Rate and coverage analysis in multi-tier heterogeneous network using stochastic geometry approach

Abstract

To meet massive wireless traffic demand in the upcoming fifth generation cellular networks, the rapid growth of small cells is emerging as an attractive solution and deriving cellular network toward randomness and heterogeneity. In a typical macrocell, there are many deployed femtocells and few picocells with unplanned users. In such a heterogeneous cellular network, using random spatial models is a rational approach to characterize the base stations (BS) locations. The key issue for the deployment of small cells is interference management. Considering multi-tier cellular network, in this paper we develop a general kth-tier BSs model that captures the downlink multi-antenna heterogeneous cellular network with variable parameters such as the number of antenna, target signal-to-noise-and-interference ratio (SINR), transmitted power, and deployment density. In particular, we consider K−tier transmission and compare it with a single-tier, traditional grid model and multi-antenna ultra-dense network (UDN) model to obtain tractable rate and coverage probability. The results showed that the proposed model outperforms the traditional multi-antenna ultra-dense network (UDN) model and its accuracy is confirmed to be similar to the traditional grid model. In addition, a comparison with the counterpart uplink model is provided, which reveals that the coverage probability of the proposed downlink model decreases when the fractional power control (ϵ) increases in the uplink.