Device-to-Device Communication Underlaying MU-MIMO in Multi-Cell Networks with Interference Alignment

Interference is a key problem for multi-cell networks and interference alignment (IA) is a promising method to manage interference. This paper investigates whether a feasible IA scheme can improve the system performance of Device-to-Device(D2D) communication underlaying multiple-input-multiple-output (MU-MIMO) uplink in multi-cell networks. We propose a novel cell division pattern based on conventional fractional frequency reuse (FFR) to create user clusters to eliminate interference. For the intra-cell IA-cluster and inter-cell IA-cluster, we present the feasibility of IA, a feasible configuration and give the corresponding precoding, decoding matrices. The simulation results show that IA acquiring user clustering gains outperform the multiplex scheme and orthogonal scheme. Additionally, the optimal frequency reuse partitioning radius is found to obtain the highest spectrum efficiency. Index Terms-D2D communication, Multi-cell networks, Interference alignment, MU-MIMO, Clusters.