assume that the site density can be increased from 30 to 50/km2 and the spectral efficiency can be increased by a factor of 3 compared to LTE-Advanced. We also assume that the traffic distribution becomes less equal with a higher site density. The result is a capacity up to 13 Gbps. If the site density needs to be increased further, the cell range decreases to 50-100 m, and it makes sense to utilize mmWave. We assume 800 MHz of spectrum and 150 sites/km² with 24-39 GHz. This deployment gives more than 100 Gbps/km. Spectrum above 50 GHz gives access to even more spectrum and higher site density. We assume 3000 MHz and 300/km2 corresponding to a cell range below 50 m. This deployment case gives approximately 1 Tbps/km2 (Figure 10.66). In addition to the high traffic density, 5G must also support high device density. The 5G target is to support 1 million devices per km². The high device density is needed for the massive number of IoT objects. There are no theoretical limits for the device density if the data volumes are low. We present here the required signaling capacity to support a large number of devices. The signaling (setup) capacity and the connectivity are likely the first bottlenecks in the LTE system. We assume 50 base stations per km2 and a traf- fic distribution factor of 4.0 (see Table 10.23). The resulting signaling capacity depends on the frequency of the transmission. We consider here transmission frequencies from once per 10 S to once per hour. The results are shown in Figure 10.67. The required sig- naling capacity per base station is up to 000/s in the extreme case with a transmission frequency of once per 10 S. The corresponding signaling is 2000 setups per second per base station with once per minute and 33 setups per second per base station with once per hour activity. For reference, the existing LTE solutions can support more than 1000 setups per second per base station, which already allows a very high IoT density. Table 10.23 Assumptions for the device density. Number of devices 1 million Si