Ultra-Dense Heterogeneous Networks with Full-Duplex Small Cell Base Stations

The FD communication technique has been recently proposed as a new paradigm to increase the spectral efficiency of wireless systems. In this article, we investigate the application of FD communications to ultra-dense heterogeneous networks where small base stations can work in the FD mode. In such networks, it is a challenging task to coordinate various kinds of interference caused by FD communications, including self-interference, intra-cell and inter-cell uplink-to-downlink interference. To deal with it, we have developed a novel ICIC scheme, which consists of four steps: base station association, user pairing and mode selection, power control, and resource block allocation. The implementation issue of the proposed scheme is also discussed. Simulation results demonstrate that our proposed ICIC scheme can effectively harvest the FD gain for ultra-dense heterogeneous networks. Finally, several important future directions and open challenges are identified in this article.