Method for NR Radio Link Monitoring (RLM) and Evaluation Period Determination

Abstract

Methods are proposed to define UE behavior for performing synchronization signal block (SSB) based radio link monitoring (RLM) and channel state information reference signal (CSI-RS) based RLM. In a first novel aspect, if CSI-RS based RLM-RS is not QCLed to any CORESET, then UE determines that CSI-RS RLM configuration is error and does not perform RLM accordingly. In a second novel aspect, SSB for RLM and RLM CSI-RS resources are configured with different numerologies. UE perform SSB based RLM and CSI-RS based RLM based on whether the SSB and CSI-RS resources are TDMed configured by the network. In a third novel aspect, when multiple SMTC configurations are configured to UE, UE determines an SMTC period and whether SMTC and RLM-RS are overlapped for the purpose of RLM evaluation period determination.

What is claimed is: 
     
         1 . A method comprising:
 receiving core resource set (CORESET) configuration by a user equipment (UE) in a new radio (NR) network, wherein the CORESET configuration comprises one or more CORESETs for the UE;   receiving radio link monitoring (RLM) configuration comprising resource information of a plurality of channel state information reference signals (CSI-RSs) for RLM;   determining whether a configured CSI-RS for RLM is Quasi-Co-Located (QCLed) to any CORESET according to the resource information of the CSI-RSs; and   performing RLM measurements using the configured CSI-RS for RLM only when the configured CSI-RS for RLM is QCLed to at least one CORESET.   
     
     
         2 . The method of  claim 1 , wherein the determining of whether the configured CSI-RS for RLM is QCLed to any CORESET is according to time, frequency resource location, and QCL information for CSI-RS based RLM included in the resource information. 
     
     
         3 . The method of  claim 1 , wherein the determining of whether the configured CSI-RS for RLM is QCLed to any CORESET comprises determining whether receiving a CORESET with reference to at least one of Doppler shift, Doppler spread, average delay and delay spread of the configured CSI-RS for RLM in a first frequency range (FR1) as defined in a 3rd-Generation Partnership Project (3GPP) specification. 
     
     
         4 . The method of  claim 3 , wherein the FR1 as defined in a 3rd-Generation Partnership Project (3GPP) specification includes sub7 GHz band. 
     
     
         5 . The method of  claim 1 , wherein the determining of whether the configured CSI-RS for RLM is QCLed to any CORESET comprises determining whether receiving a CORESET with reference to at least one of Doppler shift, Doppler spread, average delay, delay spread and spatial RX parameters of the configured CSI-RS for RLM in a second frequency range (FR2) as defined in a 3rd-Generation Partnership Project (3GPP) specification. 
     
     
         6 . The method of  claim 5 , wherein the FR2 as defined in a 3rd-Generation Partnership Project (3GPP) specification includes millimeter Wave band. 
     
     
         7 . A method, comprising:
 receiving synchronization signal block (SSB) configuration for radio link monitoring (RLM) by a user equipment (UE) in a new radio (NR) network, wherein the SSB occupies a first OFDM symbol having a first numerology;   receiving channel state information reference signal (CSI-RS) configuration for RLM by the UE, wherein the configured CSI-RS resource is allocated over a second OFDM symbol having a second numerology;   determining whether the SSB and the configured CSI-RS resource are Time Division Multiplexed (TDMed) responsive to the first numerology and the second numerology being different; and   performing SSB based RLM and CSI-RS based RLM using the SSB and CSI-RS configuration for RLM based on whether the SSB and the configured CSI-RS resource are TDMed.   
     
     
         8 . The method of  claim 7 , wherein the first numerology and the second numerology being different includes the first numerology and the second numerology having different subcarrier spacing (SCS) values. 
     
     
         9 . The method of  claim 7 , wherein the first numerology and the second numerology being different includes the first numerology and the second numerology having different cyclic-shift prefix (CP) lengths. 
     
     
         10 . The method of  claim 7 , wherein the performing SSB based RLM and CSI-RS based RLM based on whether the SSB and the configured CSI-RS resource are TDMed includes performing SSB based RLM and CSI-RS based RLM only when the SSB and the configured CSI-RS resource are TDMed. 
     
     
         11 . The method of  claim 7 , wherein the performing SSB based RLM and CSI-RS based RLM is further based on whether the UE supports simultaneous reception over different numerologies. 
     
     
         12 . The method of  claim 11 , wherein the performing SSB based RLM and CSI-RS based RLM based on whether the UE supports simultaneous reception over different numerologies includes performing SSB based RLM and CSI-RS based RLM only when the UE does NOT support simultaneous reception over different numerologies. 
     
     
         13 . The method of  claim 7 , wherein the determining of whether the SSB and the configured CSI-RS resource are TDMed includes determining whether the SSB and the configured CSI-RS resource are completely not overlapped in time domain. 
     
     
         14 . A method, comprising:
 receiving synchronization signal block (SSB) measurement timing configuration (SMTC) for radio link monitoring (RLM) by a user equipment (UE) in a new radio (NR) network;   determining an RLM evaluation period according to the SMTC configuration for RLM based at least on an SMTC periodicity; and   performing RLM using the determined RLM evaluation period.   
     
     
         15 . The method of  claim 14 , wherein the SMTC configuration comprises an SMTC periodicity, an SMTC window duration, and a timing offset. 
     
     
         16 . The method of  claim 15 , wherein a first smtc 1  and a second smtc 2  are configured by the network, and wherein the RLM evaluation period is determined based on the shortest SMTC periodicity. 
     
     
         17 . The method of  claim 16 , wherein the shortest SMTC periodicity is the smtc 2  periodicity. 
     
     
         18 . The method of  claim 15 , wherein a first smtc 1  and a second smtc 2  are configured by the network, and wherein the RLM evaluation period is determined based on the smtc 2  periodicity. 
     
     
         19 . The method of  claim 14 , wherein the determining the RLM evaluation period is further based on an RLM evaluation scaling factor for channel state information reference signal (CSI-RS) based RLM, and the RLM evaluation scaling factor is associated with whether CSI-RS resources and SMTC window durations are overlapped. 
     
     
         20 . The method of  claim 19 , wherein a CSI-RS resource and an SMTC window duration are considered overlapped as long as the CSI-RS resource is allocated within the SMTC window duration.