Coordinated downlink multi-point communications in heterogeneous cellular networks

Abstract—In this paper we assess how coordination among base stations can be exploited to improve downlink capacity in fourth generation (4G) cellular networks. We focus on heteroge-neous networks where low-power pico cells are deployed within the coverage area of an existing macro network with the aim of offloading traffic from the (potentially congested) macro cells to low-power cells. Firstly, we describe an enhanced inter-cell interference coordination scheme which is shown to achieve a significant capacity gain in such deployments by leveraging a loose coordination among neighbor base stations. Secondly, we explore how a tighter coordination among base stations can be exploited to further improve the network capacity. Even though the schemes described in this paper apply to long term evolution (LTE) wireless networks, we point out that most of the findings and conclusions we draw apply to any cellular network. I