Nowadays new key parameters have to be satisfied in the world of telecommunications, in terms of speed, latency and number of users to serve. In order to satisfy these new parameters it is necessary to move from the 4G technology to the 5G technology. It implements many techniques that are aimed to reach the goals described above, and in particular we are interested in the description of network densification and small cells. As the number of users increases, it is necessary to increase also the number of base stations covering the geographical area, in such a way there are many small cells where the bit rates are reasonably high.