In the fifth generation wireless communication system, node B (gNB) or base station in cell broadcast Synchronization Signal and physical broadcast channel (PBCH) block (SSB) consists of primary and secondary synchronization signals (PSS, SSS) and system information. System information includes common parameters needed to communicate in cell. In the fifth generation wireless communication system (also referred as next generation radio or NR), System Information (SI) is divided into the master information block (MIB) and a number of system information blocks (SIBs) where:

the MIB is always transmitted on the BCH with a periodicity of 80 ms and repetitions made within 80 ms and it includes parameters that are needed to acquire SIB1 from the cell.

the SIB1 is transmitted on the DL-SCH with a periodicity of 160 ms and variable transmission repetition. The default transmission repetition periodicity of SIB1 is 20 ms but the actual transmission repetition periodicity is up to network implementation. The scheduling information in the SIB 1 includes mapping between the SIBs and the SI messages, periodicity of each SI message and SI window length. The scheduling information in the SIB 1 includes an indicator for each SI message, which indicates whether the concerned SI message is being broadcasted or not. If at least one SI message is not being broadcasted, SIB1 may include random access resources (physical random access channel (PRACH) preamble(s) and PRACH resource(s)) for requesting gNB to broadcast one or more SI message(s).