5.35-5.47 GHz 5.47-5.59 GHz 5.59-5.65 GHz 5.65-5.725 GHz 5.725-5.825 GHz 5.82-5.85 GHz 5.85-5.925 GHz China Indoor Indoor DFS/ Indoor/outdoor DFS/TPC (325 MHz) Europe Indoor LBT Indoor/outdoor Indoor/outdoor (455 MHz) DFS/TPC L DFS/TPC LBT Japan Indoor LBT Indoor/outdoor Indoor/outdoor (455 MHz) DFS/TPC LBT DFS/TPC LBT Korea Indoor Indoor/outdoor Indoor/outdoor Indoor/outdoor (480 MHz) DFS/TPC DFS/TPC The United Indoor/outdoor Indoor/outdoor Indoor/outdoor Indoor/outdoor States DFS/TPC DFS/TPC (580 MHz) 850 Chapter 8 considered for unlicensed use. The FCC has some regulations regarding transmission band- width, maximum transmit power, out-of-band emission, power spectrum density, transmit power control (TPC), and DFS for each unlicensed band. For example, the maximum trans- mit power is 24 dBm in the UNII-1 and UNII-2A bands, and 30 dBm in the UNII-2C and UNII-3 bands. In addition to the maximum transmit power, TPC may further limit the out- put power of a transmitter to minimize interference to users of other wireless technologies. In fact, TPC is required for both the UNII-2A and UNII-2C bands. The DFS is used for unlicensed devices to detect radar signals and to change their operating channels whenever radar activity is detected. The DFS should be adopted in the UNII-2A and UNII-2C bands to protect radar signals. Unlike LTE-based LAA/eLAA that only provide support for the 5 GHz unlicensed band, the NR is required to cover a wide range of unlicensed and shared licensed frequency bands, where regulatory and inter-RAT coexistence requirements may differ for each band. This includes 3.5 GHz band that has been designated as a shared band in the United States as well as the 5 and 60 GHz bands that are unlicensed bands. Moreover, the system design needs to consider the vastly different wireless channel characteristics for the lower carrier frequency bands such as sub-6 GHz as well as higher carrier frequency bands such as 60 GHz [26]. 5G networks are expected to operate over a wide range of licensed and unlicensed fr