Interference coordination in HetNet: Can D2D communications help?

In this paper, the problem of interference coordination in heterogeneous networks, comprising macro base stations (MBS) and several underlay small cells (SCS) is analyzed. Such problem is normally solved by coordinating and orthogonalizing the transmissions of the MBS and the SCS in order to reduce the global interference level, at the price of underutilized network resources. To solve this problem, an interference coordination scheme, based on the exploitation of device-to-device (D2D) enabled relaying, and allowing full spectrum usage is presented. This scheme is based on the idea of substituting long-range transmission with short-range D2D communications, which are characterized by low power transmissions, thus introducing low interference to the overall system. The proposed algorithm is compared to standard enhanced inter cell interference coordination (eICIC) scheme and its performance gain is assessed through numerical simulations.