Cell Association Combined with Interference Management in Heterogeneous Cellular Networks Using a Distributed Algorithm

Due to the growing demand of cellular networks, the need to increase the capacity of these networks has always been a challenge. Heterogeneous cellular networks using small base stations alongside macro base stations are low cost and effective solutions for this problem. However the differences between the various BSs in heterogeneous networks have created new challenges in terms of cell association and interference management compared with the traditional cellular networks. Therefore, the design of new and efficient methods for allocating cells and resources in these networks is an open research topic. This paper addresses the need for an efficient solution to simultaneously allocating cells and subbands in order to prevent interference for all users. The protocol interference model and its modeling methods in cellular networks have been studied. After modeling the system, the problem is formulated as an integer optimization problem. Then, by reformulating the problem and using a one-level dual decomposition, an algorithm with efficient complexity with near-optimal answers is attained. Thereafter, a distributed protocol is presented in which each user and each base station would only require local information for making decisions. The simulation results confirm the effectiveness of the proposed solution.