 Access Network (O-RAN) Systems Architecture and Design Table 2-2 5G Numerology. Cyclic prefix Af = 15 KHz X 2u Normal 15 KHz Normal 30 KHz Normal, extended 60 KHz Normal 120 KHz Normal 240 KHz Normal 480 KHz 1 msec subframe Slot (14 Symbols) 15KHz 30KHz Slot (14 Symbols) 60KHz Slot (14 S) 120KHz (14 S) FIGURE 2-28 Frame structure. 1 symbol 14 Symbols (0521) Biocie FIGURE 2-29 Resource block definition. Chapter 2 System components, requirements, and interfaces 73 Physical Downlink Shared Channel (PDSCH)-this carries bulk data in time and frequency dimensions, sharing the channel capacity to different users. Physical Broadcast Channel (PBCH)-this channel is used to communicate the MIB that is used as the first anchor for channel discovery from UE to gNB. Uplink: Physical Uplink Control Channel (PUCCH)-used to carry uplink control data, or at least the portion of the uplink control data that is not transmitted through the PUSCH. Physical Uplink Shared Channel (PUSCH)-counter to the PDSCH, this channel is used for bulk data transfer from UE to gNB. Physical Random Access Channel (PRACH)-used for transmission of a channel access preamble (sequence) to initiate connectivity from UE to gNB. Radio Network Temporary Identifier RNTI stands for Radio Network Temporary Identifier and is used to identify a connected UE or group of UEs (paging) a radio channel or similar. It is the identifier that is used to identify either a UE within a cell (typically), a specific radio channel or a group of UEs (for paging, power control or system information transmission) by the gNB. The RNTI is used by the Physical Layer to identify which channels it needs to decode. Numerology A frame is defined as a 10-ms interval and is divided into subframes of 1 ms each. Air inter- face processing (including scheduling) is done on a group of 14 OFDMA symbols, which is defined as a slot. The physical time duration of a slot is defined by the parameter u which defines the SCS, per Table 2-2. For shared channel, 15, 30, and 60-KHz SCS is used in <6 GHz