lution facil- itates deployment when 5G (or LTE) inside a building has utilized a distributed antenna system. In that case, connecting unlicensed operation to the distributed antenna system in the carrier aggregation scenario is not possible (as lower power would be distributed for the whole antenna system, and one would need to listen to the whole area covered by the antenna system for LBT operation). The standalone operation allows one to use 5G-U also for coverage extension in locations without licensed band coverage as well as to roll out, for example, in-building networks provided by the building owner. 5G-U supports wideband operation, with bandwidths exceeding 100 MHz (in inte- gral multiples of 20 MHz). The coexistence with LTE-based systems and Wi-Fi will be ensured with energy detection, and possibly other methods to be considered as well, especially for cases when there is no system used on the same channel other than 5G-U. The 3GPP studies as presented in [2] show that fair coexistence can be ensured with Wi-Fi as well as with LTE-based LAA, both of which have been deployed already in the 5 GHz band. Further discussions will be held regarding extending the unlicensed band operation to above 6 GHz as well. Figure 15.3 shows an example of coexistence results between Wi-Fi and 5G-U [3]. In the case of two 5G-U networks, the throughput is much better than when there are two Wi-Fi networks. Moreover, replacing one of the Wi-Fi networks with 5G-U results in a higher throughput for the remaining Wi-Fi network; that is, 5G-U is a better neighbor for Wi-Fi than another Wi-Fi network. The same effect was already observed with LTE LAA, since the spectral efficiency of the 3GPP-based systems exceed Wi-Fi by far, and both LTE LAA and 5G-U were originally designed to be more tolerant toward interference than Wi-Fi. In the example case, 5G-U, the mean throughput is up to five times better than that of Wi-Fi in the presence of interference. This allows one to get much better performance using 5G-U from the available 