System-level performance evaluation of ultra-dense networks for 5G

Ultra dense network (UDN) is a promising technology enabling high power and spectrum efficiencies for future wireless systems such as 5th generation (5G) wireless networks. Regarding the importance of UDN, in this paper we investigate the performance of small cell networks with different small cell base station (SBS) densities via using a system-level simulation platform and some real traffic data provided by China Mobile Research Institute. We first build a practical distribution model for SBSs and then construct practical small cell deployment scenarios considering many practical limitations. After that, network throughputs with different transmission powers and densities of SBSs are simulated. In addition, the performance of cell edge users is also evaluated. Numerical results demonstrate that PPP model still provides an accurate model for constructing unplanned tiers even when many practical limitations are taken into account.