Analysis of spectral and energy efficiency in ultra-dense network

To meet the challenge of the ever-growing traffic volume in current wireless communications, ultra-dense network (UDN) deployment with high system capacity has attracted wide attention in recent years. However, existing researches on UDN mainly focus on system throughput while ignore energy efficiency (EE). Therefore, we will analyze the UDN performance including not only system throughput but also EE in this paper. We first theoretically analyze the performance of UDN in terms of cell average spectral efficiency, area throughput, and network energy efficiency using the tools from stochastic geometry. Then, we demonstrate the effects of the frequency reuse factor on these performance metrics, and conclude that when taking the overall performance into consideration, the network performance can not be optimal simultaneously under the same parameters. Some tradeoffs need to be considered to achieve a better network performance. Finally, we validate the analysis through simulations.