16.9.4.1 General

When a UE is inside NG-RAN coverage, NR sidelink communication and/or V2X sidelink communication can be configured and controlled by NG-RAN via dedicated signalling or system information:

• The UE should support and be authorized to perform NR sidelink communication and/or V2X sidelink communication in NG-RAN;
• If configured, the UE performs V2X sidelink communication as specified in TS 36.300 [2] unless otherwise specified, with the restriction that the dynamic scheduling for V2X sidelink communication (i.e. based on SL-V-RNTI) is not supported;
• NG-RAN can provide the UE with intra-carrier sidelink configuration, inter-carrier sidelink configuration and anchor carrier(s) which provide sidelink configuration via a Uu carrier for NR sidelink communication and/or V2X sidelink communication;
• When the UE cannot simultaneously perform both NR sidelink transmission and NR uplink transmission in time domain, prioritization between both transmissions is done based on their priorities and thresholds configured by the NG-RAN or pre-configured. When the UE cannot simultaneously perform both V2X sidelink transmission and NR uplink transmission in time domain, prioritization between both transmissions is done based on the priorities (i.e. PPPP) of V2X sidelink communication and a threshold configured by the NG-RAN or pre-configured.

When a UE is outside NG-RAN coverage, SL DRB configuration(s) are preconfigured to the UE for NR sidelink communication. If UE changes the RRC state but has not received the SL DRB configuration(s) for the new RRC state, UE continues using the configuration obtained in the previous RRC state to perform sidelink data transmissions and receptions until the configuration for the new RRC state is received.