Interference management in backhaul constrained 5G HetNets through coordinated multipoint

Abstract

The inter-cell interference (ICI) is a major bottleneck that harshly impairs the cell-edge performance in the cellular networks. In heterogeneous networks (HetNets), time domain enhanced inter-cell interference coordination (TD-eICIC) is a promising and well recognized cell-coordination technique to cope with the inter-tier cell interference. However, this scheme incurs significant loss in the allocated spectrum resources caused by blanked or reduced power subframes. The coordinated multipoint (CoMP) is a spectrally efficient and dynamic coordination approach to improve the performance of cell-edge users. In this article, first we provide a brief overview of conventional interference mitigation techniques in the heterogeneous networks. Next, application of CoMP on top of conventional TD-eICIC is investigated to diminish the pitfalls of TD-eICIC. Primarily, we propose a simplified but efficient multi-tier adaptive cell-coordination approach by combining features of joint transmission CoMP (JT-CoMP) and TD-eICIC to provide a pragmatic solution in the dynamically varying mobile environments. Finally, a hypothetical HetNet-CoMP paradigm is propounded that can effectually alleviate the interference in the backhaul-constrained densed fifth generation (5G) and beyond networks where multiple HetNet co-exist in the neighborhood. The analytical expressions and evaluation results validate the improvements achieved by the proposed methods in the network performance in terms of cell-edge user throughput and spectral efficiency performance metrics.