uration is included in SIB1. Furthermore, the SCS for SIB1, Msg.2/Msg.4 for initial access, and broadcast SI-messages is included in the MIB. For NR-U, these SCS configura- tion schemes can be reused directly. In licensed bands, NR supports dynamic and semi- statically configured slot configuration. The semi-static DL/UL assignment is done via cell- specific and UE-specific RRC configuration. With the cell-specific configuration, the UE is Operation in Unlicensed and Shared Spectrum Fixed frame period Fixed frame period LAA frame LAA frame Idle period Idle period Fixed frame period Fixed frame period Content Content Content Content Slot 0 Slot M-1 Slot 0 Slot M-1 M contention M contention slots slots Figure 8.21 Illustration of timing relation for FBE [24,25]. allocated flexible resources that can be assigned to downlink or uplink using UE-specific configuration or dynamic signaling. The UE-specific RRC signaling or dynamic signaling includes per-slot-basis indication that can override the unknown allocation in the cell- specific configuration. Resources in the slot configuration that are without downlink/uplink indication are considered flexible resources. Frame-based equipment (FBE) 10 is a channel access mechanism wherein the transmit/ receive frame structure has a periodic timing with a periodicity known as the fixed frame period (FFP), which is between 1 and 10 ms. The transmitting device performs a single-shot LBT before starting transmission in a channel at the beginning of an FFP, and the channel occupancy time (COT) associated with a successful LBT (see the example shown in Fig. 8.21). In addition to the load-based equipment (LBE) operation mode, NR-U can also support the FBE operation mode for use cases in which other LBE-based networks (e.g., Wi-Fi, LTE-based LAA) are excluded such as in a factory or private NR-U network. In comparison to the LBE mode, the FBE operation mode can achieve higher spectrum utiliza- tion in such scenarios considering much simpler LBT process. The necessity of signaling to i