A Novel Spectrum Partitioning Scheme for Dynamic Heterogeneous Networks

Dynamic heterogeneous networks (HetNets) in which small cells operate in dynamic time division duplex (D-TDD) systems enable the instantaneous traffic load to be handled with greater spectral efficiency than conventional HetNets. However, combining HetNets and D-TDD systems causes cross-link interference (CLI) both within the same tier and across tiers, negatively impacting system performance. In this paper, we point out that small cells are underprivileged in terms of interference mitigation under the conventional spectrum partitioning usage. Accordingly, we propose employing a novel spectrum partitioning scheme that brings up interference scenarios where we can take advantage of multiple-input multiple-output (MIMO) compatibility from macro base stations. Simulation results show that the proposed spectrum usage in combination with general MIMO schemes achieves significant performance enhancement in terms of small cell capacity at the cost of a relatively small degradation in macro cell capacity.