 carrier frequency: - 4 SSB blocks maximum for a frequency lower than 3GHz; - 8 SSB blocks maximum for a lower frequency between 3 GHz and 7.125 GHz; - 64 SSB blocks maximum for a frequency in the FR2 band. During the cell search procedure, the mobile searches for the initial BWP partition. The initial BWP partition is a frequency sub-band on which the mobile reads the minimum system information RMSI (Remaining Minimum System Information). MIB information is carried over the BCCH channel, and SIB1 information is carried over the PDSCH control channel. The SIB1 information allows the mobile to learn about the parameters of random access to the cell. NG-RAN and 5G-NR The physical downlink control channel (PDCCH) carries Downlink Control Information (DCI). The DCI message indicates the downlink resources for PDSCH. The mobile searches DCI information in a common search space called the Type0-PDCCH search space. According to the kssb (ssb-subcarrierOffset) value transmitted on the MIB message, the mobile knows whether Type0-PDCCH is present or not in the BWP: - in the case of the FR1 band (Frequency Range 1 ranging from 450 MHz to 7.125 GHz), if kssb 23, then the BWP partitioning contains a Type0-PDCCH on which the mobile reads the SIB1 information; - in the case of the FR2 band (Frequency Range 2 ranging from 24.250 MHz to 52.6 GHz), if kssb 11, then the BWP partitioning contains a Type0-PDCCH on which the mobile reads the SIB 1 information. The SIB1 information carries: - the radio resources of the CORESET control area (COntrol REsource SET) from the PDCCH-ConfigSIB1 message (in addition to the common search area); - measurement information for the selection or re-selection of cells; - the configuration of the random access request. Once synchronized on an SSB, the mobile transmits a random access request to establish a bearer connection. The procedure is described by the exchange of the following four messages (Figure 3.7). The MAC entity of the mobile chooses a random preamble from the list corresponding to the s