 an RNA update procedure is performed. The UE usually searches for higher priority PLMNs at regular time intervals and continues to search for a more suitable cell, if another PLMN has been selected by NAS. If the UE loses the coverage of the registered PLMN, either a new PLMN is automatically selected (automatic mode), or the user is notified of the available PLMNs SO that a manual selection can be performed (manual mode). The purpose of camping on a cell in RRC_IDLE or RRC_INACTIVE state is to enable the UE to receive SI from the PLMN, when registered. If the network needs to send a message or deliver data to the registered UE, it knows the set of tracking areas (in RRC_IDLE state) or RNA (in RRC_INACTIVE state) in which the UE is camped. The network can then send a paging message to the UE on the control channels of all cells in the corresponding set of (tracking) areas. It further enables the UE to receive ETWS and CMAS notifications. During the PLMN selection, the UE scans all RF channels in the NR bands according to its New Radio Access Layer 2/3 Aspects and System Operation 247 capabilities to find available PLMNs. On each carrier, the UE searches for the strongest cell and acquires the SI in order to find which PLMN(s) the cell belongs to. If the UE can detect one or several PLMN identities in the strongest cell, each detected PLMN is reported to the NAS as a high-quality PLMN provided that the measured reference signal received power value is greater than or equal to 110 dBm [12]. As we mentioned earlier, the PLMN selection in NR is based on the 3GPP PLMN selection, and that is, cell selection is required upon transition from RM-DEREGISTERED to RM-REGISTERED, from CM-IDLE to CM-CONNECTED, and from CM-CONNECTED to CM-IDLE based on the following principles [8]: The UE NAS layer identifies a PLMN and equivalent PLMNs. Cell selection is always based on cell-defining SSBs (CD-SSBs)9 located on the chronization raster. The UE searches the designated NR frequency bands and for each carrier frequency identifies 