memory coupled with the at least one processor; and
instructions stored in the memory and executable by the at least one processor to cause the apparatus to:
establish a radio resource control (RRC) connection with a network;
determine, while the apparatus is in RRC-CONNECTED mode and prior to being configured by the network with radio link monitoring reference signal (RLM-RS) resources, default RLM-RS resources based on synchronization signal (SS) block (SSB) reference signals or channel state information references signals (CSI-RS); and
perform RLM based on the default RLM-RS resources.
17. The apparatus of claim 16 , wherein the instructions are further executable by the at least one processor to cause the apparatus to select one among the SSB reference signals and the CSI-RS as the default RLM-RS.
18. The apparatus of claim 16 , wherein the instructions are further executable by the at least one processor to cause the apparatus to determine the default RLM-RS resources based on one or more control resource sets (CORESETs) and search spaces.
19. The apparatus of claim 18 , wherein the instructions are further executable by the at least one processor to cause the apparatus to determine the default RLM-RS resources based on reference signals associated with spatial quasi-colocation (QCL) parameters in a transmission configuration indication (TCI) state of the one or more configured CORESETs.
20. The apparatus of claim 19 , wherein the instructions are further executable by the at least one processor to cause the apparatus to receive the QCL parameters in the TCI state of the one or more configured CORESETs from the network.
21. The apparatus of claim 19 , wherein the reference signals associated with spatial QCL parameters in the TCI state of the one or more configured CORESETs correspond to the SSB reference signals or the CSI-RS.
22. The apparatus of claim 19 , wherein the instructions are further executable by the at least one processor to cause the apparatus to determine the SSB reference signals or the CSI-RS associated with the spatial QCL parameters in the TCI states of the one or more configured CORESETs as the default RLM-RSs.