Cell capacity for 5G cellular network with inter-beam interference

The emerging 5G cellular networks will operate at millimeter wave (mmWave) frequency bands to enhance the cell capacity. Massive MIMO antenna array and beamforming technology are used in order to overcome propagation limitations of mmWave band. Multi-beam based communication system is considered as the basic structure for 5G mobile network. However, to optimize the cell capacity, the question of how many beams are required remains unclear. In this paper, considering 5G mmWave cellular system with massive MIMO and beamforming technologies, we accurately model the inter-beam interference and evaluate the cell capacity and outage probability of the system. The simulation results give the optimal number of beams to maximize the cell capacity. Our research provides a possible guidance for the design of 5G cellular system.