A backhaul-aware cell selection algorithm for heterogeneous cellular networks

This paper considers heterogeneous cellular networks, where cluster of small cells are deployed to create local hot spots inside the macro cell. In the past, most of the research in this topic has focused on mitigating inter cell interference; however, wireless backhaul has recently emerged as an urgent challenge to enable ubiquitous broadband wireless services at small cells. Hence, we propose a novel cell selection framework, which associates users and heterogeneous access nodes to improve the efficiency in the overall radio and backhaul resource utilization and avoid load congestions. We also model the relationships amongst cell load, resource management, backhaul capacity constraints, and the overall network capacity. Then, we describe the cell selection problem and we present a heuristic algorithm, named as Evolve, to solve it with limited complexity. Our analysis shows that Evolve achieves near optimal performance leading to notable capacity improvements with respect to the classic SINR based association scheme.