Cooperative small cell networks: high capacity for hotspots with interference mitigation

Due to the high potential to enhance spectral efficiency and spatial reuse, small cell networks, SCNs, have emerged as a promising solution to improve the capacity of mobile communication systems so as to satisfy the ever growing demand for high data rate services. However, without proper planning, the dense deployment of SCNs may cause severe interference, resulting in limited capacity. In hotspots with a large number of users, the small cell network is challenged by the extremely high aggregated capacity requirement and may fail to guarantee the quality of service of all users. To leverage the benefits of SCNs and overcome the drawbacks, we propose a cooperative small cell network, CSCN, architecture that jointly utilizes several advanced techniques to enhance the capacity of hotspots. In this article, we first examine the existing solutions for capacity enhancement and hotspots. We then present the basic concept of the proposed CSCN architecture, and discuss the related technical aspects. The high potential of a CSCN in terms of capacity improvement and interference mitigation is demonstrated by a simulation study. Finally, we present several open problems for future research based on the CSCN architecture.