Adaptive frequency-domain interference coordination combined with CRE in heterogeneous network

Cell Range Expansion (CRE) technology provide an opportunity for more users to transfer from macro cell to small cell in the Long Term Evolution Advanced (LTE-A) heterogeneous networks. However, these CRE users located at the edge of small cells will be seriously interfered by macro cell, resulting in a sharp decline to their Signal to Interference plus Noise Ratio (SINR). In order to reduce this interference, a method of frequency domain self-organizing interference coordination technique combined with CRE technology is proposed in our paper. In this method, the total spectrum bandwidth is divided into two parts according to the frequency partition ratio which can be adaptively controlled. One part of the bandwidth in which the transmission power of macro cell is reduced. Another band with the transmission power of macro cell do not change. Based on this method, small cell users with low SINR including CRE users and macro cell users with high SINR scheduled in the power reduced band. Our simulation results show that the proposed scheme in this paper can effectively improve the system´s throughput and increase the small cell´s edge users´ performance.