Interference alignment for MIMO downlink femtocell networks

Interference management in femtocell network is an important issue to achieve the network throughput gain as well as not degrading the throughput of the macrocell tier. In this paper we consider a MIMO femtocell network and propose an interference mitigation strategy using interference alignment (IA) to mitigate the interference at the macrocell users (MUEs) caused by femtocell base stations (FBSs). Since the resource of the macrocell tier is scarcer than the femtocell tier, the transceiver design algorithm is proposed to guarantee the performance of the macrocell tier. Numerical simulations are given and the results show that by introducing IA algorithm the proposed algorithm achieve better femtocell tier throughput performance especially with dense femtocell deployment, with only a small degradation in macrocell tier throughput.