Fuzzy logic-based virtual cell design in ultra-dense networks

Abstract

One of the main trends in the fifth generation (5G) cellular network is the bifurcation of systems that enable network densification. With this trend, ultra-dense networks (UDN) become a pillar technology to provide high data rates gains. However, these gains come at the expense of more complex interference and higher handover frequency. The user-centric virtual cell conception has been proposed to solve these problems. But it still has encountered some challenges in practical application. In this paper, we propose a fuzzy logic-based virtual cell design to balance data rates and resource overhead in order to improve virtual cell applicability. In our design, we consider a practical UDN scenario with imperfect channel state information (CSI) feedback and model it by stochastic geometry theory. Then, we find the optimal radius of virtual cells by maximizing the system spectral efficiency. On the basis, we propose a fuzzy logic-based activation strategy selection (FASS) algorithm to rationally choose the virtual cell activation threshold and resources allocation scheme under different traffic loads and quality of service (QoS) requirement. Simulation results demonstrate that the proposed solution can effectively eliminate the interference, obviously improve the user’s system spectral efficiency and dynamically adapt to different traffic loads.