Modeling and Analysis of Downlink Heterogeneous Cellular Networks

Abstract

Owing to the irregular deployment of different types of base stations (BSs), cellular networks are now becoming more and more complex. In this study, a tractable and accurate framework based on hybrid model is proposed for heterogeneous cellular networks (HCNs). According to the distribution characteristics of different types of BSs in HCNs, the plane distributed macro BSs are termed as tier-1 cells, whereas the small cells, which are spatial distributed, are modeled as tier-2. First, we derive the probability of a target user communicate with macro BS or small cell. Second, we calculate the coverage probability that the target user communicate with macro or small cell respectively. Finally, we obtain the general closed expressions of whole coverage probability. In some special cases, the expressions present simple closed forms and can be calculated easily. Compared with the presented model, the simulation results show that our model is accurate within 1-2dB.