o resources). To have higher capacity, 5G mobile networks require more bits/s/Hz, which can be provided (as one approach) with better modulation and coding schemes. Another approach to increase bit/s/Hz is using multiple antennas on the sender's or receiver's side, i.e. multiple input multiple output (MIMO), which adds more capacity on the same frequency band in use between the base station and the mobile users. For example, if the bitrate in the mobile network with single antennas on both ends (mobile terminal and base station) is B bit/s, then MIMO (where n is an integer) will result in N X B bitrate. For example, if B = 10 Mbit/s with SISO (single input antenna and single output antenna), then 1024 X 1024 MIMO will provide 1024 X 10 Mbit/s = 10 Gbit/s. Of course, to have the advantage of MIMO use, the same MIMO should be supported on both ends, the mobile terminal and the base station. Hence, the 5G mobile network tar- gets constant improvement in MIMO (from one release to the next), developing toward massive MIMO with the aim of maximizing the bits/s/Hz. However, to increase capacity as needed or expected in 5G requires additional spec- trum. But the "good" spectrum for macro mobile coverage is below 6 GHz, and it is becoming more crowded with each mobile generation. Therefore, 5G also enters the spectrum above 6 GHz (e.g. different bands between 24.25 and 86 GHz, etc.) which can be used on smaller areas in hotspot locations, besides allocating new bands below 6 GHz to 5G (e.g. 600 MHz band, 1.5 GHz band, 3.5 GHz band, 5-6 GHz band). Whatever the spectrum in use in a mobile network, there is always a demand for more capacity (e.g. 5 QoS for Mobile Ultra-Broadband in hotspot locations in cities). To provide capacity requires reusing the spectrum on smaller distances (because the spectrum that can be used is limited in a given location), which results in scenarios with many small cells deployments for 5G mobile networks. Also, the small cells by default improve the QoS because they are smaller, SO the users at 